Circuit Description
WARNING: This page is about a different car, the 2003 Pontiac Vibe. However, it is still accessible from the selected car via links, so may be relevant.
The DTC P1656 Intake Camshaft Position (CMP) Actuator Solenoid Control Circuit diagnostic monitors the operation of CMP actuator system. CMP actuator system enables the Powertrain Control Module (PCM) to change camshaft timing when engine is running. CMP actuator solenoid valve controls oil flow that applies pressure to advance or retard the camshaft. PCM provides a Pulse Width Modulated (PWM) signal for control of CMP actuator solenoid.