DTC Troubleshooting

DTC P0A27 (46): High Voltage Contactor/Bypass Contactor Stays Activated

NOTE: Before you troubleshoot, record all freeze data, and review the general troubleshooting information.

1. Turn the ignition switch OFF, and wait 30 seconds.
2. Turn the ignition switch ON (II).
3. Monitor the OBD STATUS for DTC POA27 (46) in the DTCs MENU with the HDS.

Does the screen indicate FAILED?

YES - Go to step 4.

NO - If the screen indicates PASSED, intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the high voltage contactor, the bypass contactor, the MCM, and the BCM module. If the screen indicates NOT COMPLETED, go to step 1.

4. Turn the ignition switch OFF.
5. Turn the battery module switch OFF.
6. Remove the IPU lid.
7. Turn the ignition switch ON (II), and then OFF. Wait 1 minute, then measure voltage between body ground and BCM module connector terminals A13 and A14 individually.






Is there 12 V battery voltage on either terminal?

YES - Go to step 19.

NO - Go to step 8.

8. Remove the battery module.
9. Measure resistance between high voltage contactor terminals No. 1 (A) and No. 2 (B).






Is there about 0 ohms?

YES - Replace the battery module, then go to step 11.

NO - Go to step 10.

10. Measure resistance between high voltage contactor terminals No. 1 (A) and No. 2 (B).






Is there 38 - 42 ohms?

YES - Replace the battery module, then go to step 11.

NO - Go to step 27.

11. Reconnect all connectors.
12. Reinstall the IPU lid, and turn the battery module switch ON.
13. Turn the ignition switch ON (II).
14. Clear the DTC with the HDS.
15. Turn the ignition switch OFF, and wait 30 seconds.
16. Turn the ignition switch ON (II).
17. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P0A27 (46) indicated?

YES - Check for poor connections or loose terminals at the high voltage contactor, the bypass contactor, the MCM, and the BCM module, then go to step 1.

NO - Go to step 18.

18. Monitor the OBD STATUS for DTC POA27 (46) in the DTCs MENU with the HDS.

Does the screen indicate PASSED?

YES - Troubleshooting is complete. If any other Temporary DTCs or DTCs were indicated in step 17, go to the indicated DTC's troubleshooting.

NO - If the screen indicates FAILED, check for poor connections or loose terminals at the high voltage contactor, the bypass contactor, the MCM, and the BCM module, then go to step 1. If the screen indicates NOT COMPLETED, go to step 15.

19. Turn the ignition switch OFF.
20. Reinstall the IPU lid, then turn the battery module switch ON.
21. Update the BCM module if it does not have the latest software, or substitute a known-good BCM module.
22. Clear the DTC with the HDS.
23. Turn the ignition switch OFF, and wait 30 seconds.
24. Turn the ignition switch ON (II).
25. Check for Temporary DTCs or DTCs with the HDS.

Is DTC POA27 (46) indicated?

YES - Check for poor connections or loose terminals at the high voltage contactor, the bypass contactor, the MCM, and the BCM module. If the BCM module was updated, substitute a known-good BCM module, then go to step 23. If the BCM module was substituted, go to step 1.

NO - Go to step 26.

26. Monitor the OBD STATUS for DTC POA27 (46) in the DTCs MENU with the HDS.

Does the screen indicate PASSED?

YES - If the BCM module was updated, troubleshooting is complete. If the BCM module was substituted, replace the original BCM module. If any other Temporary DTCs or DTCs were indicated in step 25, go to the indicated DTC's troubleshooting.

NO - If the screen indicates FAILED, check for poor connections or loose terminals at the high voltage contactor, the bypass contactor, the MCM, and the BCM module, then go to step 1. If the screen indicates NOT COMPLETED, go to step 23.

27. Reinstall the IPU lid, then turn the battery module switch ON.
28. Update the MCM if it does not have the latest software, or substitute a known-good MCM.
29. Clear the DTC with the HDS.
30. Turn the ignition switch OFF, and wait 30 seconds.
31. Turn the ignition switch ON (II).
32. Check for Temporary DTCs or DTCs with the HDS.

Is DTC POA27 (46) indicated?

YES - Check for poor connections or loose terminals at the high voltage contactor, the bypass contactor, the MCM, and the BCM module. If the MCM was updated, substitute a known-good MCM, then go to step 30. If the MCM was substituted, go to step 1.

NO - Go to step 33.

33. Monitor the OBD STATUS for DTC POA27 (46) 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. If any other Temporary DTCs or DTCs were indicated in step 32, go to the indicated DTC's troubleshooting.

NO - If the screen indicates FAILED, check for poor connections or loose terminals at the high voltage contactor, the bypass contactor, the MCM, and the BCM module, then go to step 1. If the screen indicates NOT COMPLETED, go to step 30.