DTC Troubleshooting
DTC Troubleshooting: P0A27 (46)
DTC P0A27 (46):
High Voltage Contactor/Bypass Contactor 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 (55).
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 30 seconds.
4. Turn the ignition switch to ON (II).
5. Monitor the OBD STATUS for DTC P0A27 (46) in the DTCs MENU with the HDS.
Does the screen indicate FAILED?
YES -
Go to step 6.
NO -
If the screen indicates PASSED, intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the junction board and the MCM. If the screen indicates NOT COMPLETED, go to step 1.
6. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P1634 (47) indicated?
YES -
Do the troubleshooting for DTC P1634 (47) P1634.
NO -
Go to step 7.
7. Turn the ignition switch to LOCK (0).
8. Turn the battery module switch OFF.
9. Remove the IPU cover IPU Cover Removal/Installation.
10. Remove the PCU lid, the PCU busplate, and the PCU cover Service and Repair.
11. Turn the battery module switch ON.
12. Turn the ignition switch to ON (II), and then turn it to LOCK (0). Wait 1 minute, then measure the voltage between these MCM connector terminals individually:
- B6 and B15
- B14 and B15
Is there battery voltage between either of the terminals?
YES -
Go to step 24.
NO -
Replace the battery module Service and Repair, then go to step 13.
13. Turn the battery module switch OFF.
14. Turn the ignition switch to LOCK (0).
15. Reconnect all connectors.
16. Reinstall the PCU cover, the PCU busplate, and the PCU lid Service and Repair.
17. Reinstall the IPU cover IPU Cover Removal/Installation, and turn the battery module switch ON.
18. Turn the ignition switch to ON (II).
19. Clear the DTC with the HDS.
20. Turn the ignition switch to LOCK (0), and wait 30 seconds.
21. Turn the ignition switch to ON (II).
22. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0A27 (46) indicated?
YES -
Check for poor connections or loose terminals at the junction board and the MCM, then go to step 1.
NO -
Go to step 23.
23. Monitor the OBD STATUS for DTC P0A27 (46) 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 22, go to the indicated DTC's troubleshooting.�
NO -
If the screen indicates FAILED, check for poor connections or loose terminals at the junction board and the MCM, then go to step 1. If the screen indicates NOT COMPLETED, go to step 20.
24. Reinstall the PCU cover, the PCU busplate, and the PCU lid Service and Repair.
25. Reinstall the IPU cover IPU Cover Removal/Installation, then turn the battery module switch ON.
26. Update the MCM if it does not have the latest software Testing and Inspection, or substitute a known-good MCM.
27. Turn the ignition switch to LOCK (0), and wait 30 seconds.
28. Turn the ignition switch to ON (II).
29. Check for Pending or Confirmed 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, and the MCM. 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 30.
30. Monitor the OBD STATUS for DTC P0A27 (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 Service and Repair. 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 the high voltage contactor, the bypass contactor, and the MCM. If the MCM was updated, substitute a known-good MCM, and recheck. If the MCM was substituted, go to step 1. If the screen indicates NOT COMPLETED, go to step 27.