DTC P1404: EGR System Performance: Description

The Exhaust Gas Recirculation (EGR) valve position sensor is monitored by the Powertrain Control Module (PCM). The 5-volt reference circuit, low reference circuit, and the EGR valve position signal circuit are used by the PCM to determine the EGR valve position. When the ignition switch is turned ON, the PCM records the EGR Learned Minimum Position. The PCM compares the EGR Learned Minimum Positions parameter. If the PCM detects that the EGR valve is still open when the PCM is commanding the EGR valve closed, DTC P1404 sets.