The VTM-4 Lock Indicator Does Not Come On When The VTM-4 Lock Button Is Pressed

Rear Differential Symptom Troubleshooting - The VTM-4 LOCK indicator does not come on when the VTM-4 LOCK button is pressed

The VTM-4 LOCK indicator does not come on when the VTM-4 LOCK button is pressed

NOTE:

- Before you troubleshoot, review the general troubleshooting information Initial Inspection and Diagnostic Overview.
- The VTM-4 LOCK indicator will only come on when the engine is running and the transmission is in R, 1, or 2 before the VTM-4 LOCK button is pressed.

1. Check the No. 21 (7.5 A) fuse in the under-dash fuse/relay box.

Is the fuse OK?

YES -

Go to step 2.

NO -

Replace the fuse, and recheck.�

2. Turn the ignition switch to ON (II).

3. Check the VTM-4 LOCK indicator.

Does the VTM-4 LOCK indicator come on, and does it go off about 4 seconds later?

YES -

Go to step 4.

NO -

Go to step 11.

4. Start the engine, and move the shift lever to R, 1, and 2, then Check the VTM-4 LOCK indicator.

Does the VTM-4 LOCK indicator come on when the VTM-4 LOCK button is pressed?

YES -

Intermittent failure, the system is OK at this time.�

NO -

Go to step 5.

5. Check for DTCs in the A/T system with the HDS.

Are there any A/T system DTC's indicated?

YES -

Go to the indicated DTC's troubleshooting.�

NO -

Go to step 6.

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

7. Disconnect VTM-4 control unit connector A (22P).

8. Turn the ignition switch to ON (II).

9. Measure the voltage between VTM-4 control unit connector terminal A8 and body ground.





Is there battery voltage when the VTM-4 LOCK button is pressed?

YES -

Check for poor connections or loose terminals at the VTM-4 control unit connectors. If the connections are OK, substitute a known-good VTM-4 control unit Service and Repair and recheck. If the symptom/indication goes away with the known-good VTM-4 control unit, replace the original VTM-4 control unit Service and Repair.�

NO -

Go to step 10.

10. Test the VTM-4 LOCK switch Service and Repair.

Is the VTM-4 LOCK switch OK?

YES -

Repair an open in the wire between the VTM-4 LOCK switch and the VTM-4 control unit.�

NO -

Replace the VTM-4 LOCK switch Service and Repair.�

11. Connect VTM-4 control unit connector terminal A16 to body ground with a jumper wire.






12. Check the VTM-4 LOCK indicator.

Does the VTM-4 LOCK indicator come on?

YES -

Check for poor connections or loose terminals at the VTM-4 control unit connectors. If the connections are OK, substitute a known-good VTM-4 control unit Service and Repair and recheck. If the symptom/indication goes away with the known-good VTM-4 control unit, replace the original VTM-4 control unit Service and Repair.�

NO -

Go to step 13.

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

14. Remove the jumper wire from VTM-4 control unit connector terminal A16.

15. Remove the VTM-4 LOCK switch Service and Repair.

16. Connect the VTM-4 LOCK switch 5P connector terminal No. 5 to body ground with a jumper wire.






17. Check the continuity between VTM-4 control unit connector terminal A16 and body ground.





Is there continuity?

YES -

Go to step 18.

NO -

Repair an open in the wire between VTM-4 control unit connector terminal A16 and the VTM-4 LOCK switch.�

18. Remove the jumper wire from the VTM-4 LOCK switch.

19. Turn the ignition switch to ON (II).

20. Measure the voltage between the VTM-4 LOCK switch 5P connector terminal No. 2 and body ground.





Is there battery voltage?

YES -

Replace the VTM-4 LOCK indicator bulb Service and Repair.�

NO -

Repair an open in the wire between the VTM-4 LOCK switch 5P connector terminal No. 2 and the under-dash fuse/relay box.�