DTC Troubleshooting: P1658 (40) (R18A: M/T)

DTC Troubleshooting: P1658 (40)

DTC P1658:  Electronic Throttle Control System (ETCS) Control Relay ON Malfunction


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

1.Turn the ignition switch ON (II).

2.Do the ETCS TEST in the INSPECTION MENU with the HDS.

Is the RELAY circuit OK?


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


NO - Go to 3.


3.Turn the ignition switch OFF.

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

 

5.Test the ETCS control relay.

Is the ETCS control relay OK?


YES - Go to 6.


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


6.Jump the SCS line with the HDS.

7.Disconnect ECM/PCM connector A (44P).

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

 

Is there continuity?


YES - Repair short in the wire between the ECM/PCM (A20) and the ETCS control relay, then go to 13.


NO - Go to 9.

9.Disconnect ECM/PCM connector C (44P).

10.Turn the ignition switch ON (II).

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

 

Is there battery voltage?


YES - Repair short to power in the wire between the ECM/PCM (C1) and the ETCS control relay, then go to 12.


NO - Go to 18.

12.Turn the ignition switch OFF.

13.Reconnect all connectors.

14.Turn the ignition switch ON (II).

15.Reset the ECM/PCM with the HDS.

16.Do the ECM/PCM idle learn procedure.

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

Are any Temporary DTCs or DTCs indicated?


YES - If DTC P1658 is indicated, check for poor connections or loose terminals at the ETCS control relay and the ECM/PCM, then go to 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.


NO - Troubleshooting is complete.n


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

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

Are any Temporary DTCs or DTCs indicated?


YES - If DTC P1658 is indicated, check for poor connections or loose terminals at the ETCS control relay and the ECM/PCM, then go to 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.


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