P16BC

DTC P16BC: Alternator FR Terminal Circuit/IGP Circuit Low Voltage

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information.

1. Check for poor connections at the alternator 4P connector.

Are the connections OK?

YES - Go to step 2.

NO - Reconnect or repair the connector, then go to step 19.

2. Turn the ignition switch ON (II).
3. Clear the DTC with the HDS.
4. Start the engine.
5. Check under these conditions:
- A/C on
- Temperature control on maximum cool
- Blower fan at maximum speed
- Rear window defogger on
- Headlights on high beam

6. Hold the engine speed at 2,000 rpm (in Park or neutral) for 1 minute.
7. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P16BC indicated?

YES - Go to step 8.

NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the alternator.

8. Turn the ignition switch OFF.
9. Disconnect the alternator 4P connector.
10. Turn the ignition switch ON (II).




11. Measure voltage between alternator 4P connector terminal No. 1 and body ground.

Is there battery voltage?

YES - Go to step 12.

NO - Repair open in the wire between the alternator (IG1 line) and the No. 18 ACG (15 A) fuse in under-dash fuse/relay box, then go to step 18.




12. Measure voltage between alternator 4P connector terminal No. 4 and body ground.

Is there about 5 V?

YES - Replace the alternator, then go to step 18.

NO - Go to step 13.

13. Turn the ignition switch OFF.
14. Jump the SCS line with the HDS.
15. Disconnect PCM connector A (31P).




16. Connect alternator 4P connector terminal No. 4 to body ground with a jumper wire.




17. Check for continuity between PCM connector terminal A12 and body ground.

Is there continuity?

YES - Go to step 26.

NO - Repair open in the wire between the PCM (A12) and the alternator, then go to step 18.

18. Reconnect all connectors.
19. Turn the ignition switch ON (II).
20. Reset the PCM with the HDS.
21. Do the PCM idle learn procedure.
22. Start the engine.
23. Check under these conditions:
- A/C on
- Temperature control on maximum cool
- Blower fan at maximum speed
- Rear window defogger on
- Headlights on high beam

24. Hold the engine speed at 2,000 rpm (in Park or neutral) for 1 minute.
25. Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?

YES - If DTC P16BC is indicated, check for poor connections or loose terminals at the alternator and the PCM, 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. Update the PCM if it does not have the latest software, or substitute a known-good PCM.
27. Start the engine.
28. Check under these conditions:
- A/C on
- Temperature control on maximum cool
- Blower fan at maximum speed
- Rear window defogger on
- Headlights on high beam

29. Hold the engine speed at 2,000 rpm (in Park or neutral) for 1 minute.
30. Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?

YES - If DTC P16BC is indicated, check for poor connections or loose terminals at the alternator and the PCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.

NO - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM.