Brake light switch

WARNING: This page does not describe the selected car, but rather 45 other vehicles, including the 2016 BMW M5, 2016 BMW 550i xDrive, 2016 BMW 550i, 2016 BMW 535i xDrive, and 2016 BMW 535i. However, it is still accessible from the selected car via links, so may be relevant.

Together with the signal from the brake pressure sensor, braking operations are detected. Two Hall effect sensors as switches are installed in the brake light switch: the brake light switch and the brake light test switch (redundancy for safety reasons). The signals indicate whether the brake pedal has been pressed. The data interchange is digital.

Fig 1: Identifying Brake Light Switch

Courtesy of BMW OF NORTH AMERICA, INC.

Item	Explanation
1	Brake light switch
2	4-pin plug connection

The two redundant signals from the brake light switch are read in by the Car Access System (CAS). The CAS relays the signals to systems such as the Dynamic Stability Control (DSC) and for the engine-management control unit via the bus system. A signal from the brake-light switch is still hard-wired to the footwell module (FRM).

NOTE: Observe the electrical connection!

Depending on the vehicle, the brake light switch from the Front Electronic Module (FEM) is read in. Observe the wiring diagrams in the diagnosis!