DPFE Sensor Circuit Low Input
2014-2018 Mazda Mazda3 2.5L I4
Description
The Differential Pressure Feedback EGR sensor circuit is reading below the minimum expected voltage. The DPFE sensor measures exhaust gas flow through the EGR valve by detecting a pressure differential.
Symptoms
- Check Engine Light
- Rough idle
- Stalling
- Poor fuel economy
- Failed emissions test
Common Causes
- Faulty DPFE sensor (most common)
- Clogged DPFE sensor hoses
- Wiring short to ground
- Corroded DPFE sensor from moisture
- EGR passage blockage
Diagnostic Steps
- Check DPFE sensor voltage at key-on engine-off (should be 0.45-0.55V)
- Inspect DPFE sensor hoses for cracks or blockage
- Test DPFE sensor wiring for shorts
- Check for carbon buildup in EGR passages
- Replace DPFE sensor and retest
Repair Notes
Replace the DPFE sensor, which commonly fails from moisture corrosion; inspect and clean EGR passages.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0011Intake Camshaft Position Timing Over-Advanced Bank 1
- P0012Intake Camshaft Position Timing Over-Retarded Bank 1
- P0013Exhaust Camshaft Position Actuator Circuit/Open Bank 1
- P0014Exhaust Camshaft Position Timing Over-Advanced Bank 1
- P0015Exhaust Camshaft Position Timing Over-Retarded Bank 1
P1400 on Other Vehicles
Common Questions
What does code P1400 mean on a 2014-2018 Mazda Mazda3?
P1400 stands for "DPFE Sensor Circuit Low Input". The Differential Pressure Feedback EGR sensor circuit is reading below the minimum expected voltage. The DPFE sensor measures exhaust gas flow through the EGR valve by detecting a pressure differential.
What are the symptoms of P1400 on a Mazda Mazda3?
Common symptoms of P1400 include: Check Engine Light, Rough idle, Stalling, Poor fuel economy, Failed emissions test.
What causes P1400 on a 2014-2018 Mazda Mazda3?
Common causes of P1400 include: Faulty DPFE sensor (most common), Clogged DPFE sensor hoses, Wiring short to ground, Corroded DPFE sensor from moisture, EGR passage blockage.