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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 (see GENERAL TROUBLESHOOTING INFORMATION ).
  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 under-hood fuse/relay box (ETCS control relay) and the PCM.

    NO  -Go to step 3.

  3. Turn the ignition switch to LOCK (0).
  4. Test the ETCS control relay (built into the relay control module) (see RELAY CONTROL MODULE TEST ).

    Is the ETCS control relay OK? 

    YES  -Go to step 5.

    NO  -Replace the under-hood fuse/relay box (see DTC B1065: RELAY CONTROL MODULE LOST COMMUNICATION WITH DRIVER'S MPCS UNIT (DRLOCKSW MESSAGE) ), then go to step  14.

  5. Jump the SCS line with the HDS.
  6. Disconnect PCM connector A (49P).
  7. Disconnect under-hood fuse/relay box connector E (14P).
  8. Check for continuity between PCM connector terminal A29 and body ground.
    Fig 1: Checking Continuity Between PCM Connector Terminal A29 And Body Ground
    G08054607Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the PCM (A29) and the under-hood fuse/relay box (ETCS control relay), then go to step  14.

    NO  -Go to step 9.

  9. Disconnect PCM connector C (49P).
  10. Disconnect under-hood fuse/relay box connector H (9P).
  11. Turn the ignition switch to ON (II).
  12. Measure the voltage between PCM connector terminal C4 and body ground.
    Fig 2: Measuring Voltage Between PCM Connector Terminal C4 And Body Ground
    G08054608Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Repair a short to power in the wire between the PCM (C4) and the under-hood fuse/relay box (ETCS control relay), then go to step 13.

    NO  -Go to step  19.

  13. Turn the ignition switch to LOCK (0).
  14. Reconnect all connectors.
  15. Turn the ignition switch to ON (II).
  16. Reset the PCM with the HDS.
  17. Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).
  18. Check for Pending or Confirmed DTCs with the HDS.

    Is DTC P1658 indicated? 

    YES  -Check for poor connections or loose terminals at the under-hood fuse/relay box (ETCS control relay) and the 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.

  19. Turn the ignition switch to LOCK (0).
  20. Reconnect all connectors.
  21. Update the PCM if it does not have the latest software (see KNOCK SENSOR REPLACEMENT ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ).
  22. Check for Pending or Confirmed DTCs with the HDS.

    Is DTC P1658 indicated? 

    YES  -Check for poor connections or loose terminals at the under-hood fuse/relay box (ETCS control relay) and the PCM. If the PCM was updated, substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. 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 (see PCM REPLACEMENT ). If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.

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