DTC Troubleshooting
DTC Troubleshooting: P1437 (41)
DTC P1437 (41):
MCM Circuit Shorted
NOTE:
- Before you troubleshoot, record all freeze data, and review the general troubleshooting information Initial Inspection and Diagnostic Overview.
- Information marked with an asterisk (*) applies to the '06-07 models.
1. Turn the ignition switch to ON (II).
2. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0AA6 (59), P1440 (57), or P15A5 (85) indicated?
YES -
Go to the indicated DTC's troubleshooting.�
NO -
Go to step 3.
3. Clear the DTC with the HDS.
4. Turn the ignition switch to LOCK (0), and wait 1 minute.
5. Start the engine, and let it idle.
6. Monitor the OBD STATUS for DTC P1437 (41) in the DTCs MENU with the HDS.
Does the screen indicate FAILED?
YES -
Go to step 7.
NO -
If the screen indicates PASSED, intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the MCM. If the screen indicates NOT COMPLETED, go to step 1.
7. Turn the ignition switch to LOCK (0).
8. Turn the battery module switch OFF.
9. Remove the IPU lid IPU Lid Removal/Installation.
10. Remove the BCM module Service and Repair.
11. Disconnect the MCM 20P connector.
12. Connect the BCM module connectors.
13. Turn the ignition switch to ON (II), then measure the voltage between MCM 20P connector terminal No. 18,No. 19* and body ground within 1 second.
Is there battery voltage on terminals?
YES -
Go to step 23.
NO -
- Repair the connection in the MCM connector, then go to step 14.
- Repair open or short in the wire between the No. 61 +B IMA 2 (10 A) fuse, MCM relay 2, and the MCM, then go to step 14.
14. Turn the ignition switch to LOCK (0).
15. Reconnect all connectors.
16. Reinstall the IPU lid IPU Lid Removal/Installation, then turn the battery module switch ON High Voltage Safety.
17. Turn the ignition switch to ON (II).
18. Clear the DTC with the HDS Initial Inspection and Diagnostic Overview.
19. Turn the ignition switch to LOCK (0), and wait 1 minute.
20. Start the engine, and let it idle.
21. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P1437 (41) indicated?
YES -
Check for poor connections or loose terminals at the MCM, then go to step 1.
NO -
Go to step 22.
22. Monitor the OBD STATUS for DTC P1437 (41) in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES -
Troubleshooting is complete. If any other Pending or Confirmed DTCs were indicated in step 21, go to the indicated DTC's troubleshooting.�
NO -
If the screen indicates FAILED, check for poor connections or loose terminals at the DC-DC converter and the MCM, then go to step 1. If the screen indicates NOT COMPLETED, keep the ignition switch ON (II) until a result comes on.
23. Turn the ignition switch to LOCK (0).
24. Reconnect all connectors.
25. Reinstall the IPU lid IPU Lid Removal/Installation, then turn the battery module switch ON High Voltage Safety.
26. Update the MCM if it does not have the latest software Testing and Inspection, or substitute a known-good MCM Initial Inspection and Diagnostic Overview.
27. Turn the ignition switch to LOCK (0), and wait 1 minute.
28. Start the engine, and let it idle.
29. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P1437 (41) indicated?
YES -
Check for poor connections or loose terminals at DC-DC converter and the MCM. If the MCM was updated, substitute a known-good MCM Initial Inspection and Diagnostic Overview, then recheck. If the MCM was substituted, go to step 1.
NO -
Go to step 30.
30. Monitor the OBD STATUS for DTC P1437 (41) in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES -
If the MCM was updated, troubleshooting is complete. If the MCM was substituted, replace the original MCM MCM Replacement. If any other Pending or Confirmed DTCs were indicated in step 29, go to the indicated DTC's troubleshooting.�
NO -
If the screen indicates FAILED, check for poor connections or loose terminals at DC-DC converter and the MCM. If the MCM was updated, substitute a known-good MCM Initial Inspection and Diagnostic Overview, then recheck. If the MCM was substituted, go to step 1. If the screen indicates NOT COMPLETED, keep the ignition switch ON (II) until a result comes on.