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B3439 BMW Fault Code

Check B3439 OBD Fault Code Reason
Description:

Intake Manifold Runner Control Malfunction (Stuck Open) The IMRC system is monitored for failure during continuous, key ON engine OFF or key ON engine running self-test. The test fails when the signal on the monitor pin is less than an expected calibrated range at closed throttle. IMRC monitor signal circuit shorted to BMW PWR GND or SIG RTN Damaged IMRC actuator Damaged PCM An IMRCM PID reading approximately near 1 volt at closed throttle may indicate a fault.

B3439 Code Symptoms :

See B3439 in engine

When you turn on the ignition, the Service Engine Soon or Check Engine B3439 light should flash briefly, indicating that the OBD system is ready to scan your vehicle for any malfunctions. After this brief flash, the light should stay off while you drive as long as no problems are detected. If so, you'll be glad to know that your vehicle is equipped with an early warning system that could save you time, money, and fuel in addition to helping protect the B3439!

Diagnosis And Repairing B3439

B3439 OBD2 reports a sensor fault, replacement of the sensor is unlikely to resolve the underlying problem. The fault is most likely to be caused by the systems that the sensor is monitoring, but might even be caused by the wiring to the sensor itself.

How to fix B3439 code ?

See B3439 repair manual
  • EVAP canister or fuel tank leaks
  • Camshaft Position Sensor harness is open or shorted
  • Faulty variable valve timing (VVT)
  • Intake Valve Timing Control Solenoid Valve circuit poor electrical connection

At this point we are assuming that the fuses and relays are good. You will need to locate the PCM/TCM and the power input signal circuit using your vehicle information source.

Unplug the connector from the PCM/TCM, place the ignition switch in the ON position, and probe the appropriate circuit with the positive test lead of the DVOM.

BMW Cars that meet B3439 error