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DTC P0340: CMP Sensor A No Signal

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 ON (II).
  2. Clear the DTC with the HDS.
  3. Start the engine.
  4. Check for Temporary DTCs or DTCs with the HDS.

    Is DTC P0340 indicated? 

    YES  -Go to step 5.

    NO  -Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at CMP sensor A and the ECM/PCM.

  5. Turn the ignition switch OFF.
  6. Disconnect CMP sensor A 3P connector.
  7. Turn the ignition switch ON (II).
  8. Measure voltage between CMP sensor A 3P connector terminal No. 3 and body ground.
    Fig 1: Measuring Voltage Between CMP Sensor A 3P Connector Terminal 3 And Body Ground
    G06264654Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 9.

    NO  -Repair open in the wire between CMP sensor A and the No. 3 ALTERNATOR (10 A) fuse then go to step  18.

  9. Measure voltage between CMP sensor A 3P connector terminal No. 1 and body ground.
    Fig 2: Measuring Voltage Between CMP Sensor A 3P Connector Terminal 1 And Body Ground
    G06264655Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    YES  -Go to step 10.

    NO  -Go to step  11.

  10. Measure voltage between CMP sensor A 3P connector terminals No. 2 and No. 3.
    Fig 3: Measuring Voltage Between CMP Sensor A 3P Connector Terminals 2 And 3
    G06264656Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step  16.

    NO  -Repair open in the wire between CMP sensor A and G101; A/T model (see ENGINE WIRE HARNESS (A/T) ), M/T model (see ENGINE WIRE HARNESS (M/T) ), then go to step  18.

  11. Turn the ignition switch OFF.
  12. Jump the SCS line with the HDS.
  13. Disconnect ECM/PCM connector C (44P).
  14. Check for continuity between ECM/PCM connector terminal C41 and body ground.
    Fig 4: Checking Continuity Between ECM/PCM Connector Terminal C41 And Body Ground
    G06264657Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair short in the wire between the ECM/ PCM (C41) and CMP sensor A, then go to step  18.

    NO  -Go to step 15.

  15. Check for continuity between CMP sensor A 3P connector terminal No. 1 and ECM/PCM connector terminal C41.
    Fig 5: Checking Continuity Between CMP Sensor A 3P Connector Terminal 1 And ECM/PCM Connector Terminal C41
    G06264658Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step  23.

    NO  -Repair open in the wire between the ECM/ PCM (C41) and CMP sensor A, then go to step  18.

  16. Turn the ignition switch OFF.
  17. Replace CMP sensor A (see CMP SENSOR A REPLACEMENT  ).
  18. Reconnect all connectors.
  19. Turn the ignition switch ON (II).
  20. Reset the ECM/PCM with the HDS.
  21. Do the ECM/PCM idle learn procedure (see ECM/PCM IDLE LEARN PROCEDURE ).
  22. Check for Temporary DTCs or DTCs with the HDS.

    Is DTC P0340 indicated? 

    YES  -Check for poor connections or loose terminals at CMP sensor A 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 .

  23. Reconnect all connectors.
  24. Update the ECM/PCM if it does not have the latest software (see UPDATING THE ECM/PCM ), or substitute a known- good ECM/PCM (see SUBSTITUTING THE ECM/PCM ).
  25. Check for Temporary DTCs or DTCs with the HDS.

    Is DTC P0340 indicated? 

    YES  -Check for poor connections or loose terminals at CMP sensor A 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 .