DTC Troubleshooting: P0340 (57-1), P0344 (57-2)

DTC P0340 (57-1):  CMP Sensor No Signal
  
  

1.Reset the ECM/PCM.

2.Start the engine.

Is DTC P0340 and/or P0344 indicated?


YES - Go to 3.


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


3.Turn the ignition switch OFF.

4.Disconnect the CMP sensor 3P connector.

5.Turn the ignition switch ON (II).

6.Measure voltage between CMP sensor 3P connector terminal No. 3 and body ground.

 

Is there battery voltage?


YES - Go to 7.


NO - Check the No. 4 ACG (10A) fuse in the under-dash fuse/relay box. If the fuse is OK, repair open in the wire between the CMP sensor and No. 4 ACG (10A) fuse.

7.Measure voltage between CMP sensor 3P connector terminal No. 1 and body ground.

 

Is there about 5 V?


YES - Go to 8.


NO - Go to 10.


8.Measure voltage between CMP sensor 3P connector terminals No. 2 and No. 3.

 

Is there battery voltage?


YES - Go to 9.


NO - Repair open in the wire between the CMP sensor and G101.n


9.Substitute a known-good CMP sensor and recheck.

Is DTC P0340 and/or P0344 indicated?


YES - Substitute a known-good ECM/PCM and recheck. If symptom/indication goes away, replace the original  ECM/ PCM.n


NO - Replace the original  CMP sensor.n

10.Measure voltage between ECM/PCM connector terminal A25 and body ground.

 

Is there about 5 V?


YES - Repair open in the wire between the ECM/ PCM (A25) and CMP sensor.n


NO - Go to 11.


11.Turn the ignition switch OFF.

12.Disconnect the negative cable from the battery.

13.Disconnect ECM/PCM connector A (31P).

14.Check for continuity between ECM/ PCM connector terminal A25 and body ground.

 

Is there continuity?


YES - Repair short in the wire between the ECM/ PCM (A25) and the CMP sensor.n


NO - Substitute a known-good ECM/PCM and recheck. If symptom/indication goes away, replace the original  ECM/ PCM.n