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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), or press the engine start/stop button to select the ON mode.
  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 PCM.

    NO  -Go to step 3.

  3. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
  4. Remove the ETCS control relay (A) from the under-hood fuse/relay box.
    Fig 1: Identifying ETCS Control Relay Of Under-Hood Fuse/Relay Box
    G08072825Courtesy 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 PCM connector A (49P).
  8. Check for continuity between PCM connector terminal A29 and body ground.
    Fig 2: Checking Continuity Between PCM Connector Terminal A29 And Body Ground
    G08072826Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the PCM (A29) and the ETCS control relay, then go to step  13.

    NO  -Go to step 9.

  9. Disconnect PCM connector C (49P).
  10. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
  11. Measure the voltage between PCM connector terminal C4 and body ground.
    Fig 3: Measuring Voltage Between PCM Connector Terminal C4 And Body Ground
    G08072827Courtesy 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 ETCS control relay, then go to step 12.

    NO  -Go to step  18.

  12. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
  13. Reconnect all connectors.
  14. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
  15. Reset the PCM with the HDS.
  16. Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).
  17. Check for Pending or Confirmed DTCs with the HDS.

    Is DTC P1658 indicated? 

    YES  -Check for poor connections or loose terminals at the 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 .

  18. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
  19. Reconnect all connectors.
  20. Update the PCM if it does not have the latest software (see PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ).
  21. Check for Pending or Confirmed DTCs with the HDS.

    Is DTC P1658 indicated? 

    YES  -Check for poor connections or loose terminals at the 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 .