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The VTM-4 Indicator Comes on, But No DTCs Are Stored In Any System: VTM-4, VSA, or PCM




Symptom Troubleshooting: The VTM-4 indicator comes on, but no DTCs are stored in any system: VTM-4, VSA, or PCM

The VTM-4 indicator comes on, but no DTCs are stored in any system: VTM-4, VSA, or PCM

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

Is the fuse OK?
YES - Go to step 2.

NO - Replace the fuse, and recheck.


2. Reinitialize the VTM-4 control unit, Initial Inspection and Diagnostic Overview and watch the VTM-4 indicator.

Does the VTM-4 indicator come on and stay on?
YES - Go to step 3.

NO - The system is OK at this time.


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

4. Measure the voltage between VTM-4 control unit connector terminals A1 and A10, and between VTM-4 control unit connector terminals A1 and B12.

Is there battery voltage?
YES - Go to step 5.

NO - Repair open in the wire between VTM-4 control unit (A1) and the driver's under-dash fuse/relay box, or repair open in the wire between VTM-4 control unit (A10 or B12) and body ground, or check the poor ground (G501).






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

6. Disconnect the VTM-4 control unit and the gauge control module connectors.

7. Check for continuity between the VTM-4 control unit connector terminal A14, and VTM-4 control unit connector terminal B11 to body ground.

Is there continuity?
YES - Repair short to ground in the wire between VTM-4 control unit (A14 or B11) and the gauge control module.

NO - Go to step 8.






8. Reconnect the gauge control module connectors.

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

10. Watch the VTM-4 indicator.

Does the VTM-4 indicator come on?
YES - Replace the gauge control module. Service and Repair

NO - Check for poor connections or loose terminals at the VTM-4 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