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Home >> Acura >> 2009 >> RDX >> Repair and Diagnosis >> Engine Performance >> System >> Variable Valve Timing And Lift Electronic Control (VTEC) >> DTC Troubleshooting >> DTC P0340: CMP Sensor A No Signal
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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 PCM.

  5. Turn the ignition switch OFF.
  6. Disconnect the 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 No. 3 And Body Ground
    G05447029Courtesy 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 IG1 ACG (15 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 No. 1 And Body Ground
    G05447030Courtesy 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 No. 2 And No. 3
    G05447031Courtesy 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 (see ENGINE WIRE HARNESS ), then go to step  18.

  11. Turn the ignition switch OFF.
  12. Jump the SCS line with the HDS.
  13. Disconnect PCM connector C (44P).
  14. Check for continuity between PCM connector terminal C41 and body ground.
    Fig 4: Checking Continuity Between PCM Connector Terminal C41 And Body Ground
    G05447032Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair short in the wire between the 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 PCM connector terminal C41.
    Fig 5: Checking Continuity Between CMP Sensor A 3P Connector Terminal No. 1 And PCM Connector Terminal C41
    G05447033Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step  23.

    NO  - Repair open in the wire between the 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 PCM with the HDS.
  21. Do the PCM idle learn procedure (see 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 PCM, then go to step  1.

    NO  - Troubleshooting is complete. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.

  23. Reconnect all connectors.
  24. Update the PCM if it does not have the latest software (see PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE 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 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 DTCs troubleshooting.