The plausibility of the signal from the oil-pressure switch is checked in the engine management system. To this end, the signal of the oil-pressure switch is analysed after the engine is stopped. After a certain time, the oil-pressure switch must not detect oil pressure. If oil pressure is still detected after turning off the engine, a fault is entered.
In the S54 engine, exclusively the fault 2F7B is treated. This is set if the signal is implausible. Possible error causes are wire faults or a defective component.