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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

    3. 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 From Under-Hood Fuse/Relay Box
    G05987475Courtesy of AMERICAN HONDA MOTOR CO., INC.
  5. Test the ETCS control relay (see POWER RELAY TEST )

    6. 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
    G05987476Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair 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
    G05987477Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Repair 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

    18. 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 ECM/PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE ECM/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 ECM/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 ECM/PCM REPLACEMENT ) If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting

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