DTC P1404: EGR Valve Closed Pintle Position: Description
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The Powertrain Control Module (PCM) monitors the Exhaust Gas Recirculation (EGR) valve pintle position input to ensure that the valve responds properly to commands from the PCM. When the ignition switch is turned ON, the PCM learns the EGR learned minimum position. The PCM compares the EGR learned minimum position to the EGR position sensor when the EGR valve is commanded closed. If the EGR position sensor indicates that the EGR valve is still open when the PCM is commanding the EGR valve closed, this DTC will set.