Toyota Prius: Lighting System

Toyota Prius (XW60) 2023-2025 Service Manual / Vehicle Exterior / Lighting (ext) / Lighting System

Precaution
Parts Location
System Diagram
How To Proceed With Troubleshooting
Operation Check
Customize Parameters
Problem Symptoms Table
Terminals Of Ecu
Data List / Active Test
Diagnostic Trouble Code Chart
Light Sensor Circuit Malfunction (B124400)
Headlight LH Circuit (B243900,B243A00)
Lost Communication With ECM/PCM "A" Missing Message (U010087,...,U111787)
Turn Signal Switch Circuit
Headlight Dimmer Switch Circuit
Parking Light/Daytime Running Light Circuit
Hazard Warning Switch Circuit
Back-up Light Circuit
Charge Lid Illumination Malfunction
LO-beam Headlight does not Illuminate
Taillight Relay Circuit
High Beam Headlight Circuit

Precaution

PRECAUTION

PRECAUTIONS FOR DISCONNECTING CABLE FROM NEGATIVE (-) AUXILIARY BATTERY TERMINAL

NOTICE:

After the ignition switch is turned off, there may be a waiting time before disconnecting the negative (-) auxiliary battery terminal.

Click here

HINT:

When disconnecting and reconnecting the auxiliary battery, there is an automatic learning function that completes learning when the respective system is used.

Click here

PRECAUTIONS FOR REMOVAL, INSTALLATION AND REPLACEMENT OF COMPONENTS

(a) After replacing certain components, it may be necessary to update the ECU security key.

Click here

Parts Location

PARTS LOCATION

ILLUSTRATION

*A	w/ Accessory Light	*B	w/ Side Turn Signal Light
*C	w/ Front Side Marker Light	-	-
*1	HEADLIGHT ASSEMBLY LH - HEADLIGHT HOUSING SUB-ASSEMBLY LH - HEADLIGHT HOUSING LH (w/o Front Side Marker Light) - HEADLIGHT UNIT ASSEMBLY LH (w/o Front Side Marker Light) - LIGHT CONTROL LED ECU LH (w/o Front Side Marker Light) - HEADLIGHT LEVELING MOTOR (w/o Front Side Marker Light) - HEADLIGHT FRONT TURN SIGNAL LED (w/o Front Turn Signal LED Socket)	*2	HEADLIGHT ASSEMBLY RH - HEADLIGHT HOUSING SUB-ASSEMBLY RH - HEADLIGHT HOUSING RH (w/o Front Side Marker Light) - HEADLIGHT UNIT ASSEMBLY RH (w/o Front Side Marker Light) - LIGHT CONTROL LED ECU RH (w/o Front Side Marker Light) - HEADLIGHT LEVELING MOTOR (w/o Front Side Marker Light) - HEADLIGHT FRONT TURN SIGNAL LED (w/o Front Turn Signal LED Socket)
*3	LED ILLUMINATION LIGHT LH	*4	LED ILLUMINATION LIGHT RH
*5	SIDE TURN SIGNAL LIGHT ASSEMBLY LH	*6	SIDE TURN SIGNAL LIGHT ASSEMBLY RH
*7	NO. 1 ENGINE ROOM RELAY BLOCK AND NO. 1 JUNCTION BLOCK ASSEMBLY - INP STD NO. 1 FUSE	*8	FRONT MARKER LIGHT ASSEMBLY LH
*9	FRONT MARKER LIGHT ASSEMBLY RH	*10	MILLIMETER WAVE RADAR SENSOR ASSEMBLY
*11	NO. 2 SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY)	*12	FORWARD RECOGNITION CAMERA

ILLUSTRATION

*A	w/ Rear Side Marker Light	*B	w/ Tail Light LED
*C	for PHEV Model	-	-
*1	REAR COMBINATION LIGHT ASSEMBLY LH - REAR COMBINATION LIGHT LENS AND BODY LH - REAR TURN SIGNAL LIGHT LED LH	*2	REAR COMBINATION LIGHT ASSEMBLY RH - REAR COMBINATION LIGHT LENS AND BODY RH - REAR TURN SIGNAL LIGHT LED RH
*3	REAR LIGHT ASSEMBLY - TAIL LIGHT LED (LH) - TAIL LIGHT LED (RH)	*4	CENTER STOP LIGHT ASSEMBLY - CENTER STOP LIGHT CORD ASSEMBLY
*5	LICENSE PLATE LIGHT ASSEMBLY (LH)	*6	LICENSE PLATE LIGHT ASSEMBLY (RH)
*7	BACK-UP LIGHT ASSEMBLY LH - BACK-UP LIGHT LED LH	*8	BACK-UP LIGHT ASSEMBLY RH - BACK-UP LIGHT LED RH
*9	REAR SIDE MARKER LIGHT ASSEMBLY LH	*10	REAR SIDE MARKER LIGHT ASSEMBLY RH
*11	PLUGIN CHARGE CONTROL ECU ASSEMBLY	*12	CHARGE LID WITH MOTOR LOCK ASSEMBLY
*13	SPOT LIGHT ASSEMBLY	-	-

ILLUSTRATION

*A	w/ Automatic Light Control	*B	w/ Manual Leveling System
*1	AUTOMATIC LIGHT CONTROL SENSOR	*2	STEERING WHEEL SWITCH HOUSING
*3	HYBRID Toyota Prius Vehicle CONTROL ECU	*4	TURN SIGNAL SWITCH
*5	HAZARD WARNING SIGNAL SWITCH ASSEMBLY	*6	COMBINATION METER ASSEMBLY
*7	STEERING SENSOR	*8	DLC3
*9	STOP LIGHT SWITCH ASSEMBLY	*10	AIRBAG ECU ASSEMBLY
*11	MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)	*12	POWER DISTRIBUTION BOX ASSEMBLY - ECU-IGR NO. 1 FUSE - ECU-B NO. 2 FUSE - TAIL FUSE - TAIL RELAY - ECU-B NO. 3 FUSE (for PHEV Model)
*13	SHIFT CONTROL ECU (TRANSMISSION FLOOR SHIFT ASSEMBLY)	*14	HEADLIGHT LEVELING SWITCH

System Diagram

SYSTEM DIAGRAM

How To Proceed With Troubleshooting

CAUTION / NOTICE / HINT

HINT:

Use the following procedure to troubleshoot the lighting system.
*: Use the GTS.

PROCEDURE

1.	Toyota Prius Vehicle BROUGHT TO WORKSHOP

2.	CUSTOMER PROBLEM ANALYSIS

HINT:

In troubleshooting, confirm that the problem symptoms have been accurately identified. Preconceptions should be discarded in order to make an accurate judgment. To clearly understand what the problem symptoms are, it is extremely important to ask the customer about the problem and the conditions at the time the malfunction occurred.
Gather as much information as possible for reference. Past problems that seem unrelated may also help in some cases.

The following 5 items are important points for problem analysis:

What	Toyota Prius Vehicle model, system name
When	Date, time, occurrence frequency
Where	Road conditions
Under what conditions?	Driving conditions, weather conditions
How did it happen?	Problem symptoms

PRE-CHECK

(a) Measure the auxiliary battery voltage with the ignition switch off.

Standard Voltage:

11 to 14 V

If the voltage is below 11 V, recharge or replace the auxiliary battery before proceeding to the next step.

(b) Check the fuses and relays.

(c) Check the connector connections and terminals to make sure that there are no abnormalities such as loose connections, deformation, etc.

4.	CHECK COMMUNICATION FUNCTION OF CAN COMMUNICATION SYSTEM*

(a) Using the GTS, check for CAN communication system DTCs.

for HEV Model: Click here

for PHEV Model: Click here

Result	Proceed to
CAN DTCs are not output	A
CAN DTCs are output	B

GO TO CAN COMMUNICATION SYSTEM

for HEV Model: Click here

for PHEV Model: Click here

5.	CHECK COMMUNICATION FUNCTION OF CXPI COMMUNICATION SYSTEM*

(a) Using the GTS, check for CXPI communication system DTCs.

Click here

Result	Proceed to
CAN DTCs are not output	A
CAN DTCs are output	B

GO TO CXPI COMMUNICATION SYSTEM

6.	CHECK FOR DTC*

(a) Check for DTCs.

Body Electrical > Main Body > Trouble Codes

Result	Proceed to
DTCs are not output	A
DTCs are output	B

GO TO DIAGNOSTIC TROUBLE CODE CHART

7.	PROBLEM SYMPTOMS TABLE

(a) Refer to Problem Symptoms Table.

Click here

Result	Proceed to
Fault is not listed in Problem Symptoms Table	A
Fault is listed in Problem Symptoms Table	B

GO TO PROBLEM SYMPTOMS TABLE

8.	OVERALL ANALYSIS AND TROUBLESHOOTING*

(a) Operation Check.

Click here

(b) Terminals of ECU.

Click here

(d) On-Toyota Prius vehicle Inspection.

(e) Inspection.

9.	ADJUST, REPAIR OR REPLACE

10.	CONFIRMATION TEST

END

Operation Check

OPERATION CHECK

AUTOMATIC LIGHT CONTROL SYSTEM OPERATION CHECK (w/ Automatic Light Control)

NOTICE:

Make sure that the customize settings are set to default when performing the automatic light control system operation check.

Click here

(a) Turn the ignition switch to ON.

(b) Turn the light control switch to the AUTO position.

(d) Check that the taillights and low beam headlights come on.

(e) Uncover the automatic light control sensor.

(f) Check that the low beam headlights and taillights turn off.

LIGHT AUTO TURN-OFF SYSTEM OPERATION CHECK (for Driver Door-linked Auto Light Turn-off System)

(a) Close all of the doors.

(b) Turn the ignition switch to ON.

(d) Turn the ignition switch off.

(e) Open the driver door.

(f) Check that all of the lights turn off immediately.

LIGHT AUTO TURN-OFF SYSTEM OPERATION CHECK (w/ Delay Function)

NOTICE:

Make sure that the customize settings are set to default when performing the light auto turn-off system operation check.

Click here

(a) When the taillights are on (low beam headlights are not on)

(1) Close all of the doors.

(2) Turn the ignition switch to ON.

(3) Turn the taillights on.

(4) Turn the ignition switch off.

(5) Open the driver door.

(6) Check that all of the lights turn off immediately.

(b) When the low beam headlights are on

(1) Close all of the doors.

(2) Turn the ignition switch to ON.

(3) Turn the low beam headlights on.

(4) Turn the ignition switch off.

(5) Open any of the doors.

(6) Close the door.

(7) Check that all of the lights turn off after 30 seconds (delay function).

HINT:

Before the lights turn off, if the lock button on the key is pushed after all of the doors are locked, all of the lights will turn off immediately.

DAYTIME RUNNING LIGHT SYSTEM OPERATION CHECK (w/ Daytime Running Light)

NOTICE:

Make sure that the customize settings are set to default when performing the daytime running light system operation check.*

Click here

*: for Toyota Prius vehicles with customize setting "DRL Function"

(a) Turn the ignition switch to ON (READY).

(b) Turn the light control switch to the tail or AUTO position (with the low beam headlights not turned on via the automatic light control system).

(d) Check that the daytime running lights come on.

NOTICE:

Make sure that the customize settings are set to default when performing the wiper-linked low beam headlight control system operation check.

Click here

WIPER-LINKED LOW BEAM HEADLIGHT CONTROL SYSTEM OPERATION CHECK (w/ Wiper-linked Low Beam Headlight Control System)

(a) Turn the ignition switch to ON.

(b) Shine a light on the automatic light control sensor.

HINT:

If troubleshooting is being performed in a bright area, such as outside on a sunny day, it will not be necessary to perform this step.

(d) Operate the front wipers for 10 seconds or more (except MIST or washer-linked wiper operation) and check that the low beam headlights*1 or high beam headlights*2 illuminate.

*1: Dimmer switch not high position
*2: Dimmer switch high position

MANUAL HEADLIGHT BEAM LEVEL CONTROL SYSTEM OPERATION CHECK (w/ Manual Leveling System)

(a) Turn the ignition switch to ON (IG).

(b) Turn the headlights on.

(d) Check that the headlight beam level changes when the headlight leveling switch is operated.

Customize Parameters

CUSTOMIZE PARAMETERS

CUSTOMIZE LIGHTING SYSTEM (EXT)

NOTICE:

When the customer requests a change in a function, first make sure that the function can be customized.
Be sure to make a note of the current settings before customizing.
When troubleshooting a function, first make sure that the function is set to the default setting.

HINT:

The following items can be customized.

(a) Customizing with the GTS

(1) Enter the following menus: Customize Setting / Light Control, Warning or Illuminated Entry.

(2) Select the setting by referring to the table below.

Light Control

Tester Display	Description	Default	Setting	ECU
Tail Remind Buzzer Function	Sounds a buzzer when the driver door is opened with the light control switch in the tail or head position.	Enable	$00:Disable,$01:Enable	Main Body ECU (Multiplex Network Body ECU)
Headlight ON in Conjunction with Wiper Function	Turns the low beam headlights on/off according to wiper operation.*1	Enable	$00:Disable,$01:Enable	Main Body ECU (Multiplex Network Body ECU)
Brightness Level Adjust (Lowering)	Changes the ambient brightness level required to dim the lights such as the indicator lights of the combination meter, A/C indicator light and clock.*A	Normal	$00:Normal,$01:Dark2,$02:Dark1,$03:Light1,$04:Light2	Main Body ECU (Multiplex Network Body ECU)
Brightness Level Adjust (Canceling)	Changes the ambient brightness level required to cancel the dimming of the lights such as the indicator lights of the combination meter, A/C indicator light and clock.*B	Normal	$00:Normal,$01:Dark2,$02:Dark1,$03:Light1,$04:Light2	Main Body ECU (Multiplex Network Body ECU)
Sensitivity Adjust	Adjusts the sensitivity of the automatic light control system.*C	Normal	$01:Dark2,$02:Dark1,$00:Normal,$03:Light1,$04:Light2	Main Body ECU (Multiplex Network Body ECU)
Light Auto OFF Delay Setting	Keeps the headlights on for a certain period of time after turning the ignition switch off and closing all of doors with the low beam headlights on.*2	30 s	$00:OFF,$01:30sec,$02:60sec,$03:90sec	Main Body ECU (Multiplex Network Body ECU)
DRL Function	Turns the DRL function on/off.*3	Enable	$00:Disable,$01:Enable	Main Body ECU (Multiplex Network Body ECU)

*1: w/ Wiper-linked Low Beam Headlight Control System
*2: w/ Delay Function
*3: for Toyota Prius vehicles with customize setting "DRL Function"

HINT:

The sensitivity adjustment may be difficult to confirm. Check by driving the vehicle.

Warning

Tester Display	Description	Default	Setting	ECU
Lane Change Flashing Times Adjust	Function to change the lane change flashing times.	3	$00:OFF,$01:3,$02:4,$03:5,$04:6,$05:7	Combination Meter Assembly

(b) Customizing with the multi-display

(1) Enter the following menus:

Settings (icon) / Toyota Prius Vehicle customize

HINT:

Depending on the specifications of the vehicle, some items may not be displayed.

(2) Select the setting by referring to the table below.

Display	Default	Content	Setting	Relevant ECU
Headlights Auto-on Sensitivity	Normal	Adjusts the sensitivity of the automatic light control system.*A	Normal, Dark2, Dark1, Light1 or Light2	Main Body ECU (Multiplex Network Body ECU)
Headlights Auto-off Timer*1	30 sec.	Keeps the headlights on for a certain period of time after turning the ignition switch off and closing all of doors with the low beam headlights on.	Off, 30 sec., 60 sec. or 90 sec.	Main Body ECU (Multiplex Network Body ECU)
Daytime Running Lights*2	On	Turns the DRL function on/off.	On or Off	Main Body ECU (Multiplex Network Body ECU)

*1: w/ Delay Function
*2: for Toyota Prius vehicles with customize setting "Daytime Running Lights"

HINT:

The sensitivity adjustment may be difficult to confirm. Check by driving the vehicle.

Problem Symptoms Table

PROBLEM SYMPTOMS TABLE

NOTICE:

Before replacing the main body ECU (multiplex network body ECU), refer to Registration.
Click here
When replacing the combination meter assembly, always replace it with a new one. If a combination meter assembly which was installed to another Toyota Prius vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.
When replacing the combination meter assembly, update the ECU security key.
Click here

HINT:

Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.

Headlight

Symptom	Suspected Area	Link
Left or right low beam headlight does not illuminate	Refer to "LO-beam Headlight does not Illuminate"
Both left and right low beam headlights do not illuminate	Headlight dimmer switch circuit
Both left and right low beam headlights do not illuminate	Main body ECU (Multiplex network body ECU)
Left or right high beam headlight does not illuminate	High beam headlight circuit
Both left and right high beam headlights do not illuminate	Headlight dimmer switch circuit
Both left and right high beam headlights do not illuminate	Main body ECU (Multiplex network body ECU)
High Flash (passing function) does not operate (high beam headlights are normal)	Headlight dimmer switch circuit
	Main body ECU (Multiplex network body ECU)

Parking Light, Accessory Light*1, Daytime Running Light*2

Symptom	Suspected Area	Link
Left or right parking light, accessory light or daytime running light do not illuminate	Parking light/daytime running light circuit
Both left and right parking lights, accessory light or daytime running light do not illuminate	Check customize settings*3
	Headlight dimmer switch circuit
	Main body ECU (Multiplex network body ECU)

*1: w/ Accessory Light
*2: w/ Daytime Running Light
*3: for Toyota Prius vehicles with customize setting "DRL Function"

Front Side Marker Light (w/ Front Side Marker Light)

Symptom	Suspected Area	Link
Left or right front side marker light does not illuminate	Front marker light assembly
Left or right front side marker light does not illuminate	Harness or connector	-

Accessory Light (w/ Accessory Light)

Symptom	Suspected Area	Link
Left or right accessory light does not illuminate	LED illumination light
Left or right accessory light does not illuminate	Harness or connector	-
Both left and right accessory lights do not illuminate	Taillight relay circuit
Both left and right accessory lights do not illuminate	Harness or connector	-

Taillight

Symptom	Suspected Area	Link
Left or right taillight (rear combination light assembly) does not illuminate	Rear combination light lens and body
	Harness or connector	-
Left or right taillight (rear light assembly) does not illuminate*	Tail light LED
	Harness or connector	-
All of the taillights, license plate lights and rear side marker lights do not illuminate	Headlight dimmer switch circuit
	Taillight relay circuit
	Main body ECU (Multiplex network body ECU)

*: w/ Tail Light LED

Rear Side Marker Light (w/ Rear Side Marker Light)

Symptom	Suspected Area	Link
Left or right rear side marker light does not illuminate	Rear side marker light assembly
Left or right rear side marker light does not illuminate	Harness or connector	-

License Plate Light

Symptom	Suspected Area	Link
License plate light does not illuminate	License plate light assembly
License plate light does not illuminate	Harness or connector	-

Stop Light

Symptom	Suspected Area	Link
Left or right stop light (rear combination light assembly) does not illuminate	Rear combination light lens and body
	Harness or connector	-
All of the stop lights do not illuminate	STOP fuse	-
	Stop light switch assembly
	Harness or connector	-

High Mounted Stop Light

Symptom	Suspected Area	Link
High mounted stop light does not illuminate	Center stop light assembly
	Center stop light cord assembly
	Harness or connector	-

Back-up Light

Symptom	Suspected Area	Link
Left or right back-up light does not illuminate	Back-up light LED
Left or right back-up light does not illuminate	Harness or connector	-
Both left and right back-up lights do not illuminate	Back-up light circuit

Turn Signal Light

Symptom	Suspected Area	Link
Left or right front turn signal light does not operate	Headlight housing sub-assembly*2
	Headlight front turn signal LED*3
	Harness or connector	-
Left or right rear turn signal light does not operate	Rear turn signal light LED
Left or right rear turn signal light does not operate	Harness or connector	-
Left or right side turn signal light does not operate*1	Side turn signal light assembly
	Outer rear view mirror assembly
	Harness or connector	-
Turn signal lights do not operate in one direction	Turn signal switch circuit
Turn signal lights do not operate in one direction	Meter/gauge system
All turn signal lights do not operate	Turn signal switch circuit
All turn signal lights do not operate	Combination meter assembly
All turn signal lights do not flash at the correct speed	Combination meter assembly

*1: w/ Side Turn Signal Light
*2: w/ Front Turn Signal LED Socket
*3: w/o Front Turn Signal LED Socket

Hazard Warning Signal Light

Symptom	Suspected Area	Link
Hazard warning signal lights do not operate	Hazard warning switch circuit
Hazard warning signal lights do not operate	Combination meter assembly
Hazard warning signal switch do not flash	Hazard warning switch assembly
	Combination meter assembly
	Harness or connector	-

Automatic Light Control System (w/ Automatic Light Control System)

Symptom	Suspected Area	Link
Automatic light control system does not operate	Headlight dimmer switch circuit
Automatic light control system does not operate	Main body ECU (Multiplex network body ECU)

Light Auto Turn-off System

Symptom	Suspected Area	Link
Light auto turn-off system does not operate	Headlight dimmer switch circuit
	IG signal circuit
	Door courtesy switch circuit
	Main body ECU (Multiplex network body ECU)

Wiper-linked Low Beam Headlight Control System (w/ Wiper-linked Low Beam Headlight Control System)

Symptom	Suspected Area	Link
Wiper-linked low beam headlight control system does not operate	Check customize settings
	Main body ECU (Multiplex network body ECU)

Manual Headlight Beam Level Control System (w/ Manual Leveling System)

Symptom	Suspected Area	Link
Headlight beam level control does not operate	Headlight leveling switch
	Harness or connector	-
	Headlight housing sub-assembly
	Headlight leveling motor*

*: w/o Front Side Marker Light

Charge Lid Illumination (for PHEV Model)

Symptom	Suspected Area	Link
Charge lid illumination do not illuminate	Refer to the "Charge Lid Illumination Malfunction"

Terminals Of Ecu

TERMINALS OF ECU

CHECK MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) AND POWER DISTRIBUTION BOX ASSEMBLY

(a) Disconnect the power distribution box assembly and main body ECU (multiplex network body ECU) connectors.

(b) Measure the voltage and resistance according to the value(s) in the table below.

Terminal No. (Symbol)	Terminal Description	Condition	Specified Condition
z1-13 (GND1) - Body ground	Ground	Always	Below 1 Ω
z1-14 (GND2) - Body ground	Ground	Always	Below 1 Ω
z1-26 (BECU) - Body ground	Auxiliary battery power supply	Ignition switch off	11 to 14 V
z1-27 (IGR) - Body ground	Ignition power supply (IG signal)	Ignition switch ON	11 to 14 V
z1-27 (IGR) - Body ground	Ignition power supply (IG signal)	Ignition switch off	Below 1 V

(d) Measure the voltage and check for pulses according to the value(s) in the table below.

Terminal No. (Symbol)	Terminal Description	Condition	Specified Condition
K20-30 - Body ground	R shift position switch signal	Ignition switch off, reverse (R) not selected	Below 1 V
K20-30 - Body ground	R shift position switch signal	Ignition switch ON, reverse (R) selected	11 to 14 V
A12-5 - Body ground	CXPI communication line	Ignition switch off	Below 1 V
A12-5 - Body ground	CXPI communication line	Ignition switch ON	Pulse generation
A12-6 - Body ground	H-LP LH relay drive output	15 seconds or more after ignition switch turned off Taillights off	9.5 to 14 V
A12-6 - Body ground	H-LP LH relay drive output	Ignition switch ON or within 15 seconds after ignition switch turned off Taillights on	Below 1 V
A12-10 - Body ground	H-LP RH relay drive output	15 seconds or more after ignition switch turned off Taillights off	9.5 to 14 V
A12-10 - Body ground	H-LP RH relay drive output	Ignition switch ON or within 15 seconds after ignition switch turned off Taillights on	Below 1 V
A12-18 - Body ground1, 2	Taillights drive output	Taillights off	Below 1 V
A12-18 - Body ground1, 2	Taillights drive output	Taillights on	11 to 14 V
R17-30 - Body ground	Taillights drive output	Taillights off	Below 1 V
R17-30 - Body ground	Taillights drive output	Taillights on	11 to 14 V
R17-38 - Body ground	Back-up lights drive output	Ignition switch off, reverse (R) not selected	Below 1 V
R17-38 - Body ground	Back-up lights drive output	Ignition switch ON, reverse (R) selected	11 to 14 V
K17-8 (CLTB) - K17-21 (CLTE)	Automatic light control sensor power supply output	Ignition switch off	Below 1 V
K17-8 (CLTB) - K17-21 (CLTE)	Automatic light control sensor power supply output	Ignition switch ON	11 to 14 V
K17-14 (AHBI) - Body ground	Auto high beam switch signal input	Auto high beam switch off	11 to 14 V
K17-14 (AHBI) - Body ground	Auto high beam switch signal input	Auto high beam switch on	Below 1 V
K17-15 (AHID) - Body ground	Automatic light control sensor signal input	Ignition switch off	Below 1 V
K17-15 (AHID) - Body ground	Automatic light control sensor signal input	Ignition switch ON	Pulse generation (See waveform 1)
K17-20 (CLTS) - Body ground	Automatic light control sensor signal input	Ignition switch off	Below 1 V
K17-20 (CLTS) - Body ground	Automatic light control sensor signal input	Ignition switch ON	Pulse generation (See waveform 1)
K17-26 (HEAD) - Body ground	Light control switch head position input	Light control switch not in head position	11 to 14 V
K17-26 (HEAD) - Body ground	Light control switch head position input	Light control switch in head position	Below 1 V

*1: w/ Accessory Light
*2: w/ Front Side Marker Light

(1) Waveform 1

Item	Content
Tester Connection	K17-20 (CLTS) - Body ground
Tool setting	2 V/DIV., 10 ms./DIV.
Condition	Ignition switch ON

HINT:

The communication waveform changes according to the surrounding brightness.

CHECK COMBINATION METER ASSEMBLY

Click here

CHECK STEERING SENSOR

for HEV Model: Click here

for PHEV Model: Click here

CHECK SHIFT CONTROL ECU (TRANSMISSION FLOOR SHIFT ASSEMBLY)

Click here

PLUGIN CHARGE CONTROL ECU ASSEMBLY (for PHEV Model)

Click here

Data List / Active Test

DATA LIST / ACTIVE TEST

DATA LIST

NOTICE:

In the table below, the values listed under "Normal Condition" are reference values. Do not depend solely on these reference values when deciding whether a part is faulty or not.

HINT:

Using the GTS to read the Data List allows the values or states of switches, sensors, actuators and other items to be read without removing any parts. This non-intrusive inspection can be very useful because intermittent conditions or signals may be discovered before parts or wiring is disturbed. Reading the Data List information early in troubleshooting is one way to save diagnostic time.

(a) Read the Data List according to the display on the GTS.

Body Electrical > Main Body > Data List

Tester Display	Measurement Item	Normal Condition	Reference Value	Diagnostic Note
Auto High Beam Main Switch	Auto high beam switch signal	OFF or ON	OFF: Auto high beam switch not pressed ON: Auto high beam switch pressed	-
Light Control Switch (HEAD)	Light control switch head position signal	OFF or ON	OFF: Light control switch not in head position ON: Light control switch in head position	-
Insolation Amount of Solar Sensor RH	Automatic light control sensor RH condition	0 to 51100 or SensorFail	Condition can be displayed	-
Insolation Amount of Solar Sensor LH	Automatic light control sensor LH condition	0 to 51100 or SensorFail	Condition can be displayed	-
Light Sensor Illuminance	Automatic light control sensor illuminance	0 to 8191 lx or SensorFail	Value is output according to ambient light level	The displayed value is "0" when no light is detected.
AHS Function	Adaptive high beam system control function	Not Available or Available	Not Available: Adaptive high beam system control unavailable Available: Adaptive high beam system control valid	Although the item is displayed on the GTS, it is not applicable to this Toyota Prius vehicle.
High Beam Headlights (By AHS ECU)	Adaptive high beam system high beam operation status	Light OFF or Light ON	Light OFF: Adaptive high beam system high beam off Light ON: Adaptive high beam system high beam on	Although the item is displayed on the GTS, it is not applicable to this Toyota Prius vehicle.
Light Sensor Connection History	Automatic light control sensor connection status	Without or With	Without: Automatic light control sensor has not been connected With: Automatic light control sensor connected or has been connected	-
Headlight ECU Function	ECU which controls the lighting system	Not Available or Available	Not Available: Headlight ECU control unavailable Available: Headlight ECU control valid	Although the item is displayed on the GTS, it is not applicable to this Toyota Prius vehicle.
LDM ECU Function	ECU which controls the lighting system	Not Available or Available	Not Available: Light control LED ECU control unavailable Available: Light control LED ECU control valid	-
Automatic High Beam Headlights Sensor Detection Status	Automatic high beam sensor current state	Undetected, N/A, No sens, Headlight, Taillight, Speed, Daytime, Village, Other sens, Change, Out of aim, SAE Mod, Aim adjust or LIN Err	Condition can be displayed*	If the value of this item is not as specified, the automatic high beam sensor system may be malfunctioning.
Communication Power Integration No.1	Connection status between semiconductor power integration ECU and main body ECU (multiplex network body ECU)	STOP or OK	STOP: No connection OK: Connection	Although the item is displayed on the GTS, it is not applicable to this Toyota Prius vehicle.
Communication Power Integration No.2	Connection status between No. 2 semiconductor power integration ECU and main body ECU (multiplex network body ECU)	STOP or OK	STOP: No connection OK: Connection	Although the item is displayed on the GTS, it is not applicable to this Toyota Prius vehicle.
Communication Power Integration No.3	Connection status between No. 3 semiconductor power integration ECU and main body ECU (multiplex network body ECU)	STOP or OK	STOP: No connection OK: Connection	Although the item is displayed on the GTS, it is not applicable to this Toyota Prius vehicle.
Communication Power Distribution Box	Connection status between power distribution box assembly and main body ECU (multiplex network body ECU)	STOP or OK	STOP: No connection OK: Connection	When there is a malfunction, a DTC is stored
Communication LDM LH	Connection status between light control LED ECU LH and main body ECU (multiplex network body ECU)	STOP or OK	STOP: No connection OK: Connection	Although the item is displayed on the GTS, it is not applicable to this Toyota Prius vehicle.
Communication LDM RH	Connection status between light control LED ECU RH and main body ECU (multiplex network body ECU)	STOP or OK	STOP: No connection OK: Connection	Although the item is displayed on the GTS, it is not applicable to this Toyota Prius vehicle.
Tail Remind Buzzer Function	Setting of the tail remind buzzer function on/off	Disable or Enable	Customize setting displayed	-
Headlight ON in Conjunction with Wiper Function	Wiper-linked low beam headlight control	Disable or Enable	Customize setting displayed	w/ Wiper-linked Low Beam Headlight Control System
Brightness Level Adjust (Lowering)	Ambient brightness level required to dim display lights (combination meter, navigation display, etc.)	Normal, Dark2, Dark1, Light1 or Light2	Customize setting displayed	-
Brightness Level Adjust (Canceling)	Ambient brightness level required to cancel dimming display lights (combination meter, navigation display, etc.)	Normal, Dark2, Dark1, Light1 or Light2	Customize setting displayed	-
Sensitivity Adjust	Sensitivity of the automatic light control system	Normal, Dark2, Dark1, Light1 or Light2	Customize setting displayed	w/ Automatic Light Control
DRL Function	Setting of the DRL function on/off	Disable or Enable	Customize setting displayed	-
Light Auto OFF Delay Setting	Light auto OFF delay	OFF, 30sec, 60sec or 90sec	Customize setting displayed	w/ Delay Function
Sensitivity Adjust	Sensitivity of the automatic light control system (Driver 1)	Normal, Dark2, Dark1, Light1 or Light2	Customize setting displayed	w/ Automatic Light Control
DRL Function	Setting of the DRL function on/off (Driver 1)	OFF or ON	Customize setting displayed	for Toyota Prius vehicles with customize setting "DRL Function"
Light Auto OFF Delay Setting	Light auto OFF delay (Driver 1)	OFF, 30sec, 60sec or 90sec	Customize setting displayed	w/ Delay Function
Sensitivity Adjust	Sensitivity of the automatic light control system (Driver 2)	Normal, Dark2, Dark1, Light1 or Light2	Customize setting displayed	w/ Automatic Light Control
DRL Function	Setting of the DRL function on/off (Driver 2)	OFF or ON	Customize setting displayed	for Toyota Prius vehicles with customize setting "DRL Function"
Light Auto OFF Delay Setting	Light auto OFF delay (Driver 2)	OFF, 30sec, 60sec or 90sec	Customize setting displayed	w/ Delay Function
Sensitivity Adjust	Sensitivity of the automatic light control system (Driver 3)	Normal, Dark2, Dark1, Light1 or Light2	Customize setting displayed	w/ Automatic Light Control
DRL Function	Setting of the DRL function on/off (Driver 3)	OFF or ON	Customize setting displayed	for Toyota Prius vehicles with customize setting "DRL Function"
Light Auto OFF Delay Setting	Light auto OFF delay (Driver 3)	OFF, 30sec, 60sec or 90sec	Customize setting displayed	w/ Delay Function

HINT:

*: The details of each value of the Range are as follows:

Display Value	Condition	Control Condition	Diagnostic Note
Undetected	Automatic high beam sensor being initialized	Control suspended (low beam headlights illuminated)	-
N/A	Automatic high beam sensor temporarily disabled due to high temperature, unclear image (due to dirt, fog, etc.), etc.	Control suspended (previous beam setting maintained)	-
No sens	No lights detected	High beam headlights illuminated	Only when Toyota Prius vehicle speed within operation speed range
Headlight	Headlights of oncoming vehicle, etc. detected	Low beam headlights illuminated	Only when Toyota Prius vehicle speed within operation speed range
Taillight	Taillights preceding vehicle, etc. detected	Low beam headlights illuminated	Only when Toyota Prius vehicle speed within operation speed range
Speed	No lights detected and vehicle speed below operation speed	Low beam headlights illuminated	-
Daytime	Bright light detected	Low beam headlights illuminated	-
Village	Streetlights, etc. detected	Low beam headlights illuminated	Only when Toyota Prius vehicle speed within operation speed range
Change	Changing between low beams and high beams	Changing between low beams and high beams	Only when Toyota Prius vehicle speed within operation speed range
Other sens	Not applicable	-	-
Out of aim
SAE Mod
Aim adjust
LIN Err

Chassis > Steering Angle Sensor > Data List

Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
Total Distance Traveled	Actual driven distance	0 to 16777215	Roughly the same as the actual driven distance	-
Total Distance Traveled - Unit	Actual driven distance unit	km or mile	Displays the current actual driven distance unit	-
Light OFF Switch	Light control switch DRL OFF1 or off2 position signal	OFF or ON	OFF: Light control switch not in DRL OFF1 or off2 position ON: Light control switch in DRL OFF1 or off2 position	1, 2
Auto Light Switch	Light control switch AUTO3 or DRL4 position signal	OFF or ON	OFF: Light control switch not in AUTO3 or DRL4 position ON: Light control switch in AUTO3 or DRL4 position	-
Head Light Switch (Tail)	Light control switch tail position signal	OFF or ON	OFF: Light control switch in neither tail nor head position ON: Light control switch in tail or head position	-
Head Light Switch (Head)	Light control switch head position signal	OFF or ON	OFF: Light control switch not in head position ON: Light control switch in head position	-
High Beam Main Switch	Dimmer switch high position signal	OFF or ON	OFF: Dimmer switch not in high position ON: Dimmer switch in high position	-
Passing Light Switch	Dimmer switch high flash position (pass) signal	OFF or ON	OFF: Dimmer switch not in high flash position ON: Dimmer switch in high flash position	-
Auto High Beam Main Switch	Auto high beam switch signal	OFF or ON	OFF: Auto high beam switch off ON: Auto high beam switch on	Although the item is displayed on the GTS, it is not applicable to this Toyota Prius vehicle.
Turn Signal Switch (Right)	Turn signal switch (right turn position) signal	OFF or ON	OFF: Turn signal switch not in right turn position ON: Turn signal switch in right turn position	-
Turn Signal Switch (Left)	Turn signal switch (left turn position) signal	OFF or ON	OFF: Turn signal switch not in left turn position ON: Turn signal switch in left turn position	-
Cornering Light/Front Side Illuminate Light Switch	Turn signal switch (full turn) signal	OFF or ON	OFF: Turn signal switch not in left or right turn position ON: Turn signal switch in left or right full turn position	-
Front Fog Light Switch	Front fog light switch signal	OFF or ON	OFF: Front fog light switch off ON: Front fog light switch on	Although the item is displayed on the GTS, it is not applicable to this Toyota Prius vehicle.
Rear Fog Light/Bad Weather Switch	Rear fog light switch signal	OFF or ON	OFF: Rear fog light switch off ON: Rear fog light switch on	Although the item is displayed on the GTS, it is not applicable to this Toyota Prius vehicle.
Automatic Light Equipped Info	Automatic light control system specification information	Unknown, With or Without	Unknown: Specification not stored With: Automatic light control system equipped Without: Automatic light control system not equipped	-
Bad Weather Mode Equipped Info	Bad weather specification information	Unknown, Without or With	Unknown: Specification not stored Without: Bad weather specification not equipped With: Bad weather specification equipped	Although the item is displayed on the GTS, it is not applicable to this Toyota Prius vehicle.

*1: w/ DRL OFF Switch
*2: w/ OFF Switch
*3: w/ Automatic Light Control
*4: w/o Automatic Light Control

Body Electrical > Combination Meter > Data List

Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
Turn Signal Switch (Left)	Turn signal switch (left) signal	OFF or ON	OFF: Turn signal switch not in left turn position ON: Turn signal switch in left turn position	Although the item is displayed on the GTS, it is not applicable to this Toyota Prius vehicle.
Turn Signal Switch (Right)	Turn signal switch (right) signal	OFF or ON	OFF: Turn signal switch not in right turn position ON: Turn signal switch in right turn position	Although the item is displayed on the GTS, it is not applicable to this Toyota Prius vehicle.
Turn Switch Signal (Full Turn)	Turn signal switch (full turn) signal	OFF or ON	OFF: Turn signal switch not in left or right turn position ON: Turn signal switch in left or right turn position	Although the item is displayed on the GTS, it is not applicable to this Toyota Prius vehicle.
Hazard Flasher Switch	Hazard warning signal switch signal	OFF or ON	OFF: Hazard warning signal switch off ON: Hazard warning signal switch on	-
Lane Change Flashing Times Adjust	Condition of the lane change flashing times	OFF, 3, 4, 5, 6 or 7	Customize setting displayed	-

Body Electrical > Power Distribution Box > Data List

Tester Display	Measurement Item	Normal Condition	Reference Value	Diagnostic Note
Back-up Light Input Signal	Back-up light input	OFF or ON	OFF: Shift lever in any position other than R ON: Shift lever in R	-
Back-up Light Output Signal	Back-up light output	OFF or ON	OFF: Back-up light off ON: Back-up light on	-
Back-up Light Output Current	Back-up light circuit current	0.0 to 255.0 A	Below 5.3 A	Back-up light when output is on
Back-up Light Fuse Shut Off Status	Back-up light fuse shut off status	OFF or ON	OFF: Fuse has no shut off history ON: Fuse has shut off history	-
Back-up Light Fuse Shut Off Count	Back-up light fuse shut off history	0 to 255	0	-
Tail Light Internal Relay Input Signal	Taillight internal relay input	OFF or ON	OFF: Taillights off ON: Taillights on	-
Tail Light Internal Relay Output Signal	Taillight internal relay output	OFF or ON	OFF: Taillights off ON: Taillights on	-

Powertrain > Plug-in Control > Data List

Tester Display

Measurement Item

Normal Condition

Reference Value

Diagnostic Note

Charging Lid Switch Status

EV Charging lid switch status

OFF or ON

ON: Charging port lid open (push lifter of EV charger lid switch assembly extended)

OFF: Charging port lid close (push lifter of EV charger lid switch assembly pushed in)

for PHEV Model

Charging Lid Lamp Status

Charging lid light status

OFF / Fade Out / ON

OFF: Charging lid light assembly off

Fade Out: Charging lid light assembly fading out

ON: Charging lid light assembly on

for PHEV Model

ACTIVE TEST

HINT:

Using the GTS to perform Active Tests allows relays, VSVs, actuators and other items to be operated without removing any parts. This non-intrusive functional inspection can be very useful because intermittent operation may be discovered before parts or wiring is disturbed. Performing Active Tests early in troubleshooting is one way to save diagnostic time. Data List information can be displayed while performing Active Tests.

(a) Perform the Active Test according to the display on the GTS.

Body Electrical > Main Body > Active Test

Tester Display	Measurement Item	Control Range	Diagnostic Note
Headlight Relay / Light Power Supply Relay	Low beam headlights	OFF or ON	-
High Beam Headlight	High beam headlights	OFF or ON	-
Daytime Running Light	Daytime running lights	OFF or ON	-
Automatic High Beam Switch Light	Auto high beam switch indicator light	OFF or ON	-
Dimmer Signal	Dimmer signal	OFF or ON	State where circumference illumination is bright.
Rear Fog Light	Rear fog lights	OFF or ON	Although the item is displayed on the GTS, it is not applicable to this Toyota Prius vehicle.
Taillight / Clearance Light	Taillights/parking lights	OFF or ON	-

Diagnostic Trouble Code Chart

DIAGNOSTIC TROUBLE CODE CHART

Lighting System

DTC No.	Detection Item	DTC Output from	Priority
B124400	Light Sensor Circuit Malfunction	Main Body	A
B243900	Headlight LH Circuit	Main Body	A
B243A00	Headlight RH Circuit	Main Body	A
U010087	Lost Communication With ECM/PCM "A" Missing Message	Main Body	B
U010187	Lost Communication with TCM Missing Message	Main Body	B
U011187	Lost Communication with Hybrid/EV Battery Energy Control Module "A" Missing Message	Main Body	B
U012687	Lost Communication with Steering Angle Sensor Module Missing Message	Main Body	B
U012987	Lost Communication with Brake System Control Module Missing Message	Main Body	B
U015187	Lost Communication with Restraints Control Module Missing Message	Main Body	B
U015587	Lost Communication with Instrument Panel Cluster (IPC) Control Module Missing Message	Main Body	B
U016387	Lost Communication with Navigation Control Module Missing Message	Main Body	B
U016487	Lost Communication with HVAC Control Module Missing Message	Main Body	B
U016887	Lost Communication with Toyota Prius Vehicle Security Control Module Missing Message	Main Body	B
U020887	Lost Communication with "Seat Control Module A" Missing Message	Main Body	B
U023087	Lost Communication with Rear Gate Module Missing Message	Main Body	B
U023A87	Lost Communication with Image Processing Module "A" Missing Message	Main Body	B
U023B87	Lost Communication with Image Processing Module "B" Missing Message	Main Body	B
U024187	Lost Communication with Headlamp Control Module "A" Missing Message	Main Body	B
U026587	Lost Communication with Image Processing Sensor A Missing Message	Main Body	B
U029387	Lost Communication with Hybrid/EV Powertrain Control Module Missing Message	Main Body	B
U110487	Lost Communication with Driving Support ECU Missing Message	Main Body	B
U110687	Lost Communication with Electric Parking Brake Module Missing Message	Main Body	B
U110787	Lost Communication with Power Management Module Missing Message	Main Body	B
U111087	Lost Communication with Clearance Sonar Module	Main Body	B
U111787	Lost Communication with Accessory Gateway Missing Message	Main Body	B

Light Sensor Circuit Malfunction (B124400)

DESCRIPTION

The automatic light control sensor detects ambient light. The sensor creates an electrical signal based on the amount of light detected, and sends the signal to the main body ECU (multiplex network body ECU). The main body ECU (multiplex network body ECU) turns on or off the headlights and taillights according to the signal.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	DTC Output from	Priority
B124400	Light Sensor Circuit Malfunction	Detection condition: The ignition switch is ON. Malfunction status: Either of the following conditions is met: Malfunction in automatic light control sensor Open or short in automatic light control sensor circuit Malfunction duration: 5 seconds or more	Automatic light control sensor Harness or connector Main body ECU (multiplex network body ECU)	Main Body	A

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Before replacing the main body ECU (multiplex network body ECU), refer to Registration.

Click here

PROCEDURE

CLEAR DTC

(a) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

2.	CHECK FOR DTC

Pre-procedure1

(a) Turn the ignition switch to ON.

(b) Wait 10 seconds or more.

Procedure1

Body Electrical > Main Body > Trouble Codes

Result	Proceed to
B124400 is not output	A
B124400 is output	B

Post-procedure1

(d) None

USE SIMULATION METHOD TO CHECK

3.	READ VALUE USING GTS

Pre-procedure1

(a) Cover the automatic light control sensor with an opaque object.

Procedure1

(b) According to the display on the GTS, read the Data List and check that the value of Light Sensor Illuminance changes while performing the following:

(1) Slowly move the opaque object to uncover and then cover the automatic light control sensor.

Body Electrical > Main Body > Data List

Tester Display	Measurement Item	Normal Condition	Reference Value	Diagnostic Note
Light Sensor Illuminance	Automatic light control sensor illuminance	0 to 8191 lx or SensorFail	Value is output according to ambient light level	The displayed value is "0" when no light is detected.

Body Electrical > Main Body > Data List

Tester Display
Light Sensor Illuminance

OK:

The value changes according to the amount the automatic light control sensor is covered.

Post-procedure1

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

4.	CHECK HARNESS AND CONNECTOR (AUTOMATIC LIGHT CONTROL SENSOR - MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))

Pre-procedure1

(a) Disconnect the G1 automatic light control sensor connector.

(b) Disconnect the K17 main body ECU (multiplex network body ECU) connector.

Procedure1

Standard Resistance:

Click Location & Routing(G1,K17) Click Connector(G1) Click Connector(K17)

Tester Connection	Condition	Specified Condition	Result
G1-1 (CLTB) - K17-8 (CLTB)	Always	Below 1 Ω	Ω
G1-4 (CLTS) - K17-20 (CLTS)	Always	Below 1 Ω	Ω
G1-2 (CLTE) - K17-21 (CLTE)	Always	Below 1 Ω	Ω
G1-1 (CLTB) or K17-8 (CLTB) - Body ground	Always	10 kΩ or higher	kΩ
G1-4 (CLTS) or K17-20 (CLTS) - Body ground	Always	10 kΩ or higher	kΩ
G1-2 (CLTE) or K17-21 (CLTE) - Body ground	Always	10 kΩ or higher	kΩ

Post-procedure1

(d) None

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.	INSPECT MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

Pre-procedure1

(a) Connect the K17 main body ECU (multiplex network body ECU) connector.

Procedure1

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Click Location & Routing(K17) Click Connector(K17)

Tester Connection	Condition	Specified Condition	Result
K17-8 (CLTB) - K17-21 (CLTE)	Ignition switch off	Below 1 V	V
K17-8 (CLTB) - K17-21 (CLTE)	Ignition switch ON	11 to 14 V	V

Result:

Proceed to
OK
NG

*a	Component with harness connected (Main Body ECU (Multiplex Network Body ECU))

Post-procedure1

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

6.	INSPECT AUTOMATIC LIGHT CONTROL SENSOR

Click here

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

REPLACE AUTOMATIC LIGHT CONTROL SENSOR

Headlight LH Circuit (B243900,B243A00)

DESCRIPTION

The light control LED ECU supplies internally boosted voltage to the light control LED ECU so that the current supplied to the LED is always maintained at a constant value.

These DTCs are also output when the main body ECU (multiplex network body ECU) detects malfunctions while monitoring the applied voltage.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	DTC Output from	Priority
B243900	Headlight LH Circuit	Detection condition: All of the following conditions are met: Ignition switch ON Low beam headlights on Malfunction status: Headlight unit assembly malfunction Open/short in headlight LH circuit Malfunction duration: 10 seconds or more	w/ Front Side Marker Light: Headlight housing sub-assembly LH Main body ECU (multiplex network body ECU) w/o Front Side Marker Light: Headlight housing LH Light control LED ECU LH Headlight unit assembly LH Main body ECU (multiplex network body ECU)	Main Body	A
B243A00	Headlight RH Circuit	Detection condition: All of the following conditions are met: Ignition switch ON Low beam headlights on Malfunction status: Headlight unit assembly malfunction Open/short in headlight RH circuit Malfunction duration: 10 seconds or more	w/ Front Side Marker Light: Headlight housing sub-assembly RH Main body ECU (multiplex network body ECU) w/o Front Side Marker Light: Headlight housing RH Light control LED ECU RH Headlight unit assembly RH Main body ECU (multiplex network body ECU)	Main Body	A

WIRING DIAGRAM

HEADLIGHT ASSEMBLY CIRCUIT (w/o Front Side Marker Light)

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.
Before replacing the main body ECU (multiplex network body ECU), refer to Registration.
Click here
First perform the communication function inspections in How to Proceed with Troubleshooting to confirm that there are no CXPI communication malfunctions before troubleshooting this symptom.
Click here

PROCEDURE

1.	CONFIRM MODEL

(a) Choose the model to be inspected.

Result	Proceed to
w/ Front Side Marker Light	A
w/o Front Side Marker Light	B

GO TO STEP 12

CLEAR DTC

(a) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

3.	CHECK FOR DTC

Pre-procedure1

(a) Turn the ignition switch to ON.

(b) Operate the light control switch to turn on the low beam headlights and wait 10 seconds or more.

Procedure1

Body Electrical > Main Body > Trouble Codes

Result	Proceed to
B243900 is not output	A
B243900 is output	B

Post-procedure1

(d) None

GO TO STEP 9

CLEAR DTC

(a) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

5.	CHECK FOR DTC

Pre-procedure1

(a) Turn the ignition switch to ON.

(b) Operate the light control switch to turn on the low beam headlights and wait 10 seconds or more.

Procedure1

Body Electrical > Main Body > Trouble Codes

Result	Proceed to
B243A00 is not output	A
B243A00 is output	B

Post-procedure1

(d) None

USE SIMULATION METHOD TO CHECK

6.	CHECK HEADLIGHT HOUSING SUB-ASSEMBLY RH

(a) Interchange the headlight housing sub-assembly RH with LH and connect the connectors.

HINT:

Click here

CLEAR DTC

(a) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

8.	CHECK FOR DTC

Pre-procedure1

(a) Turn the ignition switch to ON.

(b) Operate the light control switch to turn on the low beam headlights and wait 10 seconds or more.

Procedure1

Body Electrical > Main Body > Trouble Codes

Result	Proceed to
B243A00 is output	A
B243A00 is not output	B

Post-procedure1

(d) None

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

REPLACE HEADLIGHT HOUSING SUB-ASSEMBLY RH

9.	CHECK HEADLIGHT HOUSING SUB-ASSEMBLY LH

(a) Interchange the headlight housing sub-assembly LH with RH and connect the connectors.

HINT:

Click here

10.

CLEAR DTC

(a) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

11.	CHECK FOR DTC

Pre-procedure1

(a) Turn the ignition switch to ON.

(b) Operate the light control switch to turn on the low beam headlights and wait 10 seconds or more.

Procedure1

Body Electrical > Main Body > Trouble Codes

Result	Proceed to
B243900 is output	A
B243900 is not output	B

Post-procedure1

(d) None

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

REPLACE HEADLIGHT HOUSING SUB-ASSEMBLY LH

12.

CLEAR DTC

(a) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

13.	CHECK FOR DTC

Pre-procedure1

(a) Turn the ignition switch to ON.

(b) Operate the light control switch to turn on the low beam headlights and wait 10 seconds or more.

Procedure1

Body Electrical > Main Body > Trouble Codes

Result	Proceed to
B243900 is not output	A
B243900 is output	B

Post-procedure1

(d) None

GO TO STEP 21

14.

CLEAR DTC

(a) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

15.	CHECK FOR DTC

Pre-procedure1

(a) Turn the ignition switch to ON.

(b) Operate the light control switch to turn on the low beam headlights and wait 10 seconds or more.

Procedure1

Body Electrical > Main Body > Trouble Codes

Result	Proceed to
B243A00 is not output	A
B243A00 is output	B

Post-procedure1

(d) None

USE SIMULATION METHOD TO CHECK

16.	CHECK HEADLIGHT HOUSING SUB-ASSEMBLY RH

(a) Interchange the headlight housing sub-assembly RH with LH and connect the connectors.

HINT:

Click here

17.

CLEAR DTC

(a) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

18.	CHECK FOR DTC

Pre-procedure1

(a) Turn the ignition switch to ON.

(b) Operate the light control switch to turn on the low beam headlights and wait 10 seconds or more.

Procedure1

Body Electrical > Main Body > Trouble Codes

Result	Proceed to
B243900 is not output	A
B243900 is output	B

Post-procedure1

(d) None

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

19.	INSPECT LIGHT CONTROL LED ECU RH

Pre-procedure1

(a) Remove the headlight housing sub-assembly RH.

HINT:

Click here

Procedure1

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection	Condition	Specified Condition	Result
A-16 - A-4	Light control switch in HEAD position	10 to 16 V	V

Result:

Proceed to
OK
NG

*a	Component with harness connected (Light Control LED ECU RH)

Post-procedure1

REPLACE LIGHT CONTROL LED ECU RH

20.	INSPECT HEADLIGHT HOUSING RH

Pre-procedure1

(a) Remove the headlight housing sub-assembly RH.

HINT:

Click here

(b) Disconnect the light control LED ECU RH connector.

Procedure1

(d) Measure the resistance according to the value(s) in the table below.

Component without harness connected

(to Light Control LED ECU RH)

Component without harness connected

(to Headlight Unit assembly RH)

Standard Resistance:

Tester Connection	Condition	Specified Condition	Result
A-16 - B-1	Always	Below 1 Ω	Ω
A-4 - B-4	Always	Below 1 Ω	Ω

Post-procedure1

(e) None

REPLACE HEADLIGHT UNIT ASSEMBLY RH

REPLACE HEADLIGHT HOUSING RH

21.	CHECK HEADLIGHT HOUSING SUB-ASSEMBLY LH

(a) Interchange the headlight housing sub-assembly LH with RH and connect the connectors.

HINT:

Click here

22.

CLEAR DTC

(a) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

23.	CHECK FOR DTC

Pre-procedure1

(a) Turn the ignition switch to ON.

(b) Operate the light control switch to turn on the low beam headlights and wait 10 seconds or more.

Procedure1

Body Electrical > Main Body > Trouble Codes

Result	Proceed to
B243900 is output	A
B243900 is not output	B

Post-procedure1

(d) None

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

24.	INSPECT LIGHT CONTROL LED ECU LH

Procedure1

(a) Remove the headlight housing sub-assembly LH.

HINT:

Click here

Post-procedure1

*a	Component with harness connected (Light Control LED ECU LH)

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection	Condition	Specified Condition	Result
A-16 - A-4	Light control switch in HEAD position	10 to 16 V	V

Pre-procedure1

REPLACE LIGHT CONTROL LED ECU LH

25.	INSPECT HEADLIGHT HOUSING LH

Pre-procedure1

(a) Remove the headlight housing sub-assembly LH.

HINT:

Click here

(b) Disconnect the light control LED ECU LH connector.

Procedure1

(d) Measure the resistance according to the value(s) in the table below.

Component without harness connected

(to Light Control LED ECU LH)

Component without harness connected

(to Headlight Unit assembly LH)

Standard Resistance:

Tester Connection	Condition	Specified Condition	Result
A-16 - B-1	Always	Below 1 Ω	Ω
A-4 - B-4	Always	Below 1 Ω	Ω

Post-procedure1

(e) None

REPLACE HEADLIGHT UNIT ASSEMBLY LH

REPLACE HEADLIGHT HOUSING LH

Lost Communication With ECM/PCM "A" Missing Message (U010087,...,U111787)

DESCRIPTION

These DTCs are stored if a CAN communication malfunction occurs between the main body ECU (multiplex network body ECU) and other ECUs.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	DTC Output from	Priority
U010087	Lost Communication With ECM/PCM "A" Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the ECM for approximately 10 seconds or more.	CAN communication system	Main Body	B
U010187	Lost Communication with TCM Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the hybrid Toyota Prius vehicle control ECU for approximately 10 seconds or more.	CAN communication system	Main Body	B
U011187	Lost Communication with Hybrid/EV Battery Energy Control Module "A" Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the hybrid Toyota Prius vehicle control ECU for approximately 10 seconds or more.	CAN communication system	Main Body	B
U012687	Lost Communication with Steering Angle Sensor Module Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the steering sensor for approximately 10 seconds or more.	CAN communication system	Main Body	B
U012987	Lost Communication with Brake System Control Module Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the No. 2 skid control ECU (brake actuator assembly) for approximately 10 seconds or more.	CAN communication system	Main Body	B
U015187	Lost Communication with Restraints Control Module Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the airbag sensor assembly for approximately 10 seconds or more.	CAN communication system	Main Body	B
U015587	Lost Communication with Instrument Panel Cluster (IPC) Control Module Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the combination meter assembly for approximately 10 seconds or more.	CAN communication system	Main Body	B
U016387	Lost Communication with Navigation Control Module Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the radio receiver assembly for approximately 10 seconds or more.	CAN communication system	Main Body	B
U016487	Lost Communication with HVAC Control Module Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the air conditioning amplifier assembly for approximately 10 seconds or more.	CAN communication system	Main Body	B
U016887	Lost Communication with Toyota Prius Vehicle Security Control Module Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the certification ECU (smart key ECU assembly) for approximately 10 seconds or more.	CAN communication system	Main Body	B
U020887	Lost Communication with "Seat Control Module A" Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the position control ECU assembly for approximately 10 seconds or more.	CAN communication system	Main Body	B
U023087	Lost Communication with Rear Gate Module Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the multiplex network door ECU for approximately 10 seconds or more.	CAN communication system	Main Body	B
U023A87	Lost Communication with Image Processing Module "A" Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the forward recognition camera for approximately 10 seconds or more.	CAN communication system	Main Body	B
U023B87	Lost Communication with Image Processing Module "B" Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the clearance warning ECU assembly for approximately 10 seconds or more.	CAN communication system	Main Body	B
U024187	Lost Communication with Headlamp Control Module "A" Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the headlight ECU sub-assembly LH for approximately 10 seconds or more.	CAN communication system	Main Body	B
U026587	Lost Communication with Image Processing Sensor A Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the rear television camera assembly for approximately 10 seconds or more.	CAN communication system	Main Body	B
U029387	Lost Communication with Hybrid/EV Powertrain Control Module Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the hybrid Toyota Prius vehicle control ECU for approximately 10 seconds or more.	CAN communication system	Main Body	B
U110487	Lost Communication with Driving Support ECU Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the forward recognition camera for approximately 10 seconds or more.	CAN communication system	Main Body	B
U110687	Lost Communication with Electric Parking Brake Module Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the No. 2 skid control ECU (brake actuator assembly) for approximately 10 seconds or more.	CAN communication system	Main Body	B
U110787	Lost Communication with Power Management Module Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the certification ECU (smart key ECU assembly) for approximately 10 seconds or more.	CAN communication system	Main Body	B
U111087	Lost Communication with Clearance Sonar Module	The main body ECU (multiplex network body ECU) does not receive data from the clearance warning ECU assembly for approximately 10 seconds or more.	CAN communication system	Main Body	B
U111787	Lost Communication with Accessory Gateway Missing Message	The main body ECU (multiplex network body ECU) does not receive data from the option connector (bus buffer ECU) for approximately 10 seconds or more.	CAN communication system	Main Body	B

PROCEDURE

CLEAR DTC

(a) Clear the DTCs.

Body Electrical > Main Body > Clear DTCs

2.	CHECK FOR DTC

Pre-procedure1

(a) Turn the ignition switch to ON.

(b) Wait 20 seconds or more.

Procedure1

Body Electrical > Main Body > Trouble Codes

Result	Proceed to
DTCs are not output	A
U010087, U010187, U011187, U012687, U012987, U015187, U015587, U016387, U016487, U016887, U020887, U023087, U023A87, U023B87, U024187, U026587, U029387, U110487, U110687, U110787, U111087 or U111787 is output	B

Post-procedure1

(d) None

USE SIMULATION METHOD TO CHECK

GO TO CAN COMMUNICATION SYSTEM

for HEV Model: Click here

for PHEV Model: Click here

Turn Signal Switch Circuit

DESCRIPTION

The steering sensor receives the turn signal switch information and controls the turn signal lights.

WIRING DIAGRAM

PROCEDURE

1.	READ VALUE USING GTS

(a) Read the Data List according to the display on the GTS.

Chassis > Steering Angle Sensor > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Turn Signal Switch (Right)

Turn signal switch (right turn position) signal

OFF or ON

OFF: Turn signal switch not in right turn position

ON: Turn signal switch in right turn position

Turn Signal Switch (Left)

Turn signal switch (left turn position) signal

OFF or ON

OFF: Turn signal switch not in left turn position

ON: Turn signal switch in left turn position

Cornering Light/Front Side Illuminate Light Switch

Turn signal switch (full turn) signal

OFF or ON

OFF: Turn signal switch not in left or right turn position

ON: Turn signal switch in left or right full turn position

Chassis > Steering Angle Sensor > Data List

Tester Display
Turn Signal Switch (Right)
Turn Signal Switch (Left)
Cornering Light/Front Side Illuminate Light Switch

OK:

Normal conditions listed above are displayed.

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

2.	INSPECT TURN SIGNAL SWITCH

Click here

REPLACE TURN SIGNAL SWITCH

3.	INSPECT STEERING WHEEL SWITCH HOUSING

Click here

REPLACE STEERING SENSOR

REPLACE STEERING WHEEL SWITCH HOUSING

Headlight Dimmer Switch Circuit

DESCRIPTION

The steering sensor receives the following switch information:

Light control switch in DRL OFF*1, OFF*2, tail, head, AUTO*3 or DRL*4 position
Dimmer switch in high, low or high flash (pass) position
- *1: w/ DRL OFF Switch
- *2: w/ OFF Switch
- *3: w/ Automatic Light Control
- *4: w/o Automatic Light Control

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Before replacing the main body ECU (multiplex network body ECU), refer to Registration.
Click here

PROCEDURE

1.	READ VALUE USING GTS

(a) Read the Data List according to the display on the GTS.

Chassis > Steering Angle Sensor > Data List

Tester Display	Measurement Item	Normal Condition	Reference Value	Diagnostic Note
Light OFF Switch	Light control switch DRL OFF1 or off2 position signal	OFF or ON	OFF: Light control switch not in DRL OFF1 or off2 position ON: Light control switch in DRL OFF1 or off2 position	1, 2
Auto Light Switch	Light control switch AUTO3 or DRL4 position signal	OFF or ON	OFF: Light control switch not in AUTO3 or DRL4 position ON: Light control switch in AUTO3 or DRL4 position	-
Head Light Switch (Tail)	Light control switch tail position signal	OFF or ON	OFF: Light control switch in neither tail nor head position ON: Light control switch in tail or head position	-
Head Light Switch (Head)	Light control switch head position signal	OFF or ON	OFF: Light control switch not in head position ON: Light control switch in head position	-
High Beam Main Switch	Dimmer switch high position signal	OFF or ON	OFF: Dimmer switch not in high position ON: Dimmer switch in high position	-
Passing Light Switch	Dimmer switch high flash position (pass) signal	OFF or ON	OFF: Dimmer switch not in high flash position ON: Dimmer switch in high flash position	-

Chassis > Steering Angle Sensor > Data List

Tester Display
Light OFF Switch
Auto Light Switch
Head Light Switch (Tail)
Head Light Switch (Head)
High Beam Main Switch
Passing Light Switch

OK:

Normal conditions listed above are displayed.

*1: w/ DRL OFF Switch
*2: w/ OFF Switch
*3: w/ Automatic Light Control
*4: w/o Automatic Light Control

GO TO STEP 5

2.	READ VALUE USING GTS

(a) Read the Data List according to the display on the GTS.

Body Electrical > Main Body > Data List

Tester Display

Measurement Item

Normal Condition

Reference Value

Diagnostic Note

Light Control Switch (HEAD)

Light control switch head position signal

OFF or ON

OFF: Light control switch not in head position

ON: Light control switch in head position

Body Electrical > Main Body > Data List

Tester Display
Light Control Switch (HEAD)

OK:

Normal conditions listed above are displayed.

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

3.	INSPECT STEERING SENSOR

Component without harness connected

(Steering Sensor)

(a) Remove the steering sensor.

Click here

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Click Location & Routing(K72,z7) Click Connector(K72) Click Connector(z7)

Tester Connection	Condition	Specified Condition
K72-7 (HEAD) - z7-4 (H)	Always	Below 1 Ω

REPLACE STEERING SENSOR

4.	CHECK HARNESS AND CONNECTOR (STEERING SENSOR - MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))

(a) Disconnect the K17 main body ECU (multiplex network body ECU) connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Click Location & Routing(K72,K17) Click Connector(K72) Click Connector(K17)

Tester Connection	Condition	Specified Condition
K72-7 (HEAD) - K17-26 (HEAD)	Always	Below 1 Ω
K72-7 (HEAD) or K17-26 (HEAD) - Body ground	Always	10 kΩ or higher

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.	INSPECT TURN SIGNAL SWITCH

Click here

REPLACE TURN SIGNAL SWITCH

6.	INSPECT STEERING WHEEL SWITCH HOUSING

Click here

REPLACE STEERING SENSOR

REPLACE STEERING WHEEL SWITCH HOUSING

Parking Light/Daytime Running Light Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) controls the parking lights and daytime running lights*.

*: w/o Front Turn Signal LED Socket

WIRING DIAGRAM

HEADLIGHT ASSEMBLY CIRCUIT (w/o Front Side Marker Light)

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.
Before replacing the main body ECU (multiplex network body ECU), refer to Registration.
Click here
First perform the communication function inspections in How to Proceed with Troubleshooting to confirm that there are no CXPI communication malfunctions before troubleshooting this symptom.
Click here

PROCEDURE

1.	CONFIRM MODEL

(a) Choose the model to be inspected.

Result	Proceed to
w/o Front Turn Signal LED Socket	A
w/ Front Turn Signal LED Socket	B

GO TO STEP 3

2.	PERFORM ACTIVE TEST USING GTS

(a) Perform the Active Test according to the display on the GTS.

Body Electrical > Main Body > Active Test

Tester Display	Measurement Item	Control Range	Diagnostic Note
Daytime Running Light	Daytime running lights	OFF or ON	-
Taillight / Clearance Light	Taillights/parking lights	OFF or ON	-

Body Electrical > Main Body > Active Test

Tester Display
Daytime Running Light

Body Electrical > Main Body > Active Test

Tester Display
Taillight / Clearance Light

OK:

Parking lights and daytime running lights illuminate.

Result	Proceed to
OK	A
NG (LH side parking light or daytime running light does not illuminate)	B
NG (RH side parking light or daytime running light does not illuminate)	C

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

REPLACE HEADLIGHT HOUSING SUB-ASSEMBLY LH

REPLACE HEADLIGHT HOUSING SUB-ASSEMBLY RH

3.	CONFIRM MODEL

(a) Choose the model to be inspected.

Result	Proceed to
w/ Front Side Marker Light	A
w/o Front Side Marker Light	B

GO TO STEP 5

4.	PERFORM ACTIVE TEST USING GTS

(a) Perform the Active Test according to the display on the GTS.

Body Electrical > Main Body > Active Test

Tester Display	Measurement Item	Control Range	Diagnostic Note
Taillight / Clearance Light	Taillights/parking lights	OFF or ON	-

Body Electrical > Main Body > Active Test

Tester Display
Taillight / Clearance Light

OK:

Parking lights illuminate.

Result	Proceed to
OK	A
NG (LH side parking light does not illuminate)	B
NG (RH side parking light does not illuminate)	C

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

REPLACE HEADLIGHT HOUSING SUB-ASSEMBLY LH

REPLACE HEADLIGHT HOUSING SUB-ASSEMBLY RH

5.	PERFORM ACTIVE TEST USING GTS

(a) Perform the Active Test according to the display on the GTS.

Body Electrical > Main Body > Active Test

Tester Display	Measurement Item	Control Range	Diagnostic Note
Taillight / Clearance Light	Taillights/parking lights	OFF or ON	-

Body Electrical > Main Body > Active Test

Tester Display
Taillight / Clearance Light

OK:

Parking lights illuminate.

Result	Proceed to
OK	A
NG (LH side parking light does not illuminate)	B
NG (RH side parking light does not illuminate)	C

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

GO TO STEP 8

6.	CHECK LIGHT CONTROL LED ECU LH

(a) Interchange the light control LED ECU LH with RH and connect the connectors.

Click here

7.	CHECK OPERATION (PARKING LIGHTS)

(a) Check the operation of the parking lights of the headlight housing sub-assembly LH.

OK:

The parking lights of the headlight housing sub-assembly LH operate normally.

REPLACE LIGHT CONTROL LED ECU LH

REPLACE HEADLIGHT HOUSING SUB-ASSEMBLY LH

8.	CHECK LIGHT CONTROL LED ECU RH

(a) Interchange the light control LED ECU RH with LH and connect the connectors.

Click here

9.	CHECK OPERATION (PARKING LIGHTS)

(a) Check the operation of the parking lights of the headlight housing sub-assembly RH.

OK:

The parking lights of the headlight housing sub-assembly RH operate normally.

REPLACE LIGHT CONTROL LED ECU RH

REPLACE HEADLIGHT HOUSING SUB-ASSEMBLY RH

Hazard Warning Switch Circuit

DESCRIPTION

The combination meter assembly receives the hazard warning signal switch assembly on signal and controls the operation of the hazard warning lights.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

When replacing the combination meter assembly, always replace it with a new one. If a combination meter assembly which was installed to another Toyota Prius vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.
When replacing the combination meter assembly, update the ECU security key.
Click here

PROCEDURE

1.	READ VALUE USING GTS

(a) Read the Data List according to the display on the GTS.

Body Electrical > Combination Meter > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Hazard Flasher Switch

Hazard warning signal switch signal

OFF or ON

OFF: Hazard warning signal switch off

ON: Hazard warning signal switch on

Body Electrical > Combination Meter > Data List

Tester Display
Hazard Flasher Switch

OK:

Normal conditions listed above are displayed.

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

2.	INSPECT HAZARD WARNING SIGNAL SWITCH ASSEMBLY

Click here

REPLACE HAZARD WARNING SIGNAL SWITCH ASSEMBLY

3.	CHECK HARNESS AND CONNECTOR (HAZARD WARNING SIGNAL SWITCH ASSEMBLY - COMBINATION METER ASSEMBLY AND BODY GROUND)

(a) Disconnect the K18 combination meter assembly connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Click Location & Routing(K18,K69) Click Connector(K18) Click Connector(K69)

Tester Connection	Condition	Specified Condition
K18-12 (HZSW) - K69-6 (HAZ)	Always	Below 1 Ω
K18-12 (HZSW) or K69-6 (HAZ) - Body ground	Always	10 kΩ or higher
K69-3 (E) - Body ground	Always	Below 1 Ω

REPLACE COMBINATION METER ASSEMBLY

REPAIR OR REPLACE HARNESS OR CONNECTOR

Back-up Light Circuit

DESCRIPTION

Shift control ECU(transmission floor shift assembly) controls the back-up lights.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE

1.	READ VALUE USING GTS

(a) Turn the ignition switch to ON.

(b) Move the shift lever to R.

Body Electrical > Power Distribution Box > Data List

Tester Display

Measurement Item

Normal Condition

Reference Value

Diagnostic Note

Back-up Light Fuse Shut Off Status

Back-up light fuse shut off status

OFF or ON

OFF: Fuse has no shut off history

ON: Fuse has shut off history

Body Electrical > Power Distribution Box > Data List

Tester Display
Back-up Light Fuse Shut Off Status

OK:

The Data List value displays "OFF".

GO TO STEP 7

2.	READ VALUE USING GTS

(a) Read the Data List according to the display on the GTS.

Body Electrical > Power Distribution Box > Data List

Tester Display

Measurement Item

Normal Condition

Reference Value

Diagnostic Note

Back-up Light Input Signal

Back-up light input

OFF or ON

OFF: Shift lever in any position other than R

ON: Shift lever in R

Body Electrical > Power Distribution Box > Data List

Tester Display
Back-up Light Input Signal

OK:

Display changes according to shift lever operation.

GO TO STEP 5

3.	CHECK HARNESS AND CONNECTOR (POWER SOURCE - POWER DISTRIBUTION BOX ASSEMBLY)

(a) Disconnect the A14 power distribution box assembly connector.

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Click Location & Routing(A14) Click Connector(A14)

Tester Connection	Condition	Specified Condition
A14-1 - Body ground	Ignition switch off	11 to 14 V

REPAIR OR REPLACE HARNESS OR CONNECTOR

4.	CHECK HARNESS AND CONNECTOR (BACK-UP LIGHT LED - POWER DISTRIBUTION BOX ASSEMBLY)

(a) Disconnect the P12 back-up light LED LH connector.

(b) Disconnect the P13 back-up light LED RH connector.

(d) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Click Location & Routing(P12,R17,P13) Click Connector(P12) Click Connector(R17) Click Connector(P13)

Tester Connection	Condition	Specified Condition
P12-1(B) - R17-38	Always	Below 1 Ω
P13-1(B) - R17-38	Always	Below 1 Ω

REPLACE POWER DISTRIBUTION BOX ASSEMBLY

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.	CHECK HARNESS AND CONNECTOR (SHIFT CONTROL ECU (TRANSMISSION FLOOR SHIFT ASSEMBLY) - POWER DISTRIBUTION BOX ASSEMBLY)

(a) Disconnect the K53 shift control ECU (transmission floor shift assembly) connector.

(b) Disconnect the K20 power distribution box assembly connector.

Standard Resistance:

Click Location & Routing(K53,K20) Click Connector(K53) Click Connector(K20)

Tester Connection	Condition	Specified Condition
K53-4(BL) - K20-30	Always	Below 1 Ω
K53-4 (BL) or K20-30 - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

6.	CHECK SHIFT CONTROL ECU (TRANSMISSION FLOOR SHIFT ASSEMBLY) (OUTPUT VOLTAGE)

*a	Component with harness connected (Power Distribution Box Assembly)

(a) Connect the K53 shift control ECU (transmission floor shift assembly) connector.

(b) Connect the K20 power distribution box assembly connector.

Standard Voltage:

Click Location & Routing(K20) Click Connector(K20)

Tester Connection	Condition	Specified Condition
K20-30 - Body ground	Ignition switch ON, reverse (R) not selected	Below 1 V
K20-30 - Body ground	Ignition switch ON, reverse (R) selected	11 to 14 V

REPLACE POWER DISTRIBUTION BOX ASSEMBLY

REPLACE SHIFT CONTROL ECU (TRANSMISSION FLOOR SHIFT ASSEMBLY)

7.	CHECK BACK-UP LIGHT LED LH

(a) Disconnect the P12 back-up light LED LH connector.

(b) Turn the ignition switch to ON.

(d) Read the Data List according to the display on the GTS.

Body Electrical > Power Distribution Box > Data List

Tester Display

Measurement Item

Normal Condition

Reference Value

Diagnostic Note

Back-up Light Fuse Shut Off Status

Back-up light fuse shut off status

OFF or ON

OFF: Fuse has no shut off history

ON: Fuse has shut off history

Body Electrical > Power Distribution Box > Data List

Tester Display
Back-up Light Fuse Shut Off Status

OK:

The Data List value displays "OFF".

REPLACE BACK-UP LIGHT LED LH

8.	CHECK BACK-UP LIGHT LED RH

(a) Disconnect the P13 back-up light LED RH connector.

(b) Turn the ignition switch to ON.

(d) Read the Data List according to the display on the GTS.

Body Electrical > Power Distribution Box > Data List

Tester Display

Measurement Item

Normal Condition

Reference Value

Diagnostic Note

Back-up Light Fuse Shut Off Status

Back-up light fuse shut off status

OFF or ON

OFF: Fuse has no shut off history

ON: Fuse has shut off history

Body Electrical > Power Distribution Box > Data List

Tester Display
Back-up Light Fuse Shut Off Status

OK:

The Data List value displays "OFF".

REPLACE BACK-UP LIGHT LED RH

REPAIR OR REPLACE HARNESS OR CONNECTOR

Charge Lid Illumination Malfunction

DESCRIPTION

The plugin charge control ECU assembly turns the spot light assembly on when the charging port lid is open and turns it off when the charging port lid is closed. The spot light assembly will turn off when the charger cable (electric vehicle charger cable assembly) is connected and turn on when the charger cable (electric Toyota Prius vehicle charger cable assembly) is disconnected.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

CAUTION:

Before the following operations are conducted, take precautions to prevent electric shock by turning the ignition switch off, wearing insulated gloves, and removing the service plug grip from HV battery.
To prevent electric shock, make sure to remove the service plug grip to cut off the high voltage circuit before servicing the Toyota Prius vehicle.
After removing the service plug grip, put it in your pocket to prevent other technicians from accidentally reconnecting it while you are working on the high-voltage system.
After removing the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals.
Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.

Click here

*a

Without waiting for 10 minutes

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE

1.	CHECK FOR DTC

(a) Enter the following menus: System Select / Health Check.

(b) Check for DTCs.

Result	Proceed to
DTCs are not output	A
DTCs are output	B

GO TO OTHER DTC CHART

2.	INSPECT PLUGIN CHARGE CONTROL ECU ASSEMBLY (CHARGE LID WITH MOTOR LOCK ASSEMBLY STATUS)

CAUTION:

Be sure to wear insulated gloves.

(a) Check that the service plug grip is not installed.

NOTICE:

After removing the service plug grip, do not turn the ignition switch to on (READY), unless instructed by the repair manual because this may cause a malfunction.

(b) Connect the cable to the negative (-) auxiliary battery terminal.

(d) Measure the voltage according to the value(s) in the table below.

HINT:

When the charging port lid is opened with all of the doors unlocked, the charging port lid is judged to be open.
When the charging port lid is closed with all of the doors locked, the charging port lid is judged to be closed.

Standard Voltage:

Click Location & Routing(R62) Click Connector(R62)

Tester Connection	Condition	Specified Condition
R62-17 (LDSW) - Body ground	Ignition switch on, charging port lid open, all doors unlocked	11 to 14 V
R62-17 (LDSW) - Body ground	Ignition switch on, charging port lid closed, all doors locked	0 to 1.5 V

(e) Turn the ignition switch off.

GO TO STEP 11

3.	INSPECT PLUGIN CHARGE CONTROL ECU ASSEMBLY (LDSW TERMINAL VOLTAGE)

(a) Disconnect the R62 plugin charge control ECU assembly connector.

(b) Turn the ignition switch to ON.

Standard Voltage:

Click Location & Routing(R62) Click Connector(R62)

Tester Connection	Condition	Specified Condition
R62-17 (LDSW) - Body ground	Ignition switch on, charging port lid open, all doors unlocked	11 to 14 V

(d) Turn the ignition switch off.

GO TO STEP 11

4.	READ VALUE USING GTS

CAUTION:

Be sure to wear insulated gloves.

(a) Check that the service plug grip is not installed.

NOTICE:

After removing the service plug grip, do not turn the ignition switch to on (READY), unless instructed by the repair manual because this may cause a malfunction.

(b) Connect the R62 plugin charge control ECU assembly connector.

HINT:

When the charging port lid is opened with all of the doors unlocked, the charging port lid is judged to be open.
When the charging port lid is closed with all of the doors locked, the charging port lid is judged to be closed.

Standard Voltage:

Click Location & Routing(R62) Click Connector(R62)

Tester Connection	Condition	Specified Condition
R62-17 (LDSW) - Body ground	Ignition switch on, charging port lid open, all doors unlocked	11 to 14 V
R62-17 (LDSW) - Body ground	Ignition switch on, charging port lid closed, all doors locked	0 to 1.5 V

(d) Read the Data List according to the display on the GTS.

Powertrain > Plug-in Control > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Charging Lid Switch Status

Charge lid with motor lock assembly status

OFF or ON

OFF: Charging port lid closed

ON: Charging port lid open

Powertrain > Plug-in Control > Data List

Tester Display
Charging Lid Switch Status

HINT:

The Data List allows the state of the inspection terminal to be read.
As the value of the Data List may vary when taking measurements due to factors such as the environment, Toyota Prius vehicle age, etc., the result should be used as a reference only.

(e) Turn the ignition switch off.

Result	Proceed to
The Data List item and voltage change accordingly	A
The Data List item and voltage do not change accordingly	B

REPLACE PLUGIN CHARGE CONTROL ECU ASSEMBLY

5.	INSPECT PLUGIN CHARGE CONTROL ECU ASSEMBLY (SPOT LIGHT ASSEMBLY STATUS)

CAUTION:

Be sure to wear insulated gloves.

(a) Check that the service plug grip is not installed.

NOTICE:

After removing the service plug grip, do not turn the ignition switch to on (READY), unless instructed by the repair manual because this may cause a malfunction.

(b) Turn the ignition switch to ON.

HINT:

When the charging port lid is opened with all of the doors unlocked, the charging port lid is judged to be open.
When the charging port lid is closed with all of the doors locked, the charging port lid is judged to be closed.

Standard Voltage:

Click Location & Routing(R62) Click Connector(R62)

Tester Connection	Condition	Specified Condition
R62-18 (LDLP) - Body ground	Ignition switch on, charging port lid closed, all doors locked	0 to 1.5 V

(d) Turn the ignition switch off.

GO TO STEP 8

6.	INSPECT PLUGIN CHARGE CONTROL ECU ASSEMBLY (LDLP TERMINAL VOLTAGE)

(a) Disconnect the R62 plugin charge control ECU assembly connector.

(b) Turn the ignition switch to ON.

Standard Voltage:

Click Location & Routing(R62) Click Connector(R62)

Tester Connection	Condition	Specified Condition
R62-18 (LDLP) - Body ground	Ignition switch on, charging port lid open, all doors unlocked	5 to 14 V

(d) Turn the ignition switch off.

GO TO STEP 8

7.	READ VALUE USING GTS

CAUTION:

Be sure to wear insulated gloves.

(a) Check that the service plug grip is not installed.

NOTICE:

After removing the service plug grip, do not turn the ignition switch to on (READY), unless instructed by the repair manual because this may cause a malfunction.

(b) Connect the R62 plugin charge control ECU assembly connector.

HINT:

The spot light assembly illuminates when the charging port lid is opened with all of the doors unlocked.
When any of the following conditions is met, the spot light assembly turns off.
- The charging port lid is open and the spot light assembly is illuminated for 20 minutes or more.
- The charge plug is connected when the charging port lid open. (The spot light assembly turns off 7.5 seconds after the charge plug is connected.)
The charging port lid is closed with all of the doors locked.

Standard Voltage:

Click Location & Routing(R62) Click Connector(R62)

Tester Connection	Condition	Specified Condition
R62-18 (LDLP) - Body ground	Ignition switch on, charging port lid closed, spot light assembly not illuminated	0 to 1.5 V
R62-18 (LDLP) - Body ground	Ignition switch on, charging port lid open, spot light assembly not illuminated	5 to 14 V
R62-18 (LDLP) - Body ground	Ignition switch on, charging port lid open, spot light assembly illuminated	0 to 5 V

(d) Enter the following menus: Powertrain / Plug-in Control / Data List.

(e) Read the Data List according to the display on the GTS.

Powertrain > Plug-in Control > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Charging Lid Lamp Status

Spot light assembly status

OFF, Fade Out or ON

OFF: Spot light assembly off

Fade Out: Spot light assembly fading out

ON: Spot light assembly on

Powertrain > Plug-in Control > Data List

Tester Display
Charging Lid Lamp Status

HINT:

The Data List allows the state of the inspection terminal to be read.
As the value of the Data List may vary when taking measurements due to factors such as the environment, Toyota Prius vehicle age, etc., the result should be used as a reference only.

Result	Proceed to
The Data List item value is OFF and the voltage is 0 to 1.5 V The Data List item value is Fade Out and the voltage is 5 to 14 V The Data List item value is ON and the voltage is 0 to 5 V	A
Other than above	B

GO TO CAUSE ANALYSIS (USER RELATED CAUSE)

(a) Perform cause analysis as specified in the following table.

Possible Cause

Action to be Taken

Entry function of smart key system disabled

Explain to the customer that as the entry function was disabled, it did not operate even when the electrical key transmitter sub-assembly was brought near the charging port lid.

HINT:

Conditions in which the spot light assembly illuminates when the entry function is disabled:
When the charging port lid is opened, the charge plug is connected or the charge plug is disconnected.
Conditions in which the spot light assembly turns off when the entry function is disabled:
When the charging port lid is closed, the charge plug is locked, the ignition switch is on (READY), rapid charging is started or a certain period of time has elapsed since the spot light assembly illuminated.

Charging connector lock was operated repeatedly

Explain to the customer the spot light assembly will not illuminate if the push lifter of the charge lid with motor lock assembly (charging lid courtesy switch) is pushed in (the charging port lid is judged as closed).

(b) Take appropriate action in accordance with the result of the cause analysis.

REPLACE PLUGIN CHARGE CONTROL ECU ASSEMBLY

8.	INSPECT SPOT LIGHT ASSEMBLY

Click here

REPLACE SPOT LIGHT ASSEMBLY

9.	CHECK HARNESS AND CONNECTOR (CHARGE LID WITH MOTOR LOCK ASSEMBLY - SPOT LIGHT ASSEMBLY)

(a) Disconnect the R30 charge lid with motor lock assembly connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Click Location & Routing(R30,R41) Click Connector(R30) Click Connector(R41)

Tester Connection	Condition	Specified Condition
R30-2 (LDSW) - R41-2 (LP)	Always	Below 1 Ω
R30-2 (LDSW) or R41-2 (LP) - Body ground	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR

10.	CHECK HARNESS AND CONNECTOR (SPOT LIGHT ASSEMBLY - PLUGIN CHARGE CONTROL ECU ASSEMBLY)

(a) Disconnect the R62 plugin charge control ECU assembly connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Click Location & Routing(R41,R62) Click Connector(R41) Click Connector(R62)

Tester Connection	Condition	Specified Condition
R41-1 (LDLP) - R62-18 (LDLP)	Always	Below 1 Ω
R41-1 (LDLP) or R62-18 (LDLP) - Body ground	Always	10 kΩ or higher

REPLACE PLUGIN CHARGE CONTROL ECU ASSEMBLY

REPAIR OR REPLACE HARNESS OR CONNECTOR

11.	INSPECT CHARGE LID WITH MOTOR LOCK ASSEMBLY

Click here

REPLACE CHARGE LID WITH MOTOR LOCK ASSEMBLY

12.	CHECK HARNESS AND CONNECTOR (AUXILIARY BATTERY - CHARGE LID WITH MOTOR LOCK ASSEMBLY)

(a) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Click Location & Routing(R30) Click Connector(R30)

Tester Connection	Condition	Specified Condition
R30-1 ( B) - Body ground	Ignition switch off	11 to 14 V

REPAIR OR REPLACE HARNESS OR CONNECTOR

13.	CHECK HARNESS AND CONNECTOR (CHARGE LID WITH MOTOR LOCK ASSEMBLY - PLUGIN CHARGE CONTROL ECU ASSEMBLY)

(a) Disconnect the R62 plugin charge control ECU assembly connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Click Location & Routing(R30,R62) Click Connector(R30) Click Connector(R62)

Tester Connection	Condition	Specified Condition
R30-2 (LDSW) - R62-17 (LDSW)	Always	Below 1 Ω
R30-2 (LDSW) or R62-17 (LDSW) - Body ground	Always	10 kΩ or higher

REPLACE PLUGIN CHARGE CONTROL ECU ASSEMBLY

REPAIR OR REPLACE HARNESS OR CONNECTOR

LO-beam Headlight does not Illuminate

DESCRIPTION

The main body ECU (multiplex network body ECU) controls the low beam headlights.

WIRING DIAGRAM

HEADLIGHT ASSEMBLY CIRCUIT (w/o Front Side Marker Light)

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.
Before replacing the main body ECU (multiplex network body ECU), refer to Registration.
Click here
First perform the communication function inspections in How to Proceed with Troubleshooting to confirm that there are no CXPI communication malfunctions before troubleshooting this symptom.
Click here

PROCEDURE

1.	CONFIRM MODEL

(a) Choose the model to be inspected.

Result	Proceed to
w/ Front Side Marker Light	A
w/o Front Side Marker Light	B

GO TO STEP 3

2.	PERFORM ACTIVE TEST USING GTS

(a) Perform the Active Test according to the display on the GTS.

Body Electrical > Main Body > Active Test

Tester Display	Measurement Item	Control Range	Diagnostic Note
Headlight Relay / Light Power Supply Relay	Low beam headlights	OFF or ON	-

Body Electrical > Main Body > Active Test

Tester Display
Headlight Relay / Light Power Supply Relay

OK:

Low beam headlights illuminate.

Result	Proceed to
OK	A
NG (LH side low beam headlight does not illuminate)	B
NG (RH side low beam headlight does not illuminate)	C

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

REPLACE HEADLIGHT HOUSING SUB-ASSEMBLY LH

REPLACE HEADLIGHT HOUSING SUB-ASSEMBLY RH

3.	PERFORM ACTIVE TEST USING GTS

(a) Perform the Active Test according to the display on the GTS.

Body Electrical > Main Body > Active Test

Tester Display	Measurement Item	Control Range	Diagnostic Note
Headlight Relay / Light Power Supply Relay	Low beam headlights	OFF or ON	-

Body Electrical > Main Body > Active Test

Tester Display
Headlight Relay / Light Power Supply Relay

OK:

Low beam headlights illuminate.

Result	Proceed to
OK	A
NG (LH side low beam headlight does not illuminate)	B
NG (RH side low beam headlight does not illuminate)	C

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

GO TO STEP 6

4.	INSPECT LIGHT CONTROL LED ECU LH

(a) Remove the headlight housing sub-assembly LH.

Click here

*a	Component with harness connected (Light Control LED ECU LH)

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection	Condition	Specified Condition
A-16 - A-4	Light control switch in HEAD position	10 to 16 V

REPLACE LIGHT CONTROL LED ECU LH

5.	INSPECT HEADLIGHT HOUSING LH

(a) Remove the headlight housing sub-assembly LH.

Click here

(b) Disconnect the light control LED ECU LH connector.

(d) Measure the resistance according to the value(s) in the table below.

Component without harness connected

(to Light Control LED ECU LH)

Component without harness connected

(to Headlight Unit assembly LH)

Standard Resistance:

Tester Connection	Condition	Specified Condition
A-16 - B-1	Always	Below 1 Ω
A-4 - B-4	Always	Below 1 Ω

REPLACE HEADLIGHT UNIT ASSEMBLY LH

REPLACE HEADLIGHT HOUSING LH

6.	INSPECT LIGHT CONTROL LED ECU RH

(a) Remove the headlight housing sub-assembly RH.

Click here

*a	Component with harness connected (Light Control LED ECU RH)

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection	Condition	Specified Condition
A-16 - A-4	Light control switch in HEAD position	10 to 16 V

REPLACE LIGHT CONTROL LED ECU RH

7.	INSPECT HEADLIGHT HOUSING RH

(a) Remove the headlight housing sub-assembly RH.

Click here

(b) Disconnect the light control LED ECU RH connector.

(d) Measure the resistance according to the value(s) in the table below.

Component without harness connected

(to Light Control LED ECU RH)

Component without harness connected

(to Headlight Unit assembly RH)

Standard Resistance:

Tester Connection	Condition	Specified Condition
A-16 - B-1	Always	Below 1 Ω
A-4 - B-4	Always	Below 1 Ω

REPLACE HEADLIGHT UNIT ASSEMBLY RH

REPLACE HEADLIGHT HOUSING RH

Taillight Relay Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) controls the operation of the TAIL relay.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.
Before replacing the main body ECU (multiplex network body ECU), refer to Registration.
Click here
First perform the communication function inspections in How to Proceed with Troubleshooting to confirm that there are no CXPI communication malfunctions before troubleshooting this symptom.
Click here

PROCEDURE

1.	PERFORM ACTIVE TEST USING GTS

(a) Read the Data List according to the display on the GTS.

Body Electrical > Main Body > Active Test

Tester Display	Measurement Item	Control Range	Diagnostic Note
Taillight / Clearance Light	Taillights/parking lights	OFF or ON	-

Body Electrical > Main Body > Active Test

Tester Display
Taillight / Clearance Light

OK:

taillights illuminate.

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

2.	CHECK HARNESS AND CONNECTOR (POWER SOURCE - POWER DISTRIBUTION BOX ASSEMBLY)

(a) Disconnect the A15 power distribution box assembly connector.

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Click Location & Routing(A15) Click Connector(A15)

Tester Connection	Condition	Specified Condition
A15-1 - Body ground	Ignition switch off	11 to 14 V

REPAIR OR REPLACE HARNESS OR CONNECTOR

3.	CHECK HARNESS AND CONNECTOR (TAILLIGHT CIRCUIT)

(a) Disconnect the B8 LED illumination light LH connector. (w/ Accessory Light)

(b) Disconnect the B11 LED illumination light RH connector. (w/ Accessory Light)

(d) Disconnect the B9 front marker light assembly RH connector. (w/ Front Side Marker Light)

(e) Disconnect the m2 tail light LED (LH) connector. (w/ Tail Light LED)

(f) Disconnect the m3 tail light LED (RH) connector. (w/ Tail Light LED)

(g) Disconnect the S1 rear combination light lens and body LH connector.

(h) Disconnect the S2 rear combination light lens and body RH connector.

(i) Disconnect the P10 rear side marker light assembly LH connector. (w/ Rear Side Marker Light)

(j) Disconnect the P9 rear side marker light assembly RH connector. (w/ Rear Side Marker Light)

(k) Disconnect the P8 license plate light assembly LH connector.

(l) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Click Location & Routing(S1,R17,B8,B10,A12) Click Connector(S1) Click Connector(R17) Click Connector(B8) Click Connector(B10) Click Connector(A12)

Tester Connection	Condition	Specified Condition
S1-3 (TL) - R17-30	Always	Below 1 Ω
B8-1 (B)1 or B10-2 (B)2 - A12-181, 2	Always	Below 1 Ω
S1-3 (TL) or R17-30 - Body ground	Always	10 kΩ or higher
B8-1 (B)1, B10-2 (B)2 or A12-18 - Body ground1, 2	Always	10 kΩ or higher

*1: w/ Accessory Light
*2: w/ Rear Side Marker Light

REPAIR OR REPLACE HARNESS OR CONNECTOR

4.	CHECK POWER DISTRIBUTION BOX ASSEMBLY

(a) Connect the A15 power distribution box assembly connector.

(b) Connect the R17 power distribution box assembly connector.

*1: w/ Accessory Light
*2: w/ Front Side Marker Light

(d) Turn the light control switch to the tail position.

(e) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Click Location & Routing(R17) Click Connector(R17)

Tester Connection	Condition	Specified Condition
R17-30 - Body ground	Ignition switch off	11 to 14 V

Result	Proceed to
OK (w/ Front Side Marker Light)	A
OK (w/o Front Side Marker Light)	B
NG	C

GO TO STEP 9

REPLACE POWER DISTRIBUTION BOX ASSEMBLY

5.	CHECK FRONT MARKER LIGHT ASSEMBLY LH

(a) Connect the B10 front marker light assembly LH connector.

(b) Turn the light control switch to the tail position.

Standard Voltage:

Click Location & Routing(S1) Click Connector(S1)

Tester Connection	Condition	Specified Condition
S1-3 (TL) - Body ground	Ignition switch off	11 to 14 V

REPLACE FRONT MARKER LIGHT ASSEMBLY LH

6.	CHECK FRONT MARKER LIGHT ASSEMBLY RH

(a) Connect the B9 front marker light assembly RH connector.

(b) Turn the light control switch to the tail position.

Standard Voltage:

Click Location & Routing(S1) Click Connector(S1)

Tester Connection	Condition	Specified Condition
S1-3 (TL) - Body ground	Ignition switch off	11 to 14 V

Result	Proceed to
OK (w/ Accessory Light)	A
OK (w/o Accessory Light)	B
NG	C

GO TO STEP 9

REPLACE FRONT MARKER LIGHT ASSEMBLY RH

7.	CHECK LED ILLUMINATION LIGHT LH

(a) Connect the B8 LED illumination light LH connector.

(b) Turn the light control switch to the tail position.

Standard Voltage:

Click Location & Routing(S1) Click Connector(S1)

Tester Connection	Condition	Specified Condition
S1-3 (TL) - Body ground	Ignition switch off	11 to 14 V

REPLACE LED ILLUMINATION LIGHT LH

8.	CHECK LED ILLUMINATION LIGHT RH

(a) Connect the B11 LED illumination light RH connector.

(b) Turn the light control switch to the tail position.

Standard Voltage:

Click Location & Routing(S1) Click Connector(S1)

Tester Connection	Condition	Specified Condition
S1-3 (TL) - Body ground	Ignition switch off	11 to 14 V

GO TO STEP 9

REPLACE LED ILLUMINATION LIGHT RH

9.	CHECK REAR COMBINATION LIGHT LENS AND BODY LH

(a) Connect the S1 rear combination light lens and body LH connector.

(b) Turn the light control switch to the tail position.

Standard Voltage:

Click Location & Routing(P8) Click Connector(P8)

Tester Connection	Condition	Specified Condition
P8-1 (B) - Body ground	Ignition switch off	11 to 14 V

REPLACE REAR COMBINATION LIGHT LENS AND BODY LH

10.	CHECK REAR COMBINATION LIGHT LENS AND BODY RH

(a) Connect the S2 rear combination light lens and body RH connector.

(b) Turn the light control switch to the tail position.

Standard Voltage:

Click Location & Routing(P8) Click Connector(P8)

Tester Connection	Condition	Specified Condition
P8-1 (B) - Body ground	Ignition switch off	11 to 14 V

Result	Proceed to
OK (w/ Rear Side Marker Light)	A
OK (w/o Rear Side Marker Light)	B
NG	C

REPLACE LICENSE PLATE LIGHT ASSEMBLY

REPLACE REAR COMBINATION LIGHT LENS AND BODY RH

11.	CHECK REAR SIDE MARKER LIGHT ASSEMBLY LH

(a) Connect the P10 rear side marker light assembly LH connector.

(b) Turn the light control switch to the tail position.

Standard Voltage:

Click Location & Routing(P8) Click Connector(P8)

Tester Connection	Condition	Specified Condition
P8-1 (B) - Body ground	Ignition switch off	11 to 14 V

REPLACE REAR SIDE MARKER LIGHT ASSEMBLY LH

12.	CHECK REAR SIDE MARKER LIGHT ASSEMBLY RH

(a) Connect the P9 rear side marker light assembly RH connector.

(b) Turn the light control switch to the tail position.

Standard Voltage:

Click Location & Routing(P8) Click Connector(P8)

Tester Connection	Condition	Specified Condition
P8-1 (B) - Body ground	Ignition switch off	11 to 14 V

Result	Proceed to
OK (w/ Tail Light LED)	A
OK (w/o Tail Light LED)	B
NG	C

REPLACE LICENSE PLATE LIGHT ASSEMBLY

REPLACE REAR SIDE MARKER LIGHT ASSEMBLY RH

13.	CHECK TAIL LIGHT LED (LH)

(a) Connect the m2 tail light LED (LH) connector.

(b) Turn the light control switch to the tail position.

Standard Voltage:

Click Location & Routing(P8) Click Connector(P8)

Tester Connection	Condition	Specified Condition
P8-1 (B) - Body ground	Ignition switch off	11 to 14 V

REPLACE TAIL LIGHT LED (LH)

14.	CHECK TAIL LIGHT LED (RH)

(a) Connect the m3 tail light LED (RH) connector.

(b) Turn the light control switch to the tail position.

Standard Voltage:

Click Location & Routing(P8) Click Connector(P8)

Tester Connection	Condition	Specified Condition
P8-1 (B) - Body ground	Ignition switch off	11 to 14 V

REPLACE LICENSE PLATE LIGHT ASSEMBLY

REPLACE TAIL LIGHT LED (RH)

High Beam Headlight Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) controls the high beam headlights.

WIRING DIAGRAM

HEADLIGHT ASSEMBLY CIRCUIT (w/o Front Side Marker Light)

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.
Before replacing the main body ECU (multiplex network body ECU), refer to Registration.
Click here
First perform the communication function inspections in How to Proceed with Troubleshooting to confirm that there are no CXPI communication malfunctions before troubleshooting this symptom.
Click here