P12BB Diagnostic Trouble Code

P12BB is a kind of OBD-II Diagnostic P-Powertrain 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 P12BB diagnostic trouble code may include:

Faulty O2 Sensor
Lack of power
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 :

A large air leak at or near the number one oxygen sensor would also cause a lean mixture.
Faulty IMRC actuator relay (if equipped)
Fuel with a large percentage of sulfur will clog the DPF quickly

Repair Processes :

It should be pretty close to battery voltage (12 volts). If not, then this is the circuit that has the problem. 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. Oxygen sensors signal the engine management computer the amount of oxygen present in the exhaust, which is used in determining and controlling the fuel ratio.

Process Tips

Diagnostic trouble code P12BB 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 P12BB.

Fortunately, P12BB is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

P12BB Trouble Code For Specific Cars

P12BB Spa 25 Hp Lamp Backup Switch Input Circuit Short To Ground
P12BB Ford Tonka Mirror Switch Assembly Circuit Short to Battery
P12BB Triumph Vitesse Pedal Demand Sensor B Circuit High Input
P12BB Sunbeam Alpine Manifold Absolute Pressure/Barometric Pressure Circuit Range/Performance Problem
P12BB Ford Ecosport Mass or Volume Air flow Circuit High Input
P12BB Toyota Vista Passenger Seat Occupant Detection Circuit Open
P12BB Fiat Panda 2 Lamp Turn Signal Right Circuit Open