Toyota Prius: Grille Shutter System

Toyota Prius (XW60) 2023-2025 Service Manual / Vehicle Exterior / Exterior Panels / Trim / Grille Shutter System

Parts Location
System Diagram
System Description
How To Proceed With Troubleshooting
Problem Symptoms Table
Grille Shutter does not Operate
Grille Shutter is Half Opened/Closed

Parts Location

PARTS LOCATION

ILLUSTRATION

RADIATOR SHUTTER ASSEMBLY

- SWING GRILLE ACTUATOR ASSEMBLY

ECM

NO. 1 ENGINE ROOM RELAY BLOCK AND NO. 1 JUNCTION BLOCK ASSEMBLY

- EFI NO.4 FUSE

EXTENSION WIRE ASSEMBLY

System Diagram

SYSTEM DIAGRAM

System Description

SYSTEM DESCRIPTION

GRILLE SHUTTER SYSTEM

(a) General description

The swing grille actuator assembly receives signals from the ECM via LIN communication. Based on these signals, the swing grille actuator assembly operates the radiator shutter assembly.

(b) Control List

Control	Description
Closing Operation Control	The grille shutter closes when certain conditions related to the Toyota Prius vehicle speed, engine coolant temperature, inverter coolant temperature, ambient temperature and refrigerant pressure are met.
Opening Operation Control	The grille shutter opens when certain conditions related to the Toyota Prius vehicle speed, engine coolant temperature, inverter coolant temperature, ambient temperature and refrigerant pressure are met.
Ignition Switch Off-linked Opening Operation Control	Opens the grille shutter when the ignition switch is turned off in order to prevent the grille shutter from becoming stuck closed while the Toyota Prius vehicle is stopped.
Retry Operation	If a mechanical malfunction is detected during a grille shutter operation, the operation will be attempted again.

How To Proceed With Troubleshooting

CAUTION / NOTICE / HINT

HINT:

Use these procedures to troubleshoot the grille shutter 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 FOR DTC*

Check for DTCs.

Powertrain > Engine > Trouble Codes

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

GO TO DIAGNOSTIC TROUBLE CODE CHART

6.	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 STEP 8

7.	OVERALL ANALYSIS AND TROUBLESHOOTING*

(a) Terminals of ECU

Click here

(b) Data List / Active Test

Click here

8.	ADJUST, REPAIR OR REPLACE

9.	CHECK FOR DTC*

(a) Clear the DTCs.

Powertrain > Engine > Clear DTCs

(b) Check for DTCs.

Powertrain > Engine > Trouble Codes

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

END

GO TO DIAGNOSTIC TROUBLE CODE CHART

Problem Symptoms Table

PROBLEM SYMPTOMS TABLE

NOTICE:

Before performing troubleshooting, change the grille shutter control mode to maintenance mode.
Click here
If the radiator shutter assembly has been replaced with a new one, perform initialization and change the grille shutter control mode.
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.
Inspect the fuses and relays related to this system before inspecting the suspected areas below.

Symptom	Suspected Area	Link
Grille shutter does not operate	Proceed to "Grille Shutter does not Operate"
Grille shutter does not operate	Radiator shutter assembly
Grille shutter is half open (half closed)	Proceed to "Grille Shutter is Half Opened/Closed"
Abnormal noise occurs during grille shutter operation	Check for ice, etc. around the shutters and links	-
Abnormal noise occurs during grille shutter operation	Radiator shutter assembly

Grille Shutter does not Operate

DESCRIPTION

The radiator shutter assembly may not operate due to foreign matter, such as snow or dirt, or a drop in voltage.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Before performing troubleshooting, change the grille shutter control mode to maintenance mode.
Click here
If the radiator shutter assembly has been replaced with a new one, perform initialization and change the grille shutter control mode.
Click here
Inspect the fuses for circuits related to this system before performing the following procedure.

PROCEDURE

1.	PERFORM UTILITY USING GTS (SWITCH GRILLE SHUTTER CONTROL MODE)

(a) According to the display on the GTS, change the grille shutter control mode from normal mode to maintenance mode.

Powertrain > Engine > Utility

Tester Display
Switch Grille Shutter Control Mode

2.	CHECK FOR GRILLE SHUTTER (FOREIGN MATTER AND ICE)

(a) Check the area around the shutters and the links of the grille shutter for foreign matter and ice.

OK:

The radiator shutter assembly is free of foreign matter and ice.

FOREIGN OBJECT (REMOVE FOREIGN MATTER AND/OR ICE)

3.	CHECK RADIATOR SHUTTER ASSEMBLY

(a) Remove the radiator shutter assembly.

Click here

(b) While using fingers to pinch the fin at the location shown in the illustration, fully open and close the radiator shutter assembly manually and check that it moves smoothly.

HINT:

If the fin is pinched with fingers far from the swing grille actuator assembly, the function may not be able to be inspected correctly.

Swing Grille Actuator Assembly

Fin

OK:

The radiator shutter assembly moves smoothly.

REPLACE RADIATOR SHUTTER ASSEMBLY

CLEAR DTC

(a) Clear the DTCs.

Powertrain > Engine > Clear DTCs

(b) Turn the ignition switch off and wait for at least 30 seconds.

5.	CHECK FOR DTC

(a) Check for DTCs.

Powertrain > Engine > Trouble Codes

OK:

DTCs are not output.

GO TO SFI SYSTEM

6.	CHECK HARNESS AND CONNECTOR (EXTENSION WIRE ASSEMBLY - POWER SUPPLY AND BODY GROUND)

(a) Disconnect the Ai1 extension wire assembly connector.

*a	Component without harness connected (to Extension Wire Assembly)

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

Standard Voltage:

Click Location & Routing(Ai1) Click Connector(Ai1)

Tester Connection	Switch Condition	Specified Condition
Ai1-1 ( B) - Ai1-3 (GND)	Ignition switch ON	11 to 14 V

REPAIR OR REPLACE HARNESS OR CONNECTOR

7.	INSPECT EXTENSION WIRE ASSEMBLY

(a) Remove the extension wire assembly.

Click here

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

Standard Resistance:

Click Location & Routing(i1,Ai1) Click Connector(i1) Click Connector(Ai1)

Tester Connection	Switch Condition	Specified Condition
i1-1 ( B) - Ai1-1 ( B)	Always	Below 1 Ω
i1-3 (GND) - Ai1-3 (GND)	Always	Below 1 Ω

Component without harness connected

(to Radiator Shutter Assembly)

Component without harness connected

(to Wire Harness)

REPLACE RADIATOR SHUTTER ASSEMBLY

REPLACE EXTENSION WIRE ASSEMBLY

Grille Shutter is Half Opened/Closed

DESCRIPTION

The radiator shutter assembly may be half open (half closed) due to foreign matter, such as snow or dirt.

CAUTION / NOTICE / HINT

NOTICE:

Before performing troubleshooting, change the grille shutter control mode to maintenance mode.
Click here
If the radiator shutter assembly has been replaced with a new one, perform initialization and change the grille shutter control mode.
Click here

PROCEDURE

1.	PERFORM UTILITY USING GTS (SWITCH GRILLE SHUTTER CONTROL MODE)

(a) According to the display on the GTS, change the grille shutter control mode from normal mode to maintenance mode.

Click here

Powertrain > Engine > Utility

Tester Display
Switch Grille Shutter Control Mode

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

Powertrain > Engine > Data List

Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
Grille Shutter Control Mode	Grille shutter control mode status	Normal or Maintenance	Normal: Normal mode Maintenance: Maintenance mode	-

Powertrain > Engine > Data List

Tester Display
Grille Shutter Control Mode

2.	CHECK FOR FOREIGN OBJECT

(a) Check that the radiator shutter assembly is free of foreign matter and ice.

OK:

The radiator shutter assembly is free of foreign matter and ice.

FOREIGN OBJECT (REMOVE FOREIGN MATTER AND/OR ICE)

3.	PERFORM UTILITY USING GTS (GRILLE SHUTTER INITIALIZATION)

HINT:

When changing the grille shutter control mode and/or performing initialization by driving the Toyota Prius vehicle, the grille shutter control mode can only be changed and initialization can only be performed if the grille shutter system is in maintenance mode.

Click here

(a) According to the display on the GTS, perform Grille Shutter Initialization.

Powertrain > Engine > Utility

Tester Display
Grille Shutter Initialization

4.	PERFORM ACTIVE TEST USING GTS (CONTROL THE GRILLE SHUTTER)

(a) Use the GTS to perform Active Test to operate the grille shutter and remove any foreign matter.

HINT:

If foreign matter is trapped on the opening side, move the grille shutter in the closing direction. If foreign matter is trapped on the closing side, move the grille shutter in the opening direction.

Powertrain > Engine > Active Test

Tester Display	Measurement Item	Control Range	Diagnostic Note
Control the Grille Shutter	Control the swing grille actuator	0% (open) to 100% (close)	Perform this test when the following conditions are met: Ignition switch ON Auxiliary battery voltage 10.5 to 16 V