C0612 BMW Fault Code

Description:

The Transmission Fluid Pressure Switch allows the engine's control module (PCM) or Transmission Control Module (TCM) to use hydraulic fluid to engage the clutches in the transmission to allow for smoother shifting while driving. If the PCM or TCM detects an issue with the hydraulic clutch or the pressure switch, the BMW PCM or TCM will set code C0612

C0612 Code Symptoms :

The original multi-displacement system turned off opposite pairs of cylinders, allowing the engine to have three different configurations and displacements. C0612 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 C0612

C0612 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 C0612 code ?

• Exhaust tube
• Faulty starter motor
• Faulty Mass Air Flow (MAF) sensor
• Open or short in the CMP sensor circuits

One example of this would be when an bmw automatic car in placed in gear. To prevent the added drag from the torque converter and transmission from reducing the idling speed, the PCM will command the idle control valve to allow more air to enter the engine, while at the same time, adjusting the injector pulse width to inject more fuel to suit the increased amount of air. Note that the idle air control valve is closed by the PCM when the throttle plate is opened to prevent excess air from entering the engine.