Turn Signal Light Circuit

LIGHTING: LIGHTING SYSTEM: Turn Signal Light Circuit

Turn Signal Light Circuit

DESCRIPTION

The turn signal flasher relay in the main body ECU turns on when it receives signals from the headlight dimmer switch integrated with the turn signal switch, causing the turn signal lights to flash.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK OPERATION OF TURN SIGNAL LIGHT
(a) When the turn signal light switch is operated, check that the appropriate turn signal light flashes.
Result:






D -- INSPECT BULB (REAR TURN SIGNAL LIGHT BULB)
C -- INSPECT BULB (SIDE TURN SIGNAL LIGHT BULB)
B -- INSPECT BULB (FRONT TURN SIGNAL LIGHT BULB)
A -- Continue to next step.
2. INSPECT FUSE (GAUGE, HAZ)
(a) Remove the GAUGE fuse from the main body ECU.
(b) Remove the HAZ fuse from the engine room relay block.
(c) Measure the resistance.
Standard resistance:
Below 1 Ohms
(d) Reinstall the GAUGE and HAZ fuses.
NG -- REPLACE FUSE
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (FUSE - MAIN BODY ECU)




(a) Disconnect the 4B main body ECU connector.
(b) Measure the voltage.
Standard voltage:





(c) Reconnect the main body ECU connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
4. INSPECT HEADLIGHT DIMMER SWITCH




(a) Remove the headlight dimmer switch.
(b) Inspect the turn signal switch.
(c) Measure the resistance.
Standard resistance:





(d) Reinstall the headlight dimmer switch.
NG -- REPLACE HEADLIGHT DIMMER SWITCH
OK -- Continue to next step.
5. CHECK HARNESS AND CONNECTOR (HEADLIGHT DIMMER SWITCH - MAIN BODY ECU)




(a) Disconnect the D4 headlight dimmer switch connector.
(b) Disconnect the 4S and 4E and main body ECU connectors.
(c) Measure the resistance.
Standard resistance:





(d) Reconnect the headlight dimmer switch connector.
(e) Reconnect the main body ECU connectors.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE MAIN BODY ECU
6. INSPECT BULB (FRONT TURN SIGNAL LIGHT BULB)




(a) Hatchback:
(1) Remove the front turn signal light.
(2) Apply battery voltage to the terminals and check that the front turn signal light illuminates.
(3) Reinstall the front turn signal light.
Standard:









(b) Sedan:
(1) Remove the front turn signal light.
(2) Apply battery voltage to the terminals and check that the front turn signal light illuminates.
(3) Reinstall the front turn signal light.
Standard:






NG -- REPLACE BULB
OK -- Continue to next step.
7. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - FRONT TURN SIGNAL LIGHT)




(a) Hatchback:
(1) Disconnect the B1 and B8 front turn signal light connectors.
(2) Disconnect the 4B main body ECU connector.
(3) Measure the resistance.
Standard resistance:






(4) Reconnect the front turn signal light connectors.
(5) Reconnect the main body ECU connector.




(b) Sedan:
(1) Disconnect the B14 and B15 front turn signal light (Headlight assembly) connectors.
(2) Disconnect the 4B main body ECU connector.
(3) Measure the resistance.
Standard resistance:






(4) Reconnect the front turn signal light connectors.
(5) Reconnect the main body ECU connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR (FRONT TURN SIGNAL LIGHT - BODY GROUND)
8. INSPECT BULB (SIDE TURN SIGNAL LIGHT BULB)
(a) Remove the side turn signal light assembly.




(b) Apply battery voltage to the terminals and check that the side turn signal light illuminates.
Standard:





(c) Reinstall the side turn signal light assembly.
NG -- REPLACE BULB
OK -- Continue to next step.
9. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - SIDE TURN SIGNAL LIGHT ASSEMBLY)




(a) Disconnect the A1 and A2 side turn signal light assembly connectors.
(b) Disconnect the 4B main body ECU connector.
(c) Measure the resistance.
Standard resistance:





(d) Reconnect the side turn signal light assembly connectors.
(e) Reconnect the main body ECU connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR (SIDE TURN SIGNAL LIGHT ASSEMBLY - BODY GROUND)
10. INSPECT BULB (REAR TURN SIGNAL LIGHT BULB)




(a) Hatchback:
(1) Remove the rear combination light assembly.
(2) Apply battery voltage to the terminals and check that the rear turn signal light illuminates.
Standard:






(3) Reinstall the rear combination light assembly.




(b) Sedan:
(1) Remove the rear combination light assembly.
(2) Apply battery voltage to the terminals and check that the rear turn signal light illuminates.
Standard:






(3) Reinstall the rear combination light assembly.
NG -- REPLACE BULB
OK -- Continue to next step.
11. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - REAR TURN SIGNAL LIGHT)




(a) Hatchback:
(1) Disconnect the J3 and J4 rear combination light assembly connectors.
(2) Disconnect the 4A main body ECU connector.
(3) Measure the resistance.
Standard resistance:






(4) Reconnect the rear combination light assembly connectors.
(5) Reconnect the main body ECU connector.




(b) Sedan:
(1) Disconnect the J34 and J35 rear combination light assembly connectors.
(2) Disconnect the 4A main body ECU connector.
(3) Measure the resistance.
Standard resistance:






(4) Reconnect the rear combination light assembly connectors.
(5) Reconnect the main body ECU connector.
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR (REAR TURN SIGNAL LIGHT - BODY GROUND)