Stop lamp actuation, function - GF82.10-P-3010SX
MODEL 216.3, 221.0/1 up to Model Year 8
Illustrated on model 221
Stop lamp actuation
Function requirement
- Circuit 15 ON
Function
Actuation of the service brake is detected by the BAS release switch (A7/7s1) in the BAS brake booster. This is read in by the ESP control unit.
The ESP control unit transmits the "brake lights On" request over the chassis CAN to the central gateway control unit. The request is sent by the central gateway control unit over the interior CAN to the rear SAM control unit.
At the same time, the "brake lights On" request (circuit 54) is forwarded by the ESP control unit directly to the front SAM control unit. Once there however, it is only looped through and forwarded to the rear SAM control unit. The rear SAM control unit actuates the brake lights and the center high-mounted stop lamp.
The direct actuation is to counteract any delay in forwarding the "brake lights On" request over the chassis CAN and the interior CAN.
The brake lights and the center high-mounted stop lamp are also actuated if the electric parking brake switch (S76/15) is operated while driving.
Vehicles with code (550) Trailer hitch
The "brake lights On" request is forwarded by the central gateway control unit over the interior CAN to the trailer recognition control unit.
At the same time, the rear SAM control unit forwards the "brake lights On" signal (circuit 54) directly to the trailer recognition control unit which applies the "brake lights On" request to the trailer hitch socket.
Flashing brake lights actuation (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 the chassis CAN. The central gateway control unit forwards this over the interior CAN to the rear SAM control unit. The rear SAM control unit actuates the brake lights 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 stop, the brake lights and the center high-mounted stop lamp are constantly actuated again. In addition, the automatic hazard warning flasher function is activated.
The emergency braking signal is reset if one of the following requirements is fulfilled:
- Brake not actuated
- Vehicle speed <10 km/h
- Brake Assist System not active and
- Vehicle deceleration < 6.5 m/s2 for min. 150 ms
| BAS brake booster, component description | A7/7 | GF42.31-P-4004SX | |
| Driver-side SAM control unit with fuse and relay module, component description | N10/1 | GF54.21-P-6010SX | |
| Rear SAM control unit with fuse and relay module, component description | N10/2 | GF54.21-P-6030SX | |
| Trailer recognition control unit component description | N28/1 Model 221 with code (550) Trailer hitch |
GF31.19-P-4050SX | |
| Description of components in ESP control unit | N47-5 | GF42.45-P-5118SX | |
| Electronic ignition/starter switch control unit (EIS) component description | N73 | GF80.57-P-6000SX | |
| Central gateway control unit, component description | N93 | GF54.21-P-4170SX |