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Brake Light Switch Signal




Brake-Light/Brake-Test Switches

Two switches are fitted on the brake pedal which supply the following signals:
- S_BLS (Brake-Light Switch)
- S_BLTS (Brake-Light Test Switch)

The DME control module evaluates the signals for the purpose of registering brake operation.

Function
- Model series E38, E39, E46, E53, E6x, E8x:
The brake-light switch connects to ground (B-), the brake-light test switch connects to B+.
- Model series E36/7 (Z3):
The brake-light switch and the brake-light test switch connect to B+.

Both signals are checked for plausibility.

The following tables show (depending on the model series) how the status of the brake-light switch/brake-light test switch performs:












Troubleshooting
If the signals are not plausible in relation to one another, a fault code is stored in the DME control module. Cruise control is deactivated as a result of this fault memory entry.