Logo

B0508 BMW Fault Code

Check B0508 OBD Fault Code Reason
Description:

The Camshaft Position sensor will signal the Engine Control Module when the #1 cylinder is ready for the spark plug to fire (top-dead-center on compression stroke).

The ECM uses the information from this sensor to help calculate fuel delivery and spark timing.

B0508 Code Symptoms :

See B0508 in engine

The original multi-displacement system turned off opposite pairs of cylinders, allowing the engine to have three different configurations and displacements. B0508 code had an elaborate diagnostics procedure, including showing engine trouble codes on the air conditionning display. However, the system was troublesome, misunderstood by customers, and a rash of unpredictable failures led to the technology being quickly retired.

Diagnosis And Repairing B0508

B0508 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 B0508 code ?

See B0508 repair manual
  • Exhaust gas leaks
  • EVAP system hose leaking
  • Failures of clutch motion/travel sensors.
  • Variable Valve Timing (VVT) circuit is open or shorted

Some systems require that the actuator has an adequate supply of brake fluid. Low brake fluid levels can mimic the symptoms of code B0508, so consult the manual to locate the brake fluid reservoir.

Bear in mind that a low fluid level can set code B0508 on some applications, so make sure that on fluid operated systems the fluid level is up to the mark before starting an electrical diagnosis.

BMW Cars that meet B0508 error