Circuit Description

The camshaft position (CMP) actuator solenoid is pulse width modulated (PWM). The engine control module (ECM) controls the CMP actuator solenoid duty cycle by controlling the amount of solenoid ON time.

Ignition voltage is supplied directly to the CMP actuator solenoid. The ECM controls the solenoid by grounding the control circuit with a solid state device called a driver. The driver is equipped with a feedback circuit that is pulled-up to a voltage. The ECM can determine if the control circuit is open, shorted to ground, or shorted to a voltage by monitoring the feedback voltage. If the ECM detects the control circuit voltage is less than a predetermined value when the circuit is commanded OFF, this DTC sets.