B1026

DTC Troubleshooting: B1026

DTC B1026: Front Passenger's Door Lock Switch Input 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. Operate the front passenger's door lock switch several times.

4. Check for DTCs with the HDS.

Is DTC B1026 indicated?
YES - Go to step 5.

NO - Intermittent failure, the system is OK at this time. Check for loose or poor connections.


5. With the front passenger's door lock switch in the neutral position, select SECURITY from BODY ELECTRICAL system select menu with the HDS, and enter the DATA LIST.

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

Are both information indicators OFF?
YES - Go to step 7.

NO - Go to step 12.


7. Push the front passenger's door lock switch to the LOCK and UNLOCK positions, and check the ON/OFF information of the FRONT PASSENGER'S DOOR LOCK SWITCH (LOCK) and FRONT PASSENGER'S DOOR LOCK SWITCH (UNLOCK) in the DATA LIST.

Are both FRONT PASSENGER'S DOOR LOCK SWITCH (LOCK) and FRONT PASSENGER'S DOOR LOCK SWITCH (UNLOCK) information indicate ON when the door lock switch is pushed in each switch position, and OFF when the door lock switch is released?
YES - Faulty MICU, replace the under-dash fuse/relay box.

NO - Go to step 8.


8. Remove the front passenger's door panel. Service and Repair

9. Disconnect the 10P connector from the front passenger's window/door lock switch.

10. Disconnect the 30P connector from under-dash fuse/relay box connector P.

11. Check for continuity between terminals No. 1 and No. 2 of the front passenger's window/door lock switch 10P connector.

Is there continuity?
YES - Repair a short in the wire.

NO - Replace the front passenger's door lock switch.






12. Remove the front passenger's door panel. Service and Repair

13. Disconnect the 10P connector from the front passenger's window/door lock switch.

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

Are both information indicators OFF?
YES - Replace the front passenger's door lock switch.

NO - Go to step 15.


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

16. Check for continuity between terminals No. 1 (UNLOCK) and No. 2 (LOCK) of the front passenger's window/door lock switch 10P connector and body ground.

Is there continuity?
YES - Repair a short to ground in the wire.

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