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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 ETCS control relay and the PCM.

  4. Turn the ignition switch to LOCK (0).
  5. Check the No. 52 ETCS (15 A) fuse in the under-dash fuse/relay box.

    Is the fuse OK? 

    YES  -Go to step 6.

    NO  -Go to step  19.

  6. Open the fuse access panel (A), then remove the ETCS control relay (B) from the under-dash fuse/relay box.
    Fig 1: Identifying Fuse Access Panel And ETCS Control Relay
    G08092413Courtesy of AMERICAN HONDA MOTOR CO., INC.
  7. Test the ETCS control relay (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  25.

  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
    G08092414Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 10.

    NO  -Replace the under-dash fuse/relay box (USA model) (see REMOVAL AND INSTALLATION ), (Canada model) (see CANADA MODEL ), then go to step  24.

  10. Measure the voltage between ETCS control relay 4P connector terminal No. 2 and body ground.
    Fig 3: Measuring Voltage Between ETCS Control Relay 4P Connector Terminal No. 2 And Body Ground
    G08092415Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 11.

    NO  -Replace the under-dash fuse/relay box (USA model) (see REMOVAL AND INSTALLATION ), (Canada model) (see CANADA MODEL ), then go to step  24.

  11. Turn the ignition switch to LOCK (0).
  12. Jump the SCS line with the HDS.
  13. Disconnect PCM connector C (49P).
  14. Connect ETCS control relay 4P connector terminal No. 1 to body ground with a jumper wire.
    Fig 4: Connecting ETCS Control Relay 4P Connector Terminal No. 1 To Body Ground Using Jumper Wire
    G08092416Courtesy of AMERICAN HONDA MOTOR CO., INC.
  15. Check for continuity between PCM connector terminal C1 and body ground.
    Fig 5: Checking Continuity Between PCM Connector Terminal C1 And Body Ground
    G08092417Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 16.

    NO  -Repair an open in the wire between the PCM (C1) and the ETCS control relay, then go to step  25.

  16. Disconnect PCM connector A (49P).
  17. Connect ETCS control relay 4P connector terminal No. 4 to body ground with the jumper wire.
    Fig 6: Connecting ETCS Control Relay 4P Connector Terminal No. 4 To Body Ground Using Jumper Wire
    G08092418Courtesy of AMERICAN HONDA MOTOR CO., INC.
  18. Check for continuity between PCM connector terminal A38 and body ground.
    Fig 7: Checking Continuity Between PCM Connector Terminal A38 And Body Ground
    G08092419Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step  30.

    NO  -Repair an open in the wire between the PCM (A38) and the ETCS control relay, then go to step  25.

  19. Open the fuse access panel (A), then remove the ETCS control relay (B) from the under-dash fuse/relay box.
    Fig 8: Identifying Fuse Access Panel And ETCS Control Relay
    G08092420Courtesy of AMERICAN HONDA MOTOR CO., INC.
  20. Jump the SCS line with the HDS.
  21. Disconnect PCM connector C (49P).
  22. Check for continuity between PCM connector terminal C1 and body ground.
    Fig 9: Checking Continuity Between PCM Connector Terminal C1 And Body Ground
    G08092421Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the PCM (C1) and the ETCS control relay, then go to step  25.

    NO  -Go to step 23.

  23. Check for continuity between ETCS control relay 4P connector terminal No. 2 and body ground.
    Fig 10: Checking Continuity Between ETCS Control Relay 4P Connector Terminal No. 2 And Body Ground
    G08092422Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Replace the under-dash fuse/relay box (USA model) (see REMOVAL AND INSTALLATION ), (Canada model) (see CANADA MODEL ), then go to step  25.

    NO  -Go to step  30.

  24. Turn the ignition switch to LOCK (0).
  25. Reconnect all connectors.
  26. Turn the ignition switch to ON (II).
  27. Reset the PCM with the HDS.
  28. Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).
  29. 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 Pending or Confirmed DTCs are indicated, go to the indicated DTC'S TROUBLESHOOTING .

  30. Reconnect all connectors.
  31. Update the PCM if it does not have the latest software (see PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ).
  32. 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. 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 .