DTC P1404: EGR Closed Position Performance: Description
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The Exhaust Gas Recirculation (EGR) valve position sensor is monitored by the 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 parameter to the EGR Position Sensor parameter. If the PCM detects that the EGR valve is still open when the PCM is commanding the EGR valve closed, DTC P1404 sets.