P0A94
DTC P0A94 (48): DC-DC Converter Output Low Voltage1. Turn the ignition switch ON (II).
2. Check for Temporary DTCs or DTCs with the HDS.
Is DTC U1221 or P0562 indicated?
YES - Do the troubleshooting for DTC U1221, or DTC P0562.
NO - Go to step 3.
3. Reset the MCM.
4. Start the engine, and let it idle for 2 minutes under these conditions:
^ Headlights on high beam
^ Blower fan at maximum speed
^ Rear window defogger on
5. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P0A94 indicated?
YES - Go to step 6.
NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the DC-DC converter, +B terminal (on the underhood fuse/relay box), and the MCM.
6. Measure voltage between 12 V battery terminals + terminal and - terminal.
7. Compare the 12 V battery voltage and the MCM BACK UP VOLTAGE in the DATA LIST with the HDS.
Is there more than 2.0 V difference between 12 V battery voltage and MCM BACK UP VOLTAGE?
YES - Go to step 19.
NO - Go to step 8.
8. Turn the ignition switch OFF.
9. Check the under-hood fuse/relay box +B terminal (ORN wire) connection.
Is the connection OK?
YES - Go to step 10.
NO - Repair connection in the wire +B terminal, then go to step 13.
10. Turn the battery module switch OFF.
11. Remove the IPU lid.
12. Check the +B connector (A) on the DC-DC converter.
Is the connection OK?
YES - Replace the DC-DC converter, then go to step 13.
NO - Repair the +B connector on the DC-DC converter as necessary, then go to step 13.
13. Reconnect all connectors.
14. Reinstall the IPU lid, then turn the battery module switch ON.
15. Turn the ignition switch ON (II).
16. Reset the MCM.
17. Start the engine, and let it idle for 2 minutes under these conditions:
^ Headlights on high beam
^ Blower fan at maximum speed
^ Rear window defogger on
18. Check for Temporary DTCs or DTCs with the HDS.
Are any Temporary DTCs or DTCs indicated?
YES - If DTC P0A94 is indicated, check for poor connections or loose terminals at the DC-DC converter, under-hood fuse/relay box, 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.
19. Reinstall the IPU lid, then turn the battery module switch ON.
20. Update the MCM if it does not have the latest software, or substitute a known-good MCM.
21. Start the engine, and let it idle for 2 minutes under these conditions:
^ Headlights on high beam
^ Blower fan at maximum speed
^ Rear window defogger on
22. Check for Temporary DTCs or DTCs with the HDS.
Are any Temporary DTCs or DTCs indicated?
YES - If DTC P0A94 is indicated, check for poor connections or loose terminals at the DC-DC converter, under-hood fuse/relay box, 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.