B1249 Diagnostic Trouble Code

B1249 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 B1249 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
If the DPF is not cleared the ECU will revert to the "Limp Home Mode" until the situation is corrected

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)
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 :

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 B1249 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 B1249.

Fortunately, B1249 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

B1249 Trouble Code For Specific Cars

B1249 Isuzu Unicab
B1249 Sbarro Issima Injection Pump Fuel Metering Control "A" Intermittent (Cam/Rotor/Injector)
B1249 Mazda Spiano A/C Compressor Temperature Sensor Malfunction
B1249 Alvis Silver Eagle Air Conditioner Refrigerant Charge Loss
B1249 Alvis Te Air Suspension Disable Switch Circuit Short To Ground
B1249 Mercury Lynx Air Suspension LR Height Sensor Circuit Open
B1249 Smart Fortwo Lamp Air Bag Warning Indicator Circuit Open