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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 ETCS control relay and the ECM/PCM

    NO  -Go to step 3

  3. Turn the ignition switch to LOCK (0)
  4. Remove the ETCS control relay (A) from the under-hood fuse/relay box
    Fig 1: Identifying ETCS Control Relay
    G05992388Courtesy 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 (49P)
  8. Check for continuity between ECM/PCM connector terminal A21 and body ground
    Fig 2: Checking Continuity Between ECM/PCM Connector Terminal A21 And Body Ground
    G05992389Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair short in the wire between the ECM/PCM (A21) and the ETCS control relay, then go to step  13

    NO  -Go to step 9

  9. Disconnect ECM/PCM connector C (49P)
  10. Turn the ignition switch to ON (II)
  11. Measure the voltage between ECM/PCM connector terminal C1 and body ground
    Fig 3: Measuring Voltage Between ECM/PCM Connector Terminal C1 And Body Ground
    G05992390Courtesy 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 to LOCK (0)
  13. Reconnect all connectors
  14. Turn the ignition switch to 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 DTC's troubleshooting

  18. Turn the ignition switch to LOCK (0)
  19. Reconnect all connectors
  20. Update the ECM/PCM if it does not have the latest software (see ECM/PCM UPDATE ), 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 DTC's troubleshooting

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