DTC Troubleshooting
DTC Troubleshooting: P1673 (22)
DTC P1673:
Motor Control Module (MCM) Relay Stays Activated
NOTE:
- Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information Initial Inspection and Diagnostic Overview.
- If the DTC cannot be cleared, do the troubleshooting for DTC U1204.
1. Turn the ignition switch to ON (II).
2. Clear the DTC with the HDS.
3. Turn the ignition switch to LOCK (0), and wait at least 40 seconds. Turn the ignition switch to ON (II) again.
4. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P1673 indicated?
YES -
Go to step 5.
NO -
Intermittent failure, the system is OK at this time.
5. Turn the ignition switch to LOCK (0).
6. Turn the battery module switch OFF.
7. Remove the IPU cover IPU Cover Removal/Installation.
8. Remove MCM relay 1 (A).
9. Measure the voltage between MCM relay 1 4P connector terminals No. 3 and No. 4.
When you turn the ignition switch from ON (II) to LOCK (0), does the voltage change from 10 V or more down to 0 V?
YES -
Go to step 10.
NO -
Go to step 11.
10. Test MCM relay 1.
Is the relay OK?
YES -
Repair a short to power in the wire between MCM relay 1 and the MCM (A1), then go to step 14.
NO -
Replace MCM relay 1, then go to step 14.
11. Remove the PCU lid, the PCU busplate, and the PCU cover Service and Repair.
12. Disconnect MCM connector A (31P).
13. Check for continuity between body ground and MCM connector terminal A7.
Is there continuity?
YES -
Repair a short to ground in the wire between MCM relay 1 and the MCM (A7), then go to step 14.
NO -
Go to step 22.
14. Reconnect all connectors.
15. If removed, reinstall the PCU cover, the PCU busplate, and the PCU lid Service and Repair.
16. If removed, reinstall the IPU cover IPU Cover Removal/Installation, then turn the battery module switch ON.
17. Turn the ignition switch to ON (II).
18. Clear the DTC with the HDS.
19. Turn the ignition switch to LOCK (0), and wait at least 40 seconds. Turn the ignition switch to ON (II) again.
20. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P1673 indicated?
YES -
Go to step 1.
NO -
Go to step 21.
21. Monitor the OBD STATUS for DTC P1673 in the DTCs MENU with the HDS.
Does the HDS indicate PASSED?
YES -
Troubleshooting is complete. If any other Pending or Confirmed DTCs were indicated in step 20, go to the indicated DTC's troubleshooting.
NO -
If the HDS indicates FAILED, go to step 1. If the HDS indicates NOT COMPLETED, go to step 19.
22. Reconnect all connectors.
23. Reinstall the PCU cover, the PCU busplate, and the PCU lid Service and Repair.
24. Reinstall the IPU cover IPU Cover Removal/Installation, then turn the battery module switch ON.
25. Update the MCM if it does not have the latest software Testing and Inspection, or substitute a known-good MCM.
26. Turn the ignition switch to ON (II), and then to LOCK (0), then wait at least 40 seconds. Turn the ignition switch to ON (II) again.
27. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P1673 indicated?
YES -
If the MCM was updated, substitute a known-good MCM, and recheck. If the MCM was substituted, go to step 1.
NO -
Go to step 28.
28. Monitor the OBD STATUS for DTC P1673 in the DTCs MENU with the HDS.
Does the HDS indicate PASSED?
YES -
If the MCM was updated, troubleshooting is complete. If the MCM was substituted, replace the original MCM Service and Repair. If any other Pending or Confirmed DTCs were indicated in step 27, go to the indicated DTC's troubleshooting.
NO -
- If the HDS indicates FAILED: If the MCM was updated, substitute the MCM, and recheck. If the MCM was substituted, go to step 1.
- If the HDS indicates NOT COMPLETED: Go to step 26.