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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 ).
  • Information marked with an asterisk (*1) applies to '09-11 models.
  • Information marked with an asterisk (*2) applies to '12 model.
  1. Turn the ignition switch to ON (II).
  2. Clear the DTC with the HDS.
  3. Check for Temporary DTCs or 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 ETCS control relay and the PCM. ■

  4. Turn the ignition switch to LOCK (0).
  5. Check the No. 9 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  17.

  6. 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
    G05964568Courtesy of AMERICAN HONDA MOTOR CO., INC.
  7. Do the ETCS control relay test (see POWER RELAY TEST ).

    Is the ETCS control relay OK? 

    YES  -Go to step 8.

    NO  -Replace the ETCS control relay, then Go to step  23.

  8. Turn the ignition switch to ON (II).
  9. Measure the voltage between ETCS control relay 4P connector terminal No. 3 and body ground.
    Fig 2: Measuring Voltage Between ETCS Control Relay 4P Connector Terminal No. 3 And Body Ground
    G05964569Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 10.

    NO  -Replace the under-hood fuse/relay box (see REMOVAL AND INSTALLATION ), then Go to step  22.

  10. Measure the voltage between ETCS control relay 4P connector terminal No. 1 and body ground.
    Fig 3: Measuring Voltage Between ETCS Control Relay 4P Connector Terminal No. 1 And Body Ground
    G05964570Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 11.

    NO  -Replace the under-hood fuse/relay box (see REMOVAL AND INSTALLATION ), then Go to step  22.

  11. Turn the ignition switch to LOCK (0).
  12. Jump the SCS line with the HDS.
  13. Disconnect PCM connector C (49P).
  14. Check for continuity between ETCS control relay 4P connector terminal No. 2 and PCM connector terminal C4.
    Fig 4: Checking Continuity Between ETCS Control Relay 4P Connector Terminal No. 2 And PCM Connector Terminal C4
    G00511703Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 15.

    NO  -Repair open in the wire between the PCM (C4) and the ETCS control relay, then Go to step  23.

  15. Disconnect PCM connector A (49P).
  16. Check for continuity between PCM connector terminal A29 and ETCS control relay 4P connector terminal No. 4.
    Fig 5: Checking Continuity Between ETCS Control Relay 4P Connector Terminal No. 4 And PCM Connector Terminal A29
    G05964572Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step  28.

    NO  -Repair open in the wire between the PCM (A29) and the ETCS control relay, then Go to step  23.

  17. Remove the ETCS control relay (A) from the under-hood fuse/relay box.
    Fig 6: Identifying ETCS Control Relay From Under-Hood Fuse/Relay Box
    G05964573Courtesy of AMERICAN HONDA MOTOR CO., INC.
  18. Jump the SCS line with the HDS.
  19. Disconnect PCM connector C (49P).
  20. Check for continuity between PCM connector terminal C4 and body ground.
    Fig 7: Checking Continuity Between PCM Connector Terminal C4 And Body Ground
    G00511704Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair short in the wire between the PCM (C4) and the ETCS control relay, then Go to step  23.

    NO  -Go to step 21.

  21. Check for continuity between ETCS control relay 4P connector terminal No. 1 and body ground.
    Fig 8: Checking Continuity Between ETCS Control Relay 4P Connector Terminal No. 1 And Body Ground
    G05964575Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Replace the under-hood fuse/relay box (see REMOVAL AND INSTALLATION ), then Go to step  23.

    NO  -Go to step  28.

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

    Is DTC P1659 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 Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting. ■

  28. Reconnect all connectors.
  29. Update the PCM if it does not have the latest software (see PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ).
  30. Check for Temporary DTCs or DTCs with the HDS.

    Is DTC P1659 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 Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting. ■

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