The EGR volume control valve used a DC motor and controls the flow rate of EGR from downstream of exhaust manifold catalyst. ECM controls the DC motor to make the valve opening angle in response to driving conditions.

The EGR control valve control position sensor is built in the EGR control valve and uses a permanent magnet and a semiconductor device. This sensor measures valve shaft movements and transmits a voltage signal to ECM. Based on this signal, ECM judges the valve opening angle as of then and controls the motor to achieve opening angle appropriate to the driving conditions.