B1242 Diagnostic Trouble Code

B1242 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 B1242 diagnostic trouble code may include:

Blown fuse (if applicable)
Engine surge
Reduction in engine performance, especially at low RPM levels
Rich or lean exhaust

Possible Causes :

Faulty IMRC actuator relay (if equipped)
A large air leak at or near the number one oxygen sensor would also cause a lean mixture.
Dirty air cleaner element Damaged DPF

Repair Processes :

If you find a related TSB, the information will often help in diagnosing the code in question as TSBs are crested from many thousands of repairs. Look for missing ground strap or a rusty ground where the fuel tank is grounded to the frame. Check for damage to the wiring harness connector.

Process Tips

Diagnostic trouble code B1242 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 B1242.

Fortunately, B1242 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

B1242 Trouble Code For Specific Cars

B1242 Hillman Speed PATS Received Invalid Format Of Key-Code From Ignition Key Transponder
B1242 Hyundai I10 SCP (J1850) Invalid or Missing Data for Cassette Tape
B1242 Giannini 1000 Oil Change Reset Button Circuit Short To Battery
B1242 Fnm 2150 Left Rear Stop lamp Circuit Short to Battery
B1242 Suzuki Hayabusa Metering Oil Pump Temperature Sensor Circuit Malfunction
B1242 Fiat Talento Left Front Center Sensor Circuit Short to Vbat
B1242 Renault 21