U2151 Diagnostic Trouble Code

U2151 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 U2151 diagnostic trouble code may include:

The light may stay on or light intermittently as the DPF regenerates. The engine will be sluggish on acceleration.
Faulty PCM
If the DPF is not cleared the ECU will revert to the "Limp Home Mode" until the situation is corrected
Diminished fuel efficiency

Possible Causes :

An air leak forward of the DPF will change the sensor readings resulting in the code
Rusty exhaust systems, cracked exhaust manifolds or damaged or missing gaskets or donuts will cause air leaks.
Fuel with a large percentage of sulfur will clog the DPF quickly

Repair Processes :

Check to make sure they are not burnt or corroded. If in doubt, get some Electrical Contact cleaner at any parts store if cleaning of the terminals is needed. 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 U2151 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 U2151.

Fortunately, U2151 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

U2151 Trouble Code For Specific Cars

U2151 Morris Ten Four Cam Calibration Fault
U2151 Fiat Dino Lamp Keypad Output Short Circuit To Ground
U2151 Alvis Te Air Suspension Disable Switch Circuit Short To Ground
U2151 Chevrolet Vega Engine Coolant Temperature (ECT) Sensor Circuit Intermittent High Voltage/IAT - B Circuit High Input
U2151 Holden Vt Pressure Control Solenoid "B" Short Circuit
U2151 Toyota Proace Park Brake Actuator Assembly Switch Released Circuit Short to Gnd
U2151 Mitsubishi 380 Audio CD/DJ Internal Fault