B1280

DTC Troubleshooting: B1280

DTC B1280:

Turn Signal Switch Circuit Malfunction

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A Troubleshooting - B-CAN System Diagnosis Test Mode A.

1. Clear the DTCs with the HDS.

2. Turn the ignition switch to LOCK (0) and then back to ON (II).

3. Move the turn signal switch to the left position and the right position.

4. Check the DTCs with the HDS.

Is DTC B1280 indicated?

YES -

Go to step 5.

NO -

Intermittent failure. The turn signal/hazard warning lights system is OK at this time. Check for loose or poor connections.

5. Select LIGHTING from the BODY ELECTRICAL SYSTEM SELECT menu, and enter DATA LIST.

6. Check the ON/OFF information of the TURN SIGNAL SWITCH (LEFT) and TURN SIGNAL SWITCH (RIGHT).

Are the TURN SIGNAL SWITCH (LEFT) information indicator ON, TURN SIGNAL SWITCH (RIGHT) information indicator OFF with the turn signal switch to the LEFT position, and are the TURN SIGNAL SWITCH (LEFT) information indicator OFF, TURN SIGNAL SWITCH (RIGHT) information indicator ON with the turn signal switch to the RIGHT position?

YES -

Faulty MICU; replace the under-dash fuse/relay box Under-Dash Fuse/Relay Box Removal and Installation.

NO -

Go to step 7.

7. Disconnect the 12P connector from the combination light switch.

8. Check the ON/OFF information of the TURN SIGNAL SWITCH (LEFT) and TURN SIGNAL SWITCH (RIGHT) in the DATA LIST.

Are the information indicators OFF?

YES -

Go to step 12.

NO -

Go to step 9.

9. Turn the ignition switch to LOCK (0).

10. Disconnect under-dash fuse/relay box connector S (20P).

11. Check for continuity between body ground and under-dash fuse/relay box connector S (20P) terminals No. 18 and No. 19 individually.





Is there continuity?

YES -

Check for continuity between terminal No. 5 and terminals No. 18, and No. 19 individually. If there is still continuity, repair a short to ground, or to another wire.

NO -

Faulty MICU; replace the under-dash fuse/relay box Under-Dash Fuse/Relay Box Removal and Installation.

12. Turn the ignition switch to LOCK (0).

13. Check the combination light switch Service and Repair.

Is the combination light switch OK?

YES -

Go to step 14.

NO -

Faulty combination light switch; replace it Service and Repair.

14. Disconnect under-dash fuse/relay box connector S (20P).

15. Check for continuity between under-dash fuse/relay box connector S (20P) terminals No. 5, No. 18, and No. 19 and the combination light switch 12P connector terminals No. 12, No. 1, and No. 2 respectively.





Is there continuity?

YES -

Go to step 16.

NO -

Repair an open or high resistance in the wire.

16. Check for continuity between under-dash fuse/relay box connector S (20P) terminals No. 5, No. 18, and between terminals No. 5 and No. 19 individually.





Is there continuity?

YES -

Repair a short in the wires.

NO -

Faulty MICU; replace the under-dash fuse/relay box Under-Dash Fuse/Relay Box Removal and Installation.