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 ).

Turn the ignition switch ON (II).
Clear the DTC with the HDS.
Start the engine.
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.
Turn the ignition switch OFF.
Disconnect the CMP sensor A 3P connector.
Turn the ignition switch ON (II).
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
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES -Go to step 9.

NO -Repair open in the wire between the No. 18 ACC (15 A) fuse in the under-dash fuse/relay box and CMP sensor A, then go to step 18.
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
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there about 5 V?

YES -Go to step 10.

NO -Go to step 11.
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
Courtesy 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, then go to step 18.
Measure voltage between ECM/PCM connector terminal A19 and body ground.

Fig 4: Measuring Voltage Between ECM/PCM Connector Terminal A19 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there about 5 V?

YES -Repair open in the wire between the ECM/PCM (A19) and CMP sensor A, then go to step 18.

NO -Go to step 12.
Turn the ignition switch OFF.
Jump the SCS line with the HDS.
Disconnect ECM/PCM connector A (31P).
Check for continuity between ECM/PCM connector terminal A19 and body ground.

Fig 5: Checking Continuity Between ECM/PCM Connector Terminal A19 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Repair short in the wire between the ECM/PCM (A19) and CMP sensor A, then go to step 18.

NO -Go to step 23.
Turn the ignition switch OFF.
Replace CMP sensor A (see CMP SENSOR A REPLACEMENT ).
Reconnect all connectors.
Turn the ignition switch ON (II).
Reset the ECM/PCM with the HDS.
Do the ECM/PCM idle learn procedure (see ECM/PCM IDLE LEARN PROCEDURE ).
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.
Reconnect all connectors.
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 ).
Start the engine, and let it idle.
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 go to step 25. 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; '04-05 models (see '04-05 MODELS ), '06-08 models (see '06-08 MODELS ). If any other Temporary DTCs or DTC's are indicated, go to the indicated DTC's troubleshooting.