What does it mean?
P1403 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: DPFE Sensor Circuit High Input .
Symptoms
- MIL on, frequently shortly after EGR related service work
- Rough idle and a stumble just off idle
- Hesitation and mild surging while cruising
- Stalling on deceleration in some cases
- Higher fuel consumption and an emissions test failure
Likely causes
- DPFE hoses swapped after service, inverting the pressure signal
- Signal circuit shorted to the reference voltage or to battery positive
- Open sensor ground pushing the output high
- Blocked, collapsed or soot filled hose
- Failed DPFE sensor with the output stuck high
- Restricted EGR tube or metering orifice giving an abnormal pressure difference
- Corroded connector or a spread terminal
How to fix it
- Check the hose routing first: the upstream and downstream connections must go to the correct sensor ports
- Read the DPFE voltage with the key on and the engine off and compare with the specified rest value
- Inspect the hoses for soot blockage, cracking and heat hardening, and replace hardened rubber with the correct heat resistant type
- Check the sensor ground continuity and test the signal wire for a short to voltage
- Clean the EGR tube and metering orifice if they are restricted
- Replace the sensor when hoses and wiring check good but the value stays high
- Verify EGR flow and DPFE response in live data during a road test