B3959 BMW Fault Code

Description:

Brake Switch Circuit Input Malfunction Indicates PCM did not receive a brake pedal position (BPP) input. Open or short in BPP circuit Open or short in stoplamp circuits damaged PCM Malfunction in module(s) connected to BPP circuit.

(Rear Electronic Module [REM] Windstar and LS6/LS8 or Lighting Control Module (LCM) Continental and Town Car. Damaged brake switch Misadjusted brake switch Check for proper function of stoplamps.

B3959 Code Symptoms :

When you turn on the ignition, the Service Engine Soon or Check Engine B3959 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 B3959!

Diagnosis And Repairing B3959

B3959 OBD 2 code on vehicles with electronically controlled automatic transmissions, the 3-4 shift solenoid is responsible for actuating the hydraulic circuits to activate clutches or bands that change gears inside the automatic transmission.

How to fix B3959 code ?

• Damaged ECM
• Faulty Camshaft Position Sensor
• Failures of clutch motion/travel sensors.
• Incorrect Positive Crankcase Ventilation (PCV) hose connection

Some systems require that the actuator has an adequate supply of brake fluid. Low brake fluid levels can mimic the symptoms of code B3959, so consult the manual to locate the brake fluid reservoir.

Bear in mind that a low fluid level can set code B3959 on some applications, so make sure that on fluid operated systems the fluid level is up to the mark before starting an electrical diagnosis.