Circuit Description

The coil of the exhaust gas recirculation (EGR) valve has 12 volts supplied to it by an ignition voltage circuit. The control circuit of the EGR valve is a pulse width modulated (PWM) ground produced by an internal low side driver of the engine control module (ECM). The ECM monitors the position of the EGR pintle through the EGR position sensor. The EGR position sensor sends a feedback voltage on the signal circuit to the ECM. This voltage varies depending on the position of the EGR valve pintle. The ECM interprets this voltage as the position of the EGR valve pintle. If the ECM determines that EGR valve pintle is open during crank, DTC P0402 sets.