DTC Troubleshooting: B1128

DTC B1128:  Driver's Door Lock Switch Signal Error

1.Clear the DTCs with the HDS.

2.Turn the ignition switch OFF, and then back ON (II).

3.Operate the driver's door lock switch LOCK/UNLOCK ten times.

4.Check for DTCs with the HDS.

Is DTC B1128 indicated?


YES - Go to 5.


NO - Intermittent failure. The driver's door lock system is OK at this time.n


5.With the driver's door lock switch in the neutral position, select KEYLESS from the HDS and enter the DATA LIST.

6.Check the ON/OFF information of the DRIVER'S DOOR LOCK SWITCH (LOCK) and DRIVER'S DOOR LOCK SWITCH (UNLOCK) in the DATA LIST.

Are both information indicators OFF?


YES - Faulty MICU, replace the under-dash fuse/relay box.n


NO - Go to 7.


7.Disconnect the driver's power window switch 22P connector.

8.Check the ON/OFF information of the DRIVER'S DOOR LOCK SWITCH (LOCK) and DRIVER'S DOOR LOCK SWITCH (UNLOCK) in the DATA LIST.

Are both information indicators OFF?


YES - Faulty door lock switch; replace the driver's power window switch.n


NO - Go to 9.


9.Turn the ignition switch OFF.

10.Disconnect the under-dash fuse/relay box connector T (34P).

11.Check for continuity between the No. 28 (LOCK) and No. 27 (UNLOCK) terminals of the under-dash fuse/relay box connector T (34P) and body ground.

 

Are there continuity?


YES - Repair a short in the LOCK or UNLOCK wire.n


NO - Go to 12.


12.Check for continuity between the No. 28 (LOCK) and No. 27 (UNLOCK) terminals of the under-dash fuse/relay box connector T (34P).

 

Is there continuity?


YES - Repair a short in the wire between the LOCK and UNLOCK wires.n


NO - Faulty MICU, replace the under-dash fuse/relay box.n