DPFE Sensor Circuit High Input
2004-2009 Mazda Mazda3 2.0L I4
Description
The DPFE sensor circuit is reading above the maximum expected voltage. The sensor is reporting excessive EGR flow or has an electrical fault producing a high reading.
Symptoms
- Check Engine Light
- Rough idle
- Engine surge
- Poor fuel economy
- Knocking or pinging
- Failed emissions test
Common Causes
- Faulty DPFE sensor corroded internally
- DPFE sensor hoses reversed
- Clogged EGR metering orifice
- Wiring short to power
- Vacuum leak in EGR system
Diagnostic Steps
- Check DPFE sensor voltage at key-on engine-off (should be 0.45-0.55V; above 1V indicates bad sensor)
- Verify DPFE hoses are not reversed
- Inspect EGR metering orifice for blockage
- Check wiring for shorts to power
- Test sensor response to applied vacuum
Repair Notes
Replace the DPFE sensor, which is the most common cause; verify hoses are correctly connected.
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
P1401 on Other Vehicles
Common Questions
What does code P1401 mean on a 2004-2009 Mazda Mazda3?
P1401 stands for "DPFE Sensor Circuit High Input". The DPFE sensor circuit is reading above the maximum expected voltage. The sensor is reporting excessive EGR flow or has an electrical fault producing a high reading.
What are the symptoms of P1401 on a Mazda Mazda3?
Common symptoms of P1401 include: Check Engine Light, Rough idle, Engine surge, Poor fuel economy, Knocking or pinging, Failed emissions test.
What causes P1401 on a 2004-2009 Mazda Mazda3?
Common causes of P1401 include: Faulty DPFE sensor corroded internally, DPFE sensor hoses reversed, Clogged EGR metering orifice, Wiring short to power, Vacuum leak in EGR system.