B1284 Diagnostic Trouble Code

B1284 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 B1284 diagnostic trouble code may include:

Cherry red hot catalytic converter
Poor acceleration
The light may stay on or light intermittently as the DPF regenerates. The engine will be sluggish on acceleration.
Hesitation upon acceleration

Possible Causes :

Some aftermarket accessories and performance modifications
A faulty oxygen sensor. This will set a code in itself, however, a faulty oxygen sensor does not automatically condemn the sensor. The code just means that the sensor signal was not within specifications. An air leak or any of the above will cause an erroneous signal. There is a multitude of O2 codes relating to O2 performance which gives a clue to the problematic area.
An air leak forward of the DPF will change the sensor readings resulting in the code

Repair Processes :

If the engine displays a miss and there wasn't a code, determine which cylinder is misfiring. If the exhaust manifold is visible, spay or pour a small amount of water on each cylinder exhaust port. Water will evaporate immediately on good cylinders and slowly on the missing cylinder. If this can't be accomplished pull the plugs and check the condition. 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. If the scan tool has that capability, and the scan tool can operate the IMRC valves, then the problem is either resolved and a simple code clearing is all that's left or a new PCM would be called for.

Process Tips

Diagnostic trouble code B1284 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 B1284.

Fortunately, B1284 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

B1284 Trouble Code For Specific Cars

B1284 Toyota Super Passenger Door Disarm Switch ckt Short to Ground
B1284 Chevrolet Grand Blazer Dual Alternator Lower Circuit Malfunction/ Manifold Absolute Pressure (MAP) Sensor Circuit Intermittent Low Voltage
B1284 Chevrolet Tahoe Electronic Throttle Monitor Data Available
B1284 Fiat Premio Lamp Turn Signal Right Circuit Short To Ground
B1284 Porsche 996 Fuel Level Sensor Circuit Range/Performance
B1284 Pininfarina Rosso Evap Emission Control Sys Vent Control Valve Circuit
B1284 Mazda Axela Ii Transmission Transfer Case Counter Clockwise Shift Relay Coil Circuit Failure