P0A27

DTC P0A27 (46): High Voltage Contactor/Bypass Contactor Stays Activated
1. Turn the ignition switch ON (II).
2. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P16C1 indicated?
YES - Do the troubleshooting for DTC P16C1.
NO - Go to step 3.

3. Reset the MCM.
4. Turn the ignition switch OFF, and wait 30 seconds.
5. Turn the ignition switch ON (II).
6. Check the SOC in the DATA LIST with the HDS.
7. Start the engine, and hold it between 3,500 rpm and 4,000 rpm without load (in Park or neutral) until the SOC increases to 70 %.
8. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P0A27 indicated?
YES - Go to step 9.
NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the high voltage contactor, the bypass contactor, and the MCM.

9. Turn the ignition switch OFF.
10. Turn the battery module switch OFF.
11. Remove the IPU lid.
12. Turn the ignition switch OFF, and wait at least 30 seconds.
13. Measure voltage between body ground and MCM connector terminals B12 and B13 individually.





Is there battery voltage?
YES - Go to step 26.
NO - Go to step 14.

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





Is there about 0 ohms?
YES - Replace the high voltage contactor, then go to step 16.
NO - Go to step 15.

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





Is there 38 - 42 ohms?
YES - Replace the bypass contactor, then go to step 16.
NO - Replace the MPI module, then go to step 16.

16. Turn the ignition switch OFF.
17. Reconnect all connectors.
18. Reinstall IPU lid, and turn on the battery module switch.
19. Turn the ignition switch ON (II).
20. Reset the MCM.
21. Turn the ignition switch OFF, and wait 30 seconds.
22. Turn the ignition switch ON (II).
23. Check the SOC in the DATA LIST with the HDS.
24. Start the engine, and hold it between 3,500 rpm and 4,000 rpm without load (in Park or neutral) until the SOC increases to 70 %.
25. Check for Temporary DTCs or DTCs with the HDS.
Are any Temporary DTCs or DTCs indicated?
YES - If DTC P0A27 is indicated, check for poor connections or loose terminals at the high voltage contactor, the bypass contactor, and the MCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.
NO - Troubleshooting is complete.

26. Reinstall the IPU lid, then turn the battery module switch ON.
27. Update the MCM if it does not have the latest software, or substitute a known-good MCM.
28. Turn the ignition switch OFF, and wait at least 30 seconds.
29. Check for Temporary DTCs or DTCs with the HDS.
Are any Temporary DTCs or DTCs indicated?
YES - If DTC P0A27 is indicated, check for poor connections or loose terminals at the high voltage contactor, the bypass contactor, and the MCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.
NO - If the MCM was updated, troubleshooting is complete. If the MCM was substituted, replace the original MCM.