Technical Definition:
Exhaust Pressure Control Valve High
Trouble Code: P0478
Address: 0x0478
System: Powertrain
Subsystem: Auxiliary Emission Controls
Address: 0x0478
System: Powertrain
Subsystem: Auxiliary Emission Controls
Technical Description:
Possible Causes:
Possible Symptoms:
Exhaust Pressure Control Valve High
Possible Solutions:
OBD-II Trouble Code Type:
Diagnostic Step:
Tech Notes:
– Faulty Exhaust Back Pressure Valve
– Exhaust Back Pressure Valve harness is open or shorted
– Exhaust Back Pressure Valve circuit poor electrical connection