P0478: Exhaust Pressure Control Valve High
MediumPowertrainExhaust System
What does P0478 mean?
P0478 is a diagnostic trouble code indicating "Exhaust Pressure Control Valve High". This code relates to your vehicle's exhaust system and should be diagnosed to determine the root cause. The severity level helps indicate how urgently this should be addressed.
Common causes
- Faulty exhaust system component
- Wiring or connector issue in the related circuit
- Failed sensor providing incorrect readings
- Software/calibration issue requiring ECU update
- Related component causing secondary fault
What should you do?
Schedule a diagnostic appointment at your earliest convenience. The vehicle is generally safe to drive short distances, but the underlying issue should be addressed to prevent it from worsening.
Get a diagnosis for YOUR car
Code P0478 can mean different things depending on your vehicle. TorqueBot gives you a diagnosis specific to your make, model, and year.