Functional description

The oil pressure indicator light lights up if the oil pressure does not exceed a value defined by a spring. This value is approx. 0.2 to 0.5 bar. If the engine is started, the oil pressure opens the earth contact and the oil pressure indicator light goes out. The oil pressure switch is connected to the engine control system across a signal cable. The data interchange is digital.

Fig 1: Identifying Oil Pressure Switch Components

Courtesy of BMW OF NORTH AMERICA, INC.