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Exterior Lighting, Basic Function - GF82.10-P-9900A

Model all (CAR) 

General 

The exterior lights control all the safety and comfort-relevant functions of the front, side and rear lamps on the vehicle.

A differentiation is made between the following headlamp versions depending on the vehicle equipment involved:

For the following special vehicle conditions, the exterior lighting functions are only partly available:

To reduce the load on the on-board electrical system, the energy management requests that the exterior lighting be switched off in certain situations. This helps to avoid the on-board electrical system battery from being discharged.

Substitute light control 

The function of the vehicle's rear lighting is continuously monitored. If the rear turn signal light fails, the corresponding brake light is actuated at flasher frequency as a replacement.

Emergency light system 

A software emergency light function is activated if a data transfer fault occurs. The following light functions are then activated:

If the rain and light sensor fails or if communication with the rain and light sensor fails, the automatic driving lights are activated.

If, on vehicles equipped with LED headlamps, the exterior lighting control unit malfunctions, the headlamp control units activate the low beams (emergency light function). On vehicles equipped with halogen headlamps, the vehicle in this case can no longer be driven. The exterior lighting control unit is the central controller unit or the front central controller unit, depending on the vehicle equipment involved.

On model 118, 177, 247 the brake light is actuated permanently if the Electronic Stability Program malfunctions.

Overview of light functions 

The exterior lighting includes the following light functions:

Various control messages are used to inform the driver about the current operating status of the exterior lighting. In certain situations the driver is also notified acoustically about active functions (e.g. turn signal light).

  Subsystems     
  Actuate standing lights and parking lights, basic function   GF82.10-P-1000A 
  Actuate driving lights, basic function   GF82.10-P-1013A 
  Actuate rear fog light, basic function   GF82.10-P-1021A 
  Actuate brake lights, basic function   GF82.10-P-1022A 
  Actuate turn signal light, basic function   GF82.10-P-1023A 
  Actuate reversing light, basic function   GF82.10-P-1024A 
  Comfort illumination, basic function   GF82.10-P-1025A