DTC P0403: Exhaust Gas Recirculation (EGR) Control Circuit Malfunction: General Description

The exhaust gas recirculation (EGR) system re-burns the exhaust gas by recirculating a some of it into the induction system in order to reduce oxides of nitrogen (NOx).

The powertrain control module (PCM) controls the recirculation of the exhaust gas by controlling the opening and closing of the EGR valve.

The PCM reads the return signal of the EGR valve control signal output, and when the return signal against the EGR valve control signal does not change and this condition continues for a certain time, a malfunction is detected and a DTC is stored.