Turn Signal Light Circuit

LIGHTING (EXT): LIGHTING SYSTEM: Turn Signal Light Circuit
- Turn Signal Light Circuit

DESCRIPTION

The main body ECU LH controls the operation of the turn signal flasher assembly. The turn signal flasher assembly blinks the turn signal lights.

The main body ECU LH receives RH/LH turn signal light blink request signals from the combination switch ECU through BEAN communication and sends operation signals to the turn signal flasher assembly.

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1. CHECK TURN SIGNAL LIGHT (OPERATION)

(a) Turn the engine switch on (IG).

(b) When the turn signal light switch is operated, check that the corresponding turn signal lights flash.

HINT
The front and rear turn signal lights share the same drive circuit. Therefore, if either the front or rear turn signal lights do not come on, there may be a problem in the circuit between the turn signal flasher and a bulb, or the circuit between a bulb and body ground.

Result:

B -- PERFORM ACTIVE TEST USING TECHSTREAM

C -- PERFORM ACTIVE TEST USING TECHSTREAM
A -- Continue to next step.

2. PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Body No. 3 / Active Test.

(e) Check that the turn signal lights operate.

Body No. 3 (Main Body ECU LH)

OK:

Turn signal lights flash.

NG -- INSPECT FUSE (LH-IG, TURN-HAZ)

OK -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Exterior Lighting System

3. INSPECT FUSE (LH-IG, TURN-HAZ)

(a) Remove the LH-IG fuse from the cowl side junction block LH.

(b) Remove the TURN-HAZ fuse from the No. 1 engine room junction block.

(c) Measure the resistance of the fuses.

Standard Resistance:

Below 1 Ohms

NG -- REPLACE FUSE
OK -- Continue to next step.

4. CHECK HARNESS AND CONNECTOR (POWER SOURCE)

(a) Disconnect the J30 flasher assembly connector.

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

Standard Resistance:

Text in Illustration

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

5. REPLACE TURN SIGNAL FLASHER ASSEMBLY

(a) Temporarily replace the turn signal flasher assembly with a new or known good one Components.

(b) Check that the turn signal lights flash.

OK:

Turn signal lights flash.

NG -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Exterior Lighting System

OK -- END

6. PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Body No. 3 / Active Test.

(e) Check that the turn signal lights LH.

Body No. 3 (Main Body ECU LH)

OK:

Turn signal lights flash.

NG -- CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - BODY GROUND)

OK -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Exterior Lighting System

7. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - BODY GROUND)

(a) Disconnect the LA main body ECU LH connector.

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

Standard Voltage:

Text in Illustration

NG -- CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - TURN SIGNAL FLASHER ASSEMBLY)
OK -- Continue to next step.

8. CHECK HARNESS AND CONNECTOR (TURN SIGNAL FLASHER ASSEMBLY - HEADLIGHT)

(a) Disconnect the J30 flasher assembly connector.

(b) Disconnect the B12 headlight assembly connector.

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

Standard Resistance:

Text in Illustration

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

9. REPLACE TURN SIGNAL FLASHER ASSEMBLY

(a) Temporarily replace the turn signal flasher assembly with a new or known good one Components.

(b) Check that the turn signal lights flash.

OK:

Turn signal lights flash.

NG -- REPLACE MAIN BODY ECU LH (COWL SIDE JUNCTION BLOCK LH)

OK -- END

10. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - TURN SIGNAL FLASHER ASSEMBLY)

(a) Disconnect the LA main body ECU LH connector.

(b) Disconnect the J30 flasher connector.

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

Standard Resistance:

Text in Illustration

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE TURN SIGNAL FLASHER ASSEMBLY Components

11. PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Body No. 3 / Active Test.

(e) Check that the turn signal lights RH operate.

Body No. 3 (Main Body ECU LH)

OK:

Turn signal lights flash.

NG -- CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - BODY GROUND)

OK -- PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Exterior Lighting System

12. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - BODY GROUND)

(a) Disconnect the LA main body ECU LH connector.

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

Standard Voltage:

Text in Illustration

NG -- CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - TURN SIGNAL FLASHER ASSEMBLY)
OK -- Continue to next step.

13. CHECK HARNESS AND CONNECTOR (TURN SIGNAL FLASHER ASSEMBLY - HEADLIGHT)

(a) Disconnect the J30 turn signal flasher assembly connector.

(b) Disconnect the B2 headlight assembly connector.

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

Standard Resistance:

Text in Illustration

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

14. REPLACE TURN SIGNAL FLASHER ASSEMBLY

(a) Temporarily replace the turn signal flasher assembly with a new or known good one Components.

(b) Check that the turn signal lights flash.

OK:

Turn signal lights flash.

NG -- REPLACE MAIN BODY ECU LH (COWL SIDE JUNCTION BLOCK LH)

OK -- END

15. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU LH - TURN SIGNAL FLASHER ASSEMBLY)

(a) Disconnect the LA main body ECU LH connector.

(b) Disconnect the J30 turn signal flasher assembly connector.

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

Standard Resistance:

Text in Illustration

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE TURN SIGNAL FLASHER ASSEMBLY Components