Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information

Condition




Diagnostic trouble code (DTC) ECM-644A is stored in the engine control module (ECM) if the camshaft is not in the correct position. The engine control module (ECM) registers this as a fault as soon as the engine is started.
The engine control module (ECM) registers a fault and diagnostic trouble code (DTC) ECM-644A is stored in the engine control module (ECM) if the camshaft position (CMP) sensor flanker is not correct in relation to the engine speed (RPM) sensor.
The engine control module (ECM) registers a fault and diagnostic trouble code (DTC) ECM-644A is stored in the engine control module (ECM) if the camshaft does not rotate quickly enough in response to the control signal.

Substitute value
- the variable camshaft is disabled

Possible source

Faulty position
- camshaft belt has jumped out of place on the cogs
- defective reset valve
- mechanical fault in the Variable valve timing (VVT) unit

Faulty control
- defective camshaft position (CMP) sensor

Control too slow
- low oil pressure
- poor oil quality
- defective reset valve
- mechanical fault in the Variable valve timing (VVT) unit

Fault symptom[s]
- poor performance