DTC P0403: EGR Solenoid Control Circuit: Description

Exhaust Gas Recirculation (EGR) valve consists of a pintle valve that moves by use of an internal solenoid and an internal position sensor (potentiometer) which is used to determine pintle valve position. EGR solenoid receives power through main relay when ignition switch is in CRANK or RUN position. ECM controls EGR solenoid by supplying a ground to EGR solenoid whenever exhaust gas needs to be recirculated into intake manifold. ECM monitors EGR solenoid control feedback and EGR sensor signal (valve position) circuits for correct voltage levels at certain times. DTC sets when ECM detects EGR solenoid control feedback voltage is between a calibrated voltage range (open circuit) when solenoid is being commanded off.