Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information

Condition




The control module checks that the camshaft is in the correct position in relation to the position of the crankshaft. If the position of the camshaft is incorrect, the control module will adjust the adaptation for the camshaft. Diagnostic trouble code (DTC) ECM-643A or ECM-644A is stored if the adaptation becomes too great.

Substitute value
None.

Possible source

Signal too high
- Poor oil quality
- Incorrectly adjusted camshafts
- The timing gear belt has jumped off the cogs
- Defective reset valve
- Mechanical fault in the variable valve timing (VVT) unit.

Signal too low
- Poor oil quality
- Incorrectly adjusted camshafts
- The timing gear belt has jumped off the cogs.

Fault symptom[s]
- Malfunction indicator lamp (MIL) lit.