GF82.10-P-3010RC Brake Light Actuation, Function

GF82.10-P-3010RC Brake Light Actuation, Function

Function requirements for brake light actuation in general
^ Circuit 15 On

Brake light actuation, general
Corresponding to the request the brake light actuation realizes a static or flashing actuation of the brake lights on the vehicle.

Brake light actuation is comprised of the following subfunctions:
^ Function sequence, static brake lights
^ Function sequence, adaptive brake lights

Function sequence, static brake lights
The EIS [EZS] control unit (N73) sends the circuit 15 status to the interior CAN.
Operation of the service brake is detected by the BAS release switch (A7/7s1). The ESP and BAS control unit (N47-5) reads in the status of the BAS release switch and transmits the brake light actuation request over the engine compartment CAN to the central gateway control unit (N93). The central gateway control unit provides it to the rear SAM control unit with fuse and relay module (N10/2) on the interior CAN. The ESP and BAS control unit actuates the rear SAM control unit over a direct line (circuit 54), to counteract any delay in the forwarding of the request over the two data buses.

The rear SAM control unit receives the request and actuates the following components:
- Left brake light, taillight and parking light (E3e9)
- Right brake light, taillight and parking light (E4e9)
- Center high-mounted brake lamp (E21)

Additional function requirements, adaptive brake lights
^ Vehicle speed v > 25 km/h
^ Brake Assist system active or vehicle deceleration a > 7.5 m/s2
^ Manual hazard warning flashing inactive

Function sequence, adaptive brake lights
The vehicle speed and deceleration are determined by the ESP and BAS control unit.
In the event of an emergency braking maneuver the ESP and BAS control unit sends a corresponding signal to the engine compartment CAN.
The central gateway control unit provides it to the rear SAM control unit on the interior CAN. The rear SAM control unit then actuates the brake lights and the center high-mounted brake lamp to match the duration of the signal (t ≥1 s) at a frequency of f = 2 to 7 Hz.

If the vehicle comes to a standstill, the hazard warning flasher function is activated automatically.

The danger braking signal is reset if one of the following preconditions is met:
- Vehicle speed v < 10 km/h
- Vehicle deceleration a < 6.5 m/s2