Turn Signal Light Circuit

LIGHTING: LIGHTING SYSTEM: Turn Signal Light Circuit
- Turn Signal Light Circuit

DESCRIPTION

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

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 the bulb, or the circuit between the bulb and body ground.

Result:

C -- PERFORM ACTIVE TEST USING TECHSTREAM

B -- 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 the operation.

Body No. 3 (Main Body ECU LH)

Body No. 3 (Main Body ECU LH):

OK:

Turn signal lights flash.

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

OK -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

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

(a) Remove the LH-IG fuse from the cowl side J/B LH.

(b) Remove the TURN-HAZ fuse from the engine room No. 1 J/B.

(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 connector.

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

Standard resistance:

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

5. REPLACE TURN SIGNAL FLASHER

(a) Temporarily replace the turn signal flasher with a new or normally functioning one.

(b) Check that the turn signal lights flash.

OK:

Turn signal lights flash.

NG -- PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

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 the operation.

Body No. 3 (Main Body ECU 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 CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

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:

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

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

(a) Disconnect the J30 flasher connector.

(b) Disconnect the B12 headlight connector.

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

Standard resistance:

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

9. REPLACE TURN SIGNAL FLASHER

(a) Temporarily replace the turn signal flasher with a new or normally functioning one.

(b) Check that the turn signal lights flash.

OK:

Turn signal lights flash.

NG -- REPLACE MAIN BODY ECU LH (COWL SIDE J/B LH)

OK -- END

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

(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:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE TURN SIGNAL FLASHER

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 the operation.

Body No. 3 (Main Body ECU 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 CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

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:

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

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

(a) Disconnect the J30 flasher connector.

(b) Disconnect the B2 headlight connector.

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

Standard resistance:

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

14. REPLACE TURN SIGNAL FLASHER

(a) Temporarily replace the turn signal flasher with a new or normally functioning one.

(b) Check that the turn signal lights flash.

OK:

Turn signal lights flash.

NG -- REPLACE MAIN BODY ECU LH (COWL SIDE J/B LH)

OK -- END

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

(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:

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR

OK -- REPLACE TURN SIGNAL FLASHER