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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 (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 ETCS control relay and the ECM/PCM.

    NO  -Go to step 3.

  3. Turn the ignition switch OFF.
  4. Remove the ETCS control relay (F) from the under-hood fuse/relay box.
    Fig 1: Identifying ETCS Control Relay
    G06265820Courtesy of AMERICAN HONDA MOTOR CO., INC.
  5. Test the ETCS control relay (see 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/PCM connector A (44P).
  8. Check for continuity between ECM/PCM connector terminal A20 and body ground.
    Fig 2: Checking Continuity Between ECM/PCM Connector Terminal A20 And Body Ground
    G06265821Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

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

    NO  -Go to step 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.
    Fig 3: Measuring Voltage Between ECM/PCM Connector Terminal C1 And Body Ground
    G06265822Courtesy of AMERICAN HONDA MOTOR CO., INC.

    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 step 12.

    NO  -Go to step  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 (see ECM/PCM 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/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.

  18. Turn the ignition switch OFF.
  19. Reconnect all connectors.
  20. Update the ECM/PCM if it does not have the latest software (see UPDATING THE ECM/PCM ), or substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ).
  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/PCM. If the ECM/PCM was updated, substitute a known-good ECM/PCM (see SUBSTITUTING THE 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 (see ECM/PCM REPLACEMENT ). If any other Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.

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