P1401 Code failures by brands


Description of DTC code P1401

Diagnostic code P1401 OBD2 is a manufacturer specific code. It is also defined as "high voltage of the detected differential pressure feedback EGR sensor circuit".  This code is set when the PCM (Powertrain Control Module) finds excessively high voltage in the circuit that controls the operation of the DPFE (Differential Pressure Feedback Sensor), which is a critical part of the EGR System.

The Exhaust Gas Recirculation (EGR) System mixes a certain amount of the exhaust gas in the intake air. In this way, The EGR reduces the combustion temperatures below the point where Nitrogen Oxide (NOx) is formed. In most vehicles, the opening of the EGR valve is electronically controlled to get this result. The Ford manufacturer uses a hole in the EGR duct, which works as a pressure regulator.

When the EGR system and the different components of the system are working properly, the PCM sees the pressure difference that is proportional to the amount of gas that passes through the system hole. When there are variations in the engine speed and load, the PCM uses the signal voltage to calculate the gas recirculation strategy. So, it reduces emissions output without losing engine performance and fuel economy. In case the PCM detected a signal voltage above the right level, the error code P1401 OBDII would be set.

Symptoms of fault code P1401

  • The Check Engine lamp is on.
  • The engine does not run at idle.
  • Limited acceleration.
  • High levels of engine power loss.
  • Increased fuel consumption.
  • The vehicle does not pass the emissions tests.

Causes of OBD2 P1401

Reasons for setting the fault code P1401 OBD2:

  • The Differential Pressure Feedback Sensor may be defective. This is the most common cause.
  • The electrical circuit of the DPFE may have bad wires or connectors.
  • The EGR valve may be in bad condition.
  • Possibly a vacuum line has deficiencies.
  • Exhaust gas recirculation system lines or the exhaust may be clogged.

Possible solutions of the DTC code P1401

The steps to correct the DTC code P1401 OBDII:

  • First, it is necessary to consult the TSB (Technical Service Bulletins).
  • Check all wires, connectors, and other components of the Differential Pressure Feedback Sensor electrical circuit. If any of these devices show common damage due to burns, wear, or corrosion, make the necessary repairs.
  • Please, consult the service manual for the diagnostic steps of the Differential Pressure Feedback Sensor. If it does not pass the checks listed there, consider the sensor to be in poor condition, replace it.
  • Diagnose the Exhaust Gas Recirculation System. Check this and all its components work properly. Make the necessary corrections.

Codes related to P1401

Leave a Reply

Your email address will not be published.