44-1

VTM-4 DTC Troubleshooting: 44-1

DTC 44-1: VTM-4 Relay

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

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

2. Make sure the HDS communicates with the vehicle and the VTM-4 control unit. If it doesn't, troubleshoot the DLC circuit. Testing and Inspection

3. Clear the DTC with the HDS.

4. Test-drive the vehicle, and check for DTCs with the HDS.

Is DTC 44-1 indicated?
YES - Go to step 5.

NO - Intermittent failure, the system is OK at this time.


5. Measure the voltage between VTM-4 control unit connector terminal A4 and body ground, and between VTM-4 control unit connector terminal B7 and body ground with the ignition switch to ON (II), and after the engine starts.





Is the voltage correct?
YES - Go to step 17.

NO - Go to step 6.






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

7. Remove the VTM-4 relay, Service and Repair and test it. Power Relay Test

Is the VTM-4 relay OK?
YES - Go to step 8.

NO - Replace the VTM-4 relay. Service and Repair


8. Turn the ignition switch to ON (II) with the VTM-4 relay removed.

9. Measure the voltage between VTM-4 relay 5P connector terminals No. 1 and No. 5 to body ground.

Is there battery voltage?
YES - Go to step 10.

NO - Check for blown No. 4 (20 A) fuse in the auxiliary fuse box or No. 18 (15 A) fuse in the driver's under-dash fuse/relay box. If the fuses are OK, repair open in the wire between the auxiliary fuse box or the driver's under-dash fuse/relay box and the VTM-4 relay.






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

11. Disconnect the VTM-4 control unit connector A (22P) and connector B (12P).

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

13. Measure the voltage between VTM-4 control unit connector terminal A4 and body ground, and between VTM-4 control unit connector terminal B7 and body ground.

Is there battery voltage?
YES - Repair short to power in the wire between the VTM-4 control unit (A4 or B7) and the VTM-4 relay.

NO - Go to step 14.






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

15. Check for continuity between VTM-4 control unit connector terminal A4 and body ground, and between VTM-4 control unit connector terminal B7 and body ground.

Is there continuity?
YES - Repair short to ground in the wire between VTM-4 control unit (A4 or B7) and the VTM-4 relay.

NO - Go to step 16.






16. Check for continuity between VTM-4 control unit connector terminal A4 and the VTM-4 relay 5P connector terminal No. 2, and between VTM-4 control unit connector terminal B7 and the VTM-4 relay 5P connector terminal No. 3.

Is there continuity?
YES - Go to step 17.

NO - Repair open in the wire between VTM-4 control unit connector terminals A4 or B7 and the VTM-4 relay.






17. Check for poor connections or loose terminals at the VTM-4 control unit and the VTM-4 relay connectors. If the connections are OK, go to step 18.

18. Test-drive the vehicle, and check for DTCs with the HDS.

Is DTC 44-1 indicated?
YES - 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 - The system is OK at this time.