Brake Lamp: Description and Operation

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

Component Identification:

Stop lamp actuation
Function requirements
^ Circuit 15 ON

Function
By applying the service brake, voltage is applied over the switching contacts in the stop lamp switch to the ESP control unit, which then transmits the "Stop lamp On" signal over CAN-C to the central gateway control unit. The central gateway control unit then makes it available to the rear SAM control unit over CAN-B. At the same time, the ESP control unit forwards the "Stop lamp On" (circuit 54) signal directly to the rear SAM control unit.

The direct actuation is aimed at counteracting a possibly delayed forwarding of the request triggered by the stop lamp switch over CAN-C and CAN-B.

The rear SAM control unit directly actuates the stop lamps, the center high-mounted stop lamp and, for vehicles with code (550) Trailer hitch, the trailer connection unit [AAG] control unit (circuit 54).

Stop lamps with code (954) Avantgarde are no longer designed as a light emitting diode (LED) light source. The center high-mounted stop lamp will continue to be designed as an LED light source.

For vehicles with code (550) Trailer hitch, the trailer connection unit [AAG] control unit actuates the AHV socket accordingly.

Stop lamp actuation flashing on and off (emergency braking signal)

Function requirements
^ Brake actuated
^ Vehicle speed > 50 km/h
^ Brake Assist System active or vehicle deceleration > 7.5 m/s2

Function
In the event of an emergency stop, the ESP control unit generates a corresponding signal on CAN-C.
The central gateway control unit forwards this over CAN-B to the rear SAM control unit. The rear SAM control unit actuates the stop lamps and the center high-mounted stop lamp with a flashing frequency of 5 Hz for the duration of the signal (min. 1 s).

Once the vehicle has come to a standstill, the stop lamps and the center high-mounted stop lamp are actuated permanently again. Additionally, the automatic hazard warning flashing function is activated.

The emergency braking signal is reset, when one of the following conditions is complied with:
- Brake not actuated
- Vehicle speed < 10 km/h
- Brake Assist System inactive and vehicle deceleration < 6.5 m/s2 for min. 150 ms