B1275
DTC B1275: Combination Light Switch OFF Position Circuit MalfunctionDTC B1276: Combination Light Switch Parking (SMALL) Position Circuit Malfunction
DTC B1278: Headlight Switch ON Position Circuit Malfunction
NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A.
1. Clear the DTCs with the HDS.
2. Turn the ignition switch OFF, and then back ON (II).
3. Turn the combination light switch to the park position, headlight position, then back to the off position.
4. Clear the DTCs with the HDS.
Is DTC B1275, B1276 or B1278 indicated?
YES - Go to step 5.
NO - Intermittent failure. The lighting system is OK at this time. Check for loose or poor connections.
5. Select LIGHTING from the BODY ELECTRICAL menu, and enter the DATA LIST.
6. Check the ON/OFF information of the HEADLIGHT SWITCH (OFF), HEADLIGHT SWITCH (PARKING) and HEADLIGHT SWITCH (HEADLIGHT).
Are the HEADLIGHT SWITCH (OFF) information indicator ON, HEADLIGHT SWITCH (PARKING) information indicator OFF and HEADLIGHT SWITCH (HEADLIGHT) information indicator OFF with the combination light switch in OFF position, and are the HEADLIGHT SWITCH (OFF) information indicator OFF, HEADLIGHT SWITCH (PARKING) information indicator ON and HEADLIGHT SWITCH (HEADLIGHT) information indicator OFF with the combination light switch in SMALL position, and are the HEADLIGHT SWITCH (OFF) information indicator OFF, HEADLIGHT SWITCH (PARKING) information indicator OFF and HEADLIGHT SWITCH (HEADLIGHT) information indicator ON with the combination light switch in ON position?
YES - Check for loose or poor connections connector. If all the connector tests prove OK, replace the under-dash fuse/relay box.
NO - Go to step 7.
7. Disconnect the 12P connector from the combination light switch.
8. Check the ON/OFF information of the HEADLIGHT SWITCH (OFF), HEADLIGHT SWITCH (PARKING) and HEADLIGHT SWITCH (HEADLIGHT) in the DATA LIST.
All the information indicators OFF?
YES - Go to step 12.
NO - Go to step 9.
9. Turn the ignition switch OFF.
10. Disconnect the under-dash fuse/relay box connector S (20P).
11. Check the continuity between the body ground and under-dash fuse/relay box connector S (20P) terminals No. 1, No. 11, and No. 13 individually.
Is there continuity?
YES - Repair a short to ground in the wire.
NO - Faulty MICU; replace the under-dash fuse/relay box.
12. Turn the ignition switch OFF.
13. Check the combination light switch.
Is the combination light switch OK?
YES - Go to step 14.
NO - Faulty combination light switch; replace it.
14. Disconnect the under-dash fuse/relay box connectors S (20P).
15. Check for continuity between the under-dash fuse/relay box connector S (20P) No. 1, No. 5, No. 11, and No. 13 terminals and the combination light switch 12P connector No. 9, No. 12, No. 10, and No. 11 terminals.
Is there continuity?
YES - Faulty MICU; replace the under-dash fuse/relay box.
NO - Repair an open in the wire.