The cam phasing system is a hydraulically actuated phase shifting mechanism. The powertrain
control module (PCM) supplies the ignition positive driver and ground circuits. A pulse width
modulated (PWM) driver controls the amount that the camshaft actuator solenoid assembly advances
or retards the exhaust camshaft. The exhaust camshaft is commanded to a maximum retard position
of 25 degrees. When the exhaust camshaft is retarded at the maximum rate, the duty cycle of the
signal is at 100 percent. The maximum advance rate has a 0 percent duty cycle. Other than when the
camshaft is at full advance, a 50 percent duty cycle is used to maintain a steady retard angle.
The driver has the ability to detect an electrical malfunction in the ignition positive or ground circuit. If
an electrical malfunction occurs, the driver signals the PCM to set this diagnostic trouble code (DTC).
A common code that can be set is p0014 or p0016 on Chevy Trailblazer, GMC Envoy, and
Cam Actuator Solenoid Description