EGR Control Module: Description and Operation

The EGR controller sends electrical signals to the vacuum switching valve after it receives information on coolant temperature, engine speed and injection pump control lever opening angle from the thermo switch, engine speed sensor and control lever position sensor respectively. The speed sensor is an electromagnetic pickup that transforms the movement of gear teeth in the injection pump into an electrical signal. The control lever position sensor is a potentiometer that varies resistance values according to changes in control lever position.