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Diagnostic Trouble Code (DTC) Information






Diagnostic trouble code (DTC) information

Condition




When the engine coolant temperature (ECT) is above 80 °C and the engine has been running for more than 2 minutes check the engine control module (ECM) camshaft adaptation ACTUAL and DESIRED values. If these values deviate too much (approximately 10 crankshaft ° for longer than 15 seconds) during " even " driving the engine control module (ECM) interprets it as a fault and diagnostic trouble code (DTC) ECM-640A is stored.

Substitute value
- none

Possible source

Incorrect signal
- camshaft belt has jumped out of place on the cogs
- low oil pressure / bad oil quality
- defective reset valve
- mechanical fault in the Variable valve timing (VVT) unit

Fault symptom[s]
- uneven idle
- increased emissions