DTC P0340: CMP Sensor 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 to 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 the CMP sensor and the PCM.
Turn the ignition switch to LOCK (0).
Disconnect the CMP sensor 3P connector.
Turn the ignition switch to ON (II).
Measure the voltage between CMP sensor 3P connector terminal No. 3 and body ground.

Fig 1: Measuring Voltage Between CMP Sensor 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 CMP sensor and PGM-FI main relay 1 (Fl MAIN), then go to step 18.
Measure the voltage between CMP sensor 3P connector terminal No. 1 and body ground.

Fig 2: Measuring Voltage Between CMP Sensor 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 the voltage between CMP sensor 3P connector terminals No. 2 and No. 3.

Fig 3: Measuring Voltage Between CMP Sensor 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 the CMP sensor and G101, then go to step 18.
Measure the voltage between PCM connector terminal B8 and body ground.

Fig 4: Measuring Voltage Between PCM Connector Terminal B8 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there about 5 V?

YES -Repair open in the wire between the PCM (B8) and the CMP sensor, then go to step 18.

NO -Go to step 12.
Turn the ignition switch to LOCK (0).
Jump the SCS line with the HDS.
Disconnect PCM connector B (24P).
Check for continuity between PCM connector terminal B8 and body ground.

Fig 5: Checking Continuity Between PCM Connector Terminal B8 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Repair short in the wire between the PCM (B8) and the CMP sensor, then go to step 18.

NO -Go to step 26.
Turn the ignition switch to LOCK (0).
Replace the CMP sensor (see CMP SENSOR REPLACEMENT ).
Reconnect all connectors.
Turn the ignition switch to ON (II).
Reset the PCM with the HDS.
Clear the CKP pattern with the HDS.
Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).
Do the CKP pattern learn procedure (see HDS CLEAR COMMAND ).
Start the engine.
Check for Temporary DTCs or DTCs with the HDS.
Is DTC P0340 indicated?

YES -Check for poor connections or loose terminals at the CMP sensor 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.
Reconnect all connectors.
Update the PCM if it does not have the latest software (see PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ).
Check for Temporary DTCs or DTCs with the HDS.
Is DTC P0340 indicated?

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