DTC Troubleshooting

DTC Troubleshooting: P1658

DTC P1658: ETCS Control Relay ON 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. Do the ETCS TEST in the INSPECTION MENU with the HDS.

Is the RELAY circuit OK?
YES - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the ETCS control relay and the ECM.

NO - Go to step 3.


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

4. Remove the ETCS control relay (F) from the under-hood fuse/relay box.






5. Test the ETCS control relay. Power Relay Test

Is the ETCS control relay OK?
YES - Go to step 6.

NO - Replace the ETCS control relay, then go to step 13.


6. Jump the SCS line with the HDS.

7. Disconnect ECM connector A (44P).

8. Check for continuity between ECM connector terminal A20 and body ground.

Is there continuity?
YES - Repair short in the wire between the ECM (A20) and the ETCS control relay, then go to step 13.

NO - Go to step 9.






9. Disconnect ECM connector C (44P).

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

11. Measure the voltage between ECM connector terminal C1 and body ground.

Is there battery voltage?
YES - Repair short to power in the wire between the ECM (C1) and the ETCS control relay, then go to step 12.

NO - Go to step 18.






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

13. Reconnect all connectors.

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

15. Reset the ECM with the HDS.

16. Do the ECM idle learn procedure. ECM Idle Learn Procedure

17. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P1658 indicated?
YES - Check for poor connections or loose terminals at the ETCS control relay and the ECM, then go to step 1.

NO - Troubleshooting is complete. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.


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

19. Reconnect all connectors.

20. Update the ECM if it does not have the latest software, ECM Update or substitute a known-good ECM. Initial Inspection and Diagnostic Overview

21. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P1658 indicated?
YES - Check for poor connections or loose terminals at the ETCS control relay and the ECM. If the ECM was updated, substitute a known-good ECM, Initial Inspection and Diagnostic Overview then recheck. If the ECM was substituted, go to step 1.

NO - If the ECM was updated, troubleshooting is complete. If the ECM was substituted, replace the original ECM. Service and Repair If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.