DTC Troubleshooting

DTC Troubleshooting: P0685

DTC P0685:

PCM Power Control Circuit/Internal Circuit Malfunction

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 problem doesn't return after you clear the DTC, or if this DTC is stored intermittently, check for loose terminals at the IGP line connectors before replacing the PCM.

1. Turn the ignition switch to ON (II).

2. Clear the DTC with the HDS.

3. Start the engine, and let it idle for 30 seconds.

4. Turn the ignition switch to LOCK (0).

5. Start the engine, and let it idle for 30 seconds.

6. Turn the ignition switch to LOCK (0).

7. Turn the ignition switch to ON (II).

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

Is DTC P0685 indicated?

YES -

Go to step 9.

NO -

Intermittent failure, the system is OK at this time.�

9. Update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM.

10. Start the engine, and let it idle for 30 seconds.

11. Turn the ignition switch to LOCK (0).

12. Start the engine, and let it idle for 30 seconds.

13. Turn the ignition switch to LOCK (0).

14. Turn the ignition switch to ON (II).

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

Is DTC P0685 indicated?

YES -

If the PCM was updated, substitute a known-good PCM, then go to step 10. If the PCM was substituted, go to step 1.

NO -

If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM Service and Repair. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.�