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DTC P1659: ETCS Control Relay OFF 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. Clear the DTC with the HDS.
  3. Check for Pending or Confirmed DTCs with the HDS.

    Is DTC P1659 indicated? 

    YES  -Go to step 4.

    NO  -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.

  4. Turn the ignition switch to LOCK (0).
  5. Check the No. 10 DBW (ETCS) (15 A) fuse in the under-hood fuse/relay box.

    Is the fuse OK? 

    YES  -Go to step 6.

    NO  -Go to step  14.

  6. Test the ETCS control relay (built into the relay control module) (see RELAY CONTROL MODULE TEST ).

    Is the ETCS control relay OK? 

    YES  -Go to step 7.

    NO  -Replace the under-hood fuse/relay box (see DTC B1065: RELAY CONTROL MODULE LOST COMMUNICATION WITH DRIVER'S MPCS UNIT (DRLOCKSW MESSAGE) ), then go to step  22.

  7. Jump the SCS line with the HDS.
  8. Disconnect PCM connector C (49P).
  9. Disconnect under-hood fuse/relay box connector H (9P).
  10. Check for continuity between under-hood fuse/relay box connector H (9P) terminal No. 7 and PCM connector terminal C4.
    Fig 1: Checking Continuity Between Under-Hood Fuse/Relay Box Connector H (9P) Terminal No. 7 And PCM Connector Terminal C4
    G08054609Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 11.

    NO  -Repair an open in the wire between the PCM (C4) and the under-hood fuse/relay box, then go to step  22.

  11. Disconnect PCM connector A (49P).
  12. Disconnect under-hood fuse/relay box connector E (14P).
  13. Check for continuity between under-hood fuse/relay box connector E (14P) terminal No. 14 and PCM connector terminal A29.
    Fig 2: Checking Continuity Between Under-Hood Fuse/Relay Box Connector E (14P) Terminal No. 14 And PCM Connector Terminal A29
    G08054610Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step  27.

    NO  -Repair an open in the wire between the PCM (A29) and the under-hood fuse/relay box, then go to step  22.

  14. Jump the SCS line with the HDS.
  15. Disconnect PCM connector C (49P).
  16. Disconnect under-hood fuse/relay box connector H (9P).
  17. Check for continuity between PCM connector terminal C4 and body ground.
    Fig 3: Checking Continuity Between PCM Connector Terminal C4 And Body Ground
    G08054611Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the PCM (C4) and the under-hood fuse/relay box, then go to step  22.

    NO  -Go to step  18.

  18. Reconnect under-hood fuse/relay box connector H (9P), and replace the No. 10 DBW (ETCS) fuse in the under-hood fuse/relay box.
  19. Turn the ignition switch to ON (II).
  20. Measure the voltage between PCM connector terminal C4 and body ground.
    Fig 4: Measuring Voltage Between PCM Connector Terminal C4 And Body Ground
    G08054612Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step  27.

    NO  -Replace the under-hood fuse/relay box. Also replace the No. 10 DBW (ETCS) fuse in the under-hood fuse/relay box, then go to step 21.

  21. Turn the ignition switch to LOCK (0).
  22. Reconnect all connectors.
  23. Turn the ignition switch to ON (II).
  24. Reset the PCM with the HDS.
  25. Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).
  26. Check for Pending or Confirmed DTCs with the HDS.

    Is DTC P1659 indicated? 

    YES  -Check for poor connections or loose terminals at the under-hood fuse/relay box 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.

  27. Reconnect all connectors.
  28. Update the PCM if it does not have the latest software (see KNOCK SENSOR REPLACEMENT ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ).
  29. Check for Pending or Confirmed DTCs with the HDS.

    Is DTC P1659 indicated? 

    YES  -Check for poor connections or loose terminals at the under-hood fuse/relay box 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.

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