P1405 - FAULT CODE - OBD2

P1405 FORD, LINCOLN, MERCURY: DPF EGR SENSOR CIRCUIT HIGH VOLTAGE DETECTED

P1405 BMW: HEATED CATALYST POWER SWITCH OVERTEMPERATURE CONDITION BANK 2

P1405 BUICK, CADILLAC, CHEVROLET, GMC: EXHAUST GAS RECIRCULATION SYSTEM VALVE 3.

P1405 HYUNDAI: EGR INCORRECT TEMPERATURE.

P1405 MAZDA: DPFE UPSTREAM HOSE OFF OR PLUGGED.

P1405 TOYOTA: TURBO PRESSURE SENSOR CIRCUIT.

The EGR system aims to limit the production of nitrogen oxide emissions by redirecting them to the upper engine inlet. In this way, they are mixed with the air-fuel charge. As a result, the fuel mixture is burned at low temperatures, and consequently, fuel chamber temperatures are reduced, achieving a reduction in NOx emissions.

The Ford manufacturer controls the EGR/DPFE system directly from the PCM. These use the EGR valve, an electronic vacuum regulator that is known as EVR, and an electronic Differential Pressure Feedback EGR Sensor (DPFE). This measures the EGR flow, and it is located inside a tube in the system. When the valve is open, a pressure differential is created across the orifice.

The P1405 OBD2 diagnostic code is a manufacturer-specific code. Its setting occurs when the Powertrain Control Module finds a negative exhaust flow during engine operation with the EGR (Exhaust Gas Recirculation) valve in the closed position. Although this code does not directly refer to an EGR valve problem, the PCM uses certain valve needle position data as a setting parameter for this code.

• Check Engine light is on.
• Multiple error codes are
• Lower fuel efficiency.
• Irregularities during idling.
• Loss of engine power.
• A strong smell of fuel.
• When performing emissions tests, the vehicle does not pass these tests.

The reasons for the P1405 OBDII DTC P1405 being stored are:

• Exhaust gas feed lines may be clogged or leaking.
• The electronic differential pressure feedback circuit harness may have burned or wear damage.
• The DPFE sensor may be defective.

The steps to troubleshoot the P1405 OBD2 fault code are as follows:

• To begin the diagnosis, consult the TSBs (Technical Service Bulletins). These have useful information.
• Inspect that the exhaust gas lines are in good condition. If you detect any leaks, you should make the necessary repairs or changes.
• Check the wiring that is related to the DPFE sensor If you discover burnt wires, or corroded connectors, repair or replace them as required.
• Consult the vehicle's reliable source of information for DPFE Sensor diagnostic steps. If you determine that the DPFE Sensor is defective, you must replace it.