DTC Troubleshooting

DTC Troubleshooting: P1659, P1659

DTC P1659:

ETCS Control Relay OFF 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.

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

2. Clear the DTC with the HDS.

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

Is DTC P1659 indicated?

YES -

Go to step 4.

NO -

Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the ETCS control relay and the ECM/PCM.�

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

5. Check the No. 18 DBW (ETCS) (15 A) fuse in the under-hood fuse/relay box.

Is the fuse OK?

YES -

Go to step 6.

NO -

Go to step 17.

6. Remove the ETCS control relay (A) from the under-hood fuse/relay box.





7. Test the ETCS control relay Testing and Inspection.

Is the ETCS control relay OK?

YES -

Go to step 8.

NO -

Replace the ETCS control relay, then go to step 23.

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

9. Measure the voltage between ETCS control relay 4P connector terminal No. 4 and body ground.





Is there battery voltage?

YES -

Go to step 10.

NO -

Check the under-hood fuse/relay box, and replace it if needed Under-Hood Fuse/Relay Box Removal and Installation, then go to step 22.

10. Measure the voltage between ETCS control relay 4P connector terminal No. 1 and body ground.





Is there battery voltage?

YES -

Go to step 11.

NO -

Check the under-hood fuse/relay box, and replace it if needed Under-Hood Fuse/Relay Box Removal and Installation, then go to step 22.

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

12. Jump the SCS line with the HDS.

13. Disconnect ECM/PCM connector C (49P).

14. Check for continuity between ETCS control relay 4P connector terminal No. 2 and ECM/PCM connector terminal C1.





Is there continuity?

YES -

Go to step 15.

NO -

Repair open in the wire between the ECM/PCM(C1) and the ETCS control relay, then go to step 23.

15. Disconnect ECM/PCM connector A (49P).

16. Check for continuity between ETCS control relay 4P connector terminal No. 3 and ECM/PCM connector terminal A21.





Is there continuity?

YES -

Go to step 28.

NO -

Repair open in the wire between the ECM/PCM(A21) and the ETCS control relay, then go to step 23.

17. Remove the ETCS control relay (A) from the under-hood fuse/relay box.





18. Jump the SCS line with the HDS.

19. Disconnect ECM/PCM connector C (49P).

20. Check for continuity between ECM/PCM connector terminal C1 and body ground.





Is there continuity?

YES -

Repair short in the wire between the ECM/PCM(C1) and the ETCS control relay, then go to step 23.

NO -

Go to step 21.

21. Check for continuity between ETCS control relay 4P connector terminal No. 1 and body ground.





Is there continuity?

YES -

Check the under-hood fuse/relay box, and replace it if needed Under-Hood Fuse/Relay Box Removal and Installation, then go to step 23.

NO -

Go to step 28.

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

23. Reconnect all connectors.

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

25. Reset the ECM/PCM with the HDS.

26. Do the ECM/PCM idle learn procedure ECM/PCM Idle Learn Procedure (M/T).

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

Is DTC P1659 indicated?

YES -

Check for poor connections or loose terminals at the ETCS control relay and the ECM/PCM, 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.�

28. Reconnect all connectors.

29. Update the ECM/PCM if it does not have the latest software ECM/PCM Update (M/T), or substitute a known-good ECM/PCM.

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

Is DTC P1659 indicated?

YES -

Check for poor connections or loose terminals at the ETCS control relay and the ECM/PCM. If the ECM/PCM was updated, substitute a known-good ECM/PCM, then recheck. If the ECM/PCM was substituted, go to step 1.

NO -

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