76-1

VTM-4 DTC Troubleshooting: 76-1

DTC 76-1:

Rear Differential Clutch Warning System

NOTE: Before you troubleshoot, review the general troubleshooting information Initial Inspection and Diagnostic Overview.

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

2. Clear the DTC with the HDS.

3. Test-drive the vehicle at 25 mph (40 km/h) or more, while keeping the engine speed below 2,500 rpm for at least 30 seconds.

NOTE: Be careful not to overheat the rear differential clutch system.

4. Check for DTCs with the HDS.

Is DTC 76-1 indicated?

YES -

Go to step 5.

NO -

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

5. Check for DTCs in the VSA system with the HDS.

Are there any VSA DTCs indicated?

YES -

Go to the indicated DTC's troubleshooting.�

NO -

Go to step 6.

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

7. Raise and support the vehicle Service and Repair.

8. Spin the rear wheels by hand, and check for rear brake drag.

Are the rear brakes dragging?

YES -

Repair cause of rear brake drag, and retest.�

NO -

Go to step 9.

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

10. Measure the voltage between body ground and the appropriate VTM-4 control unit connector terminal (see table) while rotating the appropriate wheel (1 rotation/second).









Is there about 2.0 to 3.0 V?

YES -

Go to step 11.

NO -

Go to step 13.

11. Test-drive the vehicle at 25 mph (40 km/h) or more, while keeping the engine speed below 2,500 rpm for at least 30 seconds.

NOTE: Be careful not to overheat the rear differential clutch system.

12. Check for DTCs with the HDS.

Is DTC 76-1 indicated?

YES -

Replace the VSA modulator-control unit Service and Repair.�

NO -

Troubleshooting is complete. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.�

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

14. Disconnect the VTM-4 control unit and the VSA modulator-control unit connectors.

15. Check for continuity between VTM-4 control unit connector terminals A3 and A5 to body ground respectively.





Is there continuity?

YES -

Repair a short to body ground in the wire between VTM-4 control unit (A3 and/or A5) and the VSA modulator-control unit.�

NO -

Go to step 16.

16. Connect body ground and the appropriate VTM-4 control unit connector terminals A3 and A5 to body ground with the jumper wires (see table).










17. Check for continuity between body ground and the appropriate VSA modulator-control unit 46P connector terminal (see table).









Is there continuity?

YES -

Check for poor connections or loose terminals at the VTM-4 control unit and the VSA modulator-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 -

Repair an open in the wire between VTM-4 control unit (A3 and/or A5) and the VSA modulator-control unit.�