DTC Troubleshooting

DTC Troubleshooting: P1549, P1549

DTC P1549:

Charging System High Voltage

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 a high voltage battery (24 V, etc.) is connected to the vehicle, this DTC can be stored.

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

2. Clear the DTC with the HDS.

3. Start the engine.

4. Check under these conditions:

- A/C off
- Headlights off
- Rear window defogger off

5. Hold the engine speed at 2,000 rpm (A/T in P or N, M/T in neutral) 1 minute.

6. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P1549 indicated?

YES -

Replace the alternator Removal and Replacement, then go to step 7.

NO -

Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the alternator and the under-hood fuse/relay box.

7. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

8. Reset the ECM/PCM with the HDS.

9. Do the ECM/PCM idle learn procedure ECM/PCM Idle Learn Procedure.

10. Start the engine.

11. Check under these conditions:

- A/C off
- Headlights off
- Rear window defogger off

12. Hold the engine speed at 2,000 rpm (A/T in P or N, M/T in neutral) 1 minute.

13. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P1549 indicated?

YES -

Check for poor connections or loose terminals at the alternator and the under-hood fuse/relay box, then go to step 1.

NO -

Troubleshooting is complete. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.