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

Model 463 

as of model year 2013 

Function requirements, general 

IMPORTANT Model 463 (except 463.342)

as of model year 2013 up to model year 2019

Model 463.342

as of model year 2013

The electronic ignition lock control unit (N73) transmits the status of circuit 15 via the interior CAN (CAN B) to the SAM control unit (N10).

IMPORTANT Model 463 (except 463.342)

as of model year 2019

The electronic ignition lock control unit transmits the circuit status of circuit 15 to the rear SAM control unit (N10/8) via the interior CAN. The front SAM control unit (N10/6) also actuates the rear SAM control unit via a direct line (circuit 15) in order to counteract any delayed forwarding of the request via the CAN buses.

The Electronic Stability Program control unit (N30/4) transmits the "Standstill" signal to the rear SAM control unit via the suspension FlexRay (Flex E), electronic ignition lock control unit and interior CAN.

Brake light actuation, general 

The brake light actuation design can be adapted. In the event of emergency braking the brake lights on the vehicles are actuated to flash on and off.

Brake light actuation function sequence 

The brake light actuation is activated when the service brake is operated.

The Electronic Stability Program control unit recognizes the operation of the service brake by evaluating the status of the brake light switch (S9/1).

The brake light switch is supplied with voltage by the Electronic Stability Program control unit via circuit 15. When the brake pedal is being operated, the voltage that is present is switched through to the Electronic Stability Program control unit.

For vehicles as of 03.04.2018 except model 463.342, the following applies: 

The Electronic Stability Program control unit then sends the status of the service brake to the rear SAM control unit and also the trailer recognition control unit (N28/1) via the suspension FlexRay, electronic ignition lock control unit and interior CAN.

The Electronic Stability Program control unit also actuates the rear SAM control unit via a direct line (circuit 54) in order to counteract any delayed forwarding of the request via the CAN buses.

The rear SAM control unit routes this signal via a direct line to the trailer recognition control unit.

The rear SAM control unit actuates the following components:

IMPORTANT Model 463 (except 463.342)

as of model year 2019

with code ZU7 (National version for Canada)

Model 463 (except 463.342)

as of model year 2019

with code ZU8 (National version for USA)

When turn signal light actuation is active, the flasher frequency has higher priority than the brake light.

IMPORTANT When fog light actuation is active, the brake lamp closest to the fog light is not actuated.

The trailer recognition control unit receives the incoming information and actuates the trailer's brake lamps via the trailer socket (X58) (with code Q55 (Trailer coupling, ball head) or code Q59 (Trailer hitch, removable)).

If emergency braking (Brake Assist active or vehicle deceleration a > 7.5 m/s2 ) is initiated at a vehicle speed of v > 25 km/h, in vehicles except code ZU7 (National version Canada) and except code ZU8 (National version USA), the brake lamps and center brake lamp are actuated (and flash).

The Electronic Stability Program control unit transmits information about the vehicle speed and the "Emergency braking" signal via the chassis FlexRay, the electronic ignition lock control unit and the interior CAN to the rear SAM control unit and also to the trailer recognition control unit.

The rear SAM control unit actuates the brake lights and the center brake lamp for the duration of the signal at a frequency of f = 3 to 5 Hz and sends a signal, which defines the period for the configured dark phase, over the interior CAN to the trailer recognition control unit. The trailer recognition control unit then actuates the brake lamps on the trailer via the trailer socket (with code Q55 (Trailer coupling, ball head) or code Q59 (Trailer hitch, removable)).

The following frequencies are output, depending on the light sources used on the trailer:

IMPORTANT If the vehicle comes to a standstill following emergency braking, the hazard warning flasher function is automatically activated if braking occurred from a speed of v > 70 km/h.

The danger braking signal is reset if one of the following preconditions is met:

For vehicles up to 02.04.2018 or model 463.342, the following applies: 

The Electronic Stability Program control unit then sends the status of the service brake to the SAM control unit and the trailer recognition control unit (except model 463.242) via suspension CAN 1 (CAN E1), electronic ignition lock control unit and interior CAN.

The Electronic Stability Program control unit also actuates the SAM control unit via a direct line (circuit 54) in order to counteract the forwarding of the request via the CAN buses being delayed.

The SAM control unit forwards this signal to the trailer recognition control unit (except model 463.242) via a direct line.

The SAM control unit actuates the following components:

The trailer recognition control unit (except model 463.242) receives the service brake status and actuates the trailer brake lamps via the trailer socket (except model 463.242) an.

If, at a vehicle speed of v > 25 km/h, emergency braking (Brake Assist active or vehicle deceleration a > 7.5 m/s2 ) is initiated, then the brake lights and the center brake lamp are actuated to flash on and off.

The instrument cluster (A1) transmits the vehicle speed via the interior CAN to the SAM control unit. The Electronic Stability Program control unit sends the "Emergency braking" signal via chassis CAN 1, electronic ignition lock control unit and interior CAN to the SAM control unit and to the trailer recognition control unit (except model 463.242). The SAM control unit actuates the brake lamps and center brake lamp for the duration of the signal at a frequency of f = 3 up to 5 Hz and transmits a signal, which defines the period for the configured dark phase, to the trailer recognition control unit (except model 463.242) via the interior CAN.

The following frequencies are output according to the light sources used on the trailer:

IMPORTANT If the vehicle comes to a standstill following emergency braking, the hazard warning flasher function is automatically activated if braking occurred from a speed of v > 70 km/h.

The Electronic Stability Program control unit resets the emergency braking signal if one of the following requirements is met:

  Electrical function schematic for brake light actuation Model 463 (except 463.342) as of model year 2013 up to model year 2019Model 463.342 as of model year 2013 PE82.10-P-2057-97ZGA
    Model 463 (except 463.342) as of model year 2019 PE82.10-P-2057-97ZGB
  Overview of exterior lights system components   GF82.10-P-9998GW