CMP Actuator System Performance Diagnostic
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The engine control module (ECM) monitors the performance of the camshaft position (CMP) actuator system by monitoring the calibrated desired position, and the actual position of the camshaft, through the 4X signal of the CMP sensor. If the difference between the actual and desired position is greater than a calibrated angle, for more than a calibrated amount of time, DTC P0011 will set.
For the system descriptions covering the hydraulic/mechanical part of the CMP actuator refer to Camshaft Position Actuator and Solenoid Valve Description .