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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 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 OFF.
  4. Test the ETCS control relay in the under-hood fuse/ relay box (see POWER RELAY TEST ).

    ETCS control relay OK? 

    YES  - Go to step 5.

    NO  - Replace the relay control module (under-hood fuse/relay box) (see REMOVAL AND INSTALLATION ), then go to step  14.

  5. Jump the SCS line with the HDS.
  6. Disconnect PCM connector A (49P).
  7. Disconnect the under-hood fuse/relay box connector E (14P).
  8. Check for continuity between PCM connector terminal A29 and body ground.
    Fig 1: Identifying Continuity Between PCM Connector Terminal A29 And Body Ground
    G05485150Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair 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 the under-hood fuse/relay box connector H (9P).
  11. Turn the ignition switch ON (II).
  12. Measure voltage between PCM connector terminal C4 and body ground.
    Fig 2: Identifying Voltage Between PCM Connector Terminal C4 And Body Ground
    G05485151Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Repair 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 OFF.
  14. Reconnect all connectors.
  15. Turn the ignition switch ON (II).
  16. Reset the PCM with the HDS.
  17. Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).
  18. Check for Temporary DTCs or 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 Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.

  19. Turn the ignition switch OFF.
  20. Reconnect all connectors.
  21. Update the PCM if it does not have the latest software (see PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ).
  22. Check for Temporary DTCs or 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 Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.

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