Brake Lamp: Description and Operation

GF82.10-P-3010RTE Stop Lamp Actuation, Function

Component Identification:

General brake light actuation function sequence
The brake light actuation is comprised of several subfunctions.
These are:
^ Static brake light actuation
^ Flashing brake light actuation (adaptive brake lights)

Static brake light actuation

Function requirements:
^ Circuit 15 On

Static brake light actuation function sequence
The operation of the service brake is recognized by the BAS release switch (A7/7s1) at the BAS brake booster and transmitted to the ESP control unit.

The ESP control unit transmits this message via CAN-C to the central gateway control unit, which routes the signal to CAN-B and forwards it to the rear SAM control unit. The rear SAM control unit receives this signal redundantly via circuit 54 directly from the ESP control unit.

Depending on the equipment fitted, the rear SAM control unit actuates the following components:
^ Brake lights, taillights, parking lights and side-marker lamp
^ Center high-mounted stop lamp
^ Left and right brake lights on the trailer (for code (550) Trailer hitch)

Flashing brake light actuation (adaptive brake lights)

Function requirements
^ Circuit 15 On
^ Brake applied
^ Hazard warning flashing not active
^ Vehicle speed v > 50 km/h and
- Brake Assist active or
- Vehicle deceleration a > 7.5 m/s2

Function sequence for flashing brake light actuation (adaptive brake lights)
The vehicle deceleration and the speed (rpm sensor signals) are determined by the ESP control unit.

In the event of an emergency stop, the ESP control unit sends a corresponding signal to CAN-C. This is routed to CAN-B via the central gateway control unit and received by the rear SAM control unit.
For the duration of the signal (t > 1 s), the rear SAM control unit actuates the following components at a frequency of f = 5 Hz:
^ Left and right stop lamp, taillamp, parking lamp and side-marker lamps
^ Center high-mounted stop lamp

The emergency stop signal is reset if one of the following preconditions is fulfilled:
^ Brake released
^ C. 15 OFF
^ Vehicle speed v < 5 km/h
^ Brake Assist not active and vehicle deceleration a < 6.5 m/s2