U0055 Diagnostic Trouble Code

U0055 is a kind of OBD-II Diagnostic U-Network Diagnostic Trouble Code.

It is considered generic because it applies to all makes and models of vehicles, although specific repair steps may be different depending on your car model.

Symptoms

Symptoms of a U0055 diagnostic trouble code may include:

Faulty or damaged wiring
The engine oil will exhibit dilution from the ECUs attempts to increase engine temperature. Some vehicles advance the fuel injection timing slightly after top center to afterburn a small amount of fuel to increase exhaust temperatures. Some of this fuel enters the crankcase. When the ECU determines the necessity to regenerate the DPF, the service life of the oil be shortened significantly
Poor fuel economy
Rich or lean exhaust

Possible Causes :

Faulty IMRC actuator relay (if equipped)
A large air leak at or near the number one oxygen sensor would also cause a lean mixture.
A large vacuum leak would cause a massive amount of un-metered air to enter the intake manifold resulting in an overly lean mixture.

Repair Processes :

Use the DVOM to test resistance and continuity on all system circuits if actuator and sensor resistance levels are in compliance with manufacturer's specifications. With the valve disconnected, the red voltmeter lead should be attached to the IMRC valve power wire and the black voltmeter lead connected to ground.

Process Tips

Diagnostic trouble code U0055 is not difficult to diagnose and repair. Thus, it always pays to have a qualified technician to look after your vehicle should this error code arise.

Diagnosing this code requires the engine to be in good running shape, without unmetered air entering the engine. If other codes that relates to misfiring condition, lean running or air entering the engine is present, then you must first fix those error codes before U0055.

Fortunately, U0055 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

U0055 Trouble Code For Specific Cars

U0055 Audi Ad ANTI THEFT INPUT SIGNAL SHORT TO GROUND
U0055 Studebaker Commander Lamp Turn Signal Rear Output Circuit Short To Battery
U0055 Adler 14 ABS Inlet Valve Coil RR Circuit Failure
U0055 Spadaconcept Codatronca Lamp Brake Warning Output Circuit Failure
U0055 Rumpler Tropfenwagen Ignition Run Circuit Failure
U0055 Ariel Atom Air Suspension LR Air Spring/Shock Solenoid Output Circuit Short To Ground
U0055 Volkswagen Crosspolo RF LAMP HIGH BEAM CIRCUIT Failure