EGR Valve: Description and Operation

Exhaust Gas Recirculation (EGR) Valve and Position Sensor







The control current from the engine control module (ECM) operates the DC motor to control the lift amount of the EGR valve. Also, a valve position sensor is provided at the rear of the motor to feed actual valve lift amount back to the ECM for more precise control of the EGR amount. The EGR valve position sensor is applied with reference voltage (5 volts) at all times from the ECM to detect the EGR valve lift amount in the form of voltage change and sends its signal to the ECM.