DTC Troubleshooting: B1129

DTC B1129: Driver's Door Lock Knob Switch Signal Error

1. Clear the DTCs using the HDS.

1. Cycle the ignition switch to OFF, and then back ON.

1. Operate the driver's door lock knob switch.

1. Check the DTCs by selecting the DTCs MENU (DTCs) from the HDS.

Is DTC B1129 indicated?

YES | - | Go to Step 5 .
NO | - | Intermittent failure. The driver's door lock knob switch system is OK at this time.■

1. With no driver's door lock knob switch operation, select the TEST MODE MENU from the HDS, and enter the DATA LIST.
   Check the ON/OFF information of the DRV DOR KNOB LK and DRV DOR KNOB UNLK in the DATA LIST.

Is the DRV DOR KNOB LK information indicator ON and DRV DOR KNOB UNLK information indicator OFF with the door lock knob switch in LOCK position, and is the DRV DOR KNOB LK information indicator OFF and DRV DOR KNOB UNLK information indicator ON with the door lock knob switch in UNLOCK position?

YES | - | Intermittent failure, the door multiplex control unit (power window master switch) is OK at this time.■
NO | - | Go to Step 6 .

1. Disconnect the driver's door lock knob switch 3P connector.

1. Check the ON/OFF information of the DRV DOR KNOB LK and DRV DOR KNOB UNLK in the DATA LIST.

Are both information indicators OFF?

YES | - | Faulty driver's door lock knob switch.■
NO | - | Go to Step 8 .

1. Check for continuity between the No. 2 (LOCK) and No. 1 (UNLOCK) terminals of the driver's door lock knob switch 3P connector and body ground.

Is there continuity?

YES | - | Repair a short in the YEL/RED (LOCK) or WHT/BLK (UNLOCK) wire.■
NO | - | Go to driver's door lock knob switch test . If the driver's door lock knob switch is OK; faulty door multiplex control unit; replace the power window master switch.■