EGR Valve: Description and Operation

EGR VALVE CIRCUITS

Linear EGR Valve:

The exhaust gas recirculation (EGR) valve consists of the following circuits:
- An ignition 1 voltage circuit which supplies 12 volts to the coil of the EGR valve
- Two control circuits which grounds the coil of the EGR valve-The control circuit is a pulse width modulated (PWM) ground produced by an internal low side driver of the engine control module (ECM).
- A 5-volt reference circuit supplied from the ECM to the internal position sensor of the EGR valve
- A signal circuit which sends a feedback voltage from the internal position sensor of the EGR valve 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.
- A low reference circuit supplied from the ECM to the internal position sensor of the EGR valve