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B129C BMW Fault Code

Check B129C 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.

B129C Code Symptoms :

See B129C in engine

There are currently two main types of cylinder deactivation used today, depending on the type of engine. B129C code for the pushrod design which uses solenoids to alter the oil pressure delivered to the lifters. In their collapsed state, the lifters are unable to elevate their companion pushrods under the valve rocker arms, resulting in valves that cannot be actuated and remain closed.

Diagnosis And Repairing B129C

B129C OBD2 specifically refers to the camshaft (cam) timing. In this case, if the cam timing is over-retarded, the engine light will be illluminated and the code will be set.

How to fix B129C code ?

See B129C repair manual
  • Exhaust gas leaks
  • Exhaust gas leaks
  • Incorrect Positive Crankcase Ventilation (PCV) hose connection
  • Faulty Intake Valve Timing Control Solenoid Valve

Gear changes are accomplished by a command from the BMW TCM to energize the clutch actuator to release the clutch; after which various actuators inside the transmission disengage the current gear, and depending on current operating conditions, engage the next higher or lower gear ratio. All of this happens much faster than a human driver could change gears, and in most applications, gear changes are as smooth and seamless as on any fully automatic transmission.

BMW Cars that meet B129C error