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Brake Light Switch, Basic Function - GF42.10-P-2001A

Model All (4xWD, CAR) 

G16166933Courtesy of MERCEDES-BENZ USA

Example illustration of brake light switch 

Overview 

This document contains information on:

General 

The brake light switch (1) sends a signal to the brake lights via actuation of the brake pedal and also sends the position of the brake pedal as a signal to different electronic systems, e.g. Brake Assist System (BAS), anti-slip control (ASR), ESP®. The brake light switch (1) is located to the left of the brake pedal.

The brake light switch (1) fulfills the following functions:

Function 

The brake light switch (1) consists of a shaft with ring magnet. The ring magnet rotates in a printed circuit board with stator in two fixed Hall elements. This produces a change in the voltage. The information about the brake pedal position is routed in the form of two signal voltages to the ESP® control unit, among other things.

When the driver presses the brake pedal, the electric circuit to the brake lamps is closed and the brake light switch (1) switches on the current supply to the brake lights. As soon as the driver takes their foot off the brake pedal, the power is switched off again so that the brake lamps are no longer active. The position of the brake pedal is determined based on the voltage measured by the brake light switch (1). If the vehicle is equipped with a speed control regulator (cruise control), the brake light switch (1) also deactivates the speed control regulator when the brake pedal is pressed.

  Component descriptions     
  Pedal angle sensor, component description Model 223 GF42.22-P-1005A
    Model 243 GF42.22-P-1005B
    Model 206 GF42.22-P-1005C
    Model 232 GF42.22-P-1005F
    Model 254 GF42.22-P-1005H
    Model 214 GF42.22-P-1005K
    Model 118, 177, 247
as of model year 2023
GF42.22-P-1005L
    Model 167
as of model year 2023
GF42.22-P-1005M