B2439 Diagnostic Trouble Code

B2439 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 B2439 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 :

Look for rubbing, scraping, bare wires, worn spots or melted plastic connectors. Pull the connectors apart and carefully look at the terminals (the metal parts) inside the connectors. 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. Replace the oxygen sensor that is downstream from the catalytic converter on the side of the engine that does not contain cylinder #1. Also, if a oxygen sensor code stating "heater circuit malfunction" the sensor has most probably failed.

Process Tips

Diagnostic trouble code B2439 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 B2439.

Fortunately, B2439 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

B2439 Trouble Code For Specific Cars

B2439 Lifan 620 Throttle Control Unit Modulated Command Malfunction
B2439 Saturn Sl Incorrect Module Design Level
B2439 Fiat Siena Led #1 Circuit Failure
B2439 Subaru Outback LF LAMP HIGH BEAM CIRCUIT Short to Battery
B2439 Ford Zodiac Motor Relay # 1 Circuit Short to Battery
B2439 Aston Martin Db5 Air Suspension RR Air Spring/Shock Solenoid Output Circuit Short To Ground
B2439 Geely Bo O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 3)