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GF82.10-P-2009CW Headlamp Control, Function



GF82.10-P-2009CW Headlamp Control, Function
- except CODE (614) Bi-xenon headlamp unit
- except CODE (622) Intelligent Light System (right-hand traffic)


General driving light actuation function sequence

The driving light actuation consists of several subfunctions. These are:
^ Low beam actuation
^ High-beams actuation
^ Daytime running lamps actuation
^ Automatic driving lights on

Low beam actuation

Function requirements

^ Circuit 30
^ Exterior lights switch (S1) to manual driving lights position (third notch to right)

Low beam actuation function sequence
Low beam actuation function sequence The position of the exterior lights switch is read in via the instrument panel LIN by the front SAM control unit with fuse and relay module (N10/1). As a result of this the front SAM control unit actuates the left low beam (E1e2) and right low beam (E2e2).

High-beams actuation

Function requirements

^ for high beam function, circuit 15R and low beam On
^ for headlamp flasher function, circuit 15R On

Function sequence for high beams
High beam actuation is requested by pushing the combination switch (S4) forward.

The steering column tube module control unit (N80) detects the position of the combination switch and transmits the request to the front SAM control unit via the chassis CAN.
The front SAM control unit actuates the left high beam (E1e1) and the right high beam (E2e1).

Headlamp flasher function sequence
To activate the headlamp flasher, the combination switch must be pulled backwards. The high beam is actuated for as long as the combination switch is held in position.
The function sequence and the signal flow of the headlamp flasher function is the same as for the high beams function.

Feedback
Active high beam/headlamp flasher actuation is transmitted to the instrument cluster (A1) by the front SAM control unit via the interior CAN. This then actuates the high beam indicator lamp (A1e3).

Daytime running lamps actuation

Function requirements

^ Function activated via the instrument cluster (country specific)
^ Circuit 61 ON

Daytime running lights actuation function sequence
The daytime running lamps function is activated by the front SAM control unit. The front SAM control unit actuates the left low beam and the right low beam.

In countries with statutory daytime running lamp regulations, only the headlamp flasher is permitted in daytime running lamp mode, but not the high beam.

Automatic headlamp actuation

Function requirements

^ Exterior lights switch in "Auto" position
^ Light sensor (B38/1) (without code (345) Rain sensor) or rain/light sensor (B38/2) (with code (345) Rain sensor) signaling darkness

Auto on/off headlamps function sequence

Function at start of journey (in darkness)

The standing lights are activated as of circuit 15R On. The low beams are also activated with circuit 61 On. It is possible then to switch on the high beams.

Function at end of journey (in darkness)
The low beams (high beams, if necessary) are deactivated when the engine is switched off. The standing lights are not switched off until the transmitter key (A8/1) is removed from the electronic ignition lock control unit (N73).

Function while driving
The light sensor or the rain/light sensor detects the ambient brightness. When darkness is detected, the relevant request is forwarded to the front SAM control unit via the wiper/inside rearview mirror LIN. The front SAM control unit actuates the left low beam and the right low beam.

Function at wiper startup:
When the wiper system is actuated for t = 20 s with a wipe cycle period of t < 6 s, the front SAM control unit actuates the left and right low beams.

If there is no wipe cycle for t = 60 s, the driving lights are switched off.