B105B Diagnostic Trouble Code

B105B is a kind of OBD-II Diagnostic B-Body 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 B105B 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
Diminished fuel efficiency

Possible Causes :

The Mass Airflow sensor is a hot wire that senses the volume of air entering the intake manifold. The computer uses this information to control fuel mixture.
Defective ECU strategies or components will prevent proper regeneration
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 :

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. It should be pretty close to battery voltage (12 volts). If not, then this is the circuit that has the problem.

Process Tips

Diagnostic trouble code B105B 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 B105B.

Fortunately, B105B is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

B105B Trouble Code For Specific Cars

B105B Lotus Europa Traction Control Motor Circuit Open
B105B Skoda 430 Keyless Entry Circuit Failure
B105B Farbio Gts Injector Circuit Open / Shorted - Cylinder #2
B105B Volkswagen Ecoracer RF PARK LAMP OUTPUT CIRCUIT Short to Battery
B105B Porsche 928 Fuel Delivery System Malfunction - Low
B105B Lamborghini Islero Shift/Timing Solenoid Range/Performance
B105B Opel Zafira C Door Lock Cylinder Circuit Short To Ground