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Headlamp control, function - GF82.10-P-2009CE

MODEL 204.0 /2 except CODE (614) Bi-xenon headlamp unit except CODE (615) Bi-xenon headlamp unit with integrated curve illumination except CODE (616) Bi-xenon headlamp unit with integrated asymmetric curve illumination except CODE (618) Bi-xenon headlamps except CODE (621) Intelligent light system (left-hand traffic) except CODE (622) Intelligent light system (right-hand traffic) as of model year 2009 /YoM 08 

MODEL 204.3 except CODE (615) Bi-xenon headlamp unit with integrated curve illumination except CODE (616) Bi-xenon headlamp unit with integrated asymmetric curve illumination except CODE (621) Intelligent Light System (left-hand traffic) except CODE (622) Intelligent Light System (right-hand traffic) 

MODEL 204.9 except CODE (615) Bi-xenon headlamp unit with integrated curve illumination except CODE (621) Intelligent Light System (left-hand traffic) except CODE (622) Intelligent Light System (right-hand traffic) 

Function requirements, general 

Driving lights actuation, general 

Driving lights actuation includes all functions which serve the optimum illumination of the road while driving.

During driving lights actuation, the standing lights actuation is active; this is described in the "Standing/parking lights actuation, function" document.

The driving lights actuation function is comprised of the following subfunctions:

IMPORTANT The driving lights are actuated corresponding to the position of the exterior lights switch (S1). The status of the exterior lights switch is read by the front SAM control unit with fuse and relay module (N10/1) on vehicles up to 31.5.10 via instrument panel LIN (LIN 1) and directly (voltage-coded) on vehicles as of 1.6.10.

Additional low beams actuation function requirements 

Low beam actuation function sequence 

Turning the exterior lights switch to the "manual driving lights" position requests actuation of the low beams.

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

The front SAM control unit reads in the status of the exterior lights switch and actuates the left low beam (E1e2) as well as the right low beam (E2e2).

It additionally transmits the request "Low beams indicator lamp On" via interior CAN to the instrument cluster (A1), which then actuates the low beams indicator lamp (A1e67).

Additional function requirements, high beam actuation 

High beam actuation function sequence 

The high beams actuation is comprised of the following subfunctions:

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) directly reads in the position of the combination switch and transmits it to the front SAM control unit via the chassis CAN (CAN E).

The front SAM control unit receives the switch position of the combination switch, uses it to generate the request "High beams On", transmits it via interior CAN to the instrument cluster and actuates the left high beams (E1e1) and the right high beams (E2e1). The instrument cluster actuates the high beam indicator lamp (A1e3).

Headlamp flasher function sequence 

The function sequence and signal path for the headlamp flasher function correspond to that of the high beam function. However, to request the headlamp flasher function, the combination switch must be pulled backward. If the combination switch is pulled back and held, the high beam actuation is active for maximum t = 30 s. Then the pending request is interpreted as a "stuck combination switch".

IMPORTANT In vehicles with code (460) Canada version or code (494) USA version, the high beams may not be actuated at the same time as the left front fog lamp (E5/1) and the right front fog lamp (E5/2).

The current incoming request has priority.

Additional function requirements, daytime running lights actuation 

Daytime running lights actuation function sequence 

The instrument cluster sends the request "Daytime running lights On" depending on the country coding or if the daytime running lights request was manually activated in the menu "Settings", "Light" via interior CAN.

The CDI control unit (N3/9) (with diesel engine) or the ME-SFI [ME] control unit (N3/10) (with gasoline engine) sends the engine speed and the circuit 61 status or the "PT_Rdy" signal over the chassis CAN.

The instrument cluster sends the vehicle speed via interior CAN. The front SAM control unit reads in all the relevant information and on model 204.0/2 up to 28.2.11, model 204.9 it actuates the low beams.

With model 204.0/2 as of 1.3.11 or model 204.3 the front SAM control unit actuates the left daytime running lights headlamp (E1/3) and the right daytime running lights headlamp (E2/3).

In vehicles with code (460) Canada version or code (494) USA version, the low beams are actuated in accordance with the data of the light sensor (B38/1) (without code (345) Rain sensor) or the rain/light sensor (B38/2) (with code (345) Rain sensor).

If it is dark, the front SAM control unit actuates both the low beams and the standing lights.

During the day the low beam lights are actuated at reduced power. The parking lights are not actuated.

The light sensor or the rain/light sensor detects the ambient brightness. The front SAM control unit reads in the data from the light sensor or the rain/light sensor via the wiper/inside rearview mirror LIN (LIN 2).

The low beam actuation is deactivated as soon as the exterior lights switch is turned to position "Standing lights", "Manual driving lights" or "Left parking light" or "Right parking light" (as of 1.6.10).

On vehicles with code (460) Canada version, the low beams are switched off after a time interval of t = 3 min. when the vehicle is standing still. When the vehicle then starts to move again, the front SAM control unit automatically activates low beam lights actuation.

IMPORTANT The daytime running lights have a higher priority than the auto on/off headlamps.

In countries with legal daytime running light requirements, only the headlamp flasher is permissible but not the high beams. High beams are only permissible when the driving lights are manually switched on via the exterior lights switch (without code (460) Canada version and without code (494) USA version).

Additional function requirements, auto on/off headlamps 

IMPORTANT The CDI control unit or ME-SFI [ME] control unit sends the engine RPM and the status of circuit 61 or the "PT_Rdy" signal over the chassis CAN. The vehicle speed is sent by the instrument cluster over the interior CAN. The status of the exterior lights switch is read in by the front SAM control unit. The front SAM control unit reads in the data from the light sensor or the rain/light sensor over the wiper/inside rearview mirror LIN.

Auto on/off headlamps function sequence 

The auto on/off headlamps function is no more than a convenience system and does not exempt the driver from following the operating instructions in the road traffic regulations.

With the auto on/off headlamps, the low beams are automatically switched on or off. This occurs depending on the ambient brightness or depending on the activities of the wiper system:

Function sequence for activating auto on/off headlamps over the light sensor or rain/light sensor 

The light sensor or the rain/light sensor evaluates the ambient brightness. The front SAM control unit reads in the data of the light sensor or the rain/light sensor over the wiper/inside rearview mirror LIN and activates the low beams actuation if darkness is recognized.

Function sequence for activating auto on/off headlamps via wiper activities 

If the low beams are switched on or off due to the activities of the wiper system, one refers to wiper, rain or adverse weather light. The front SAM control unit controls the wiper system and evaluates the data of the rain/light sensor or the wipe request via the combination switch for this. If the windshield wiper system is activated for t = ≥ 20 s with a wipe cycle time of t < 6 s, the front SAM control unit activates low beam actuation. If there are no wipe cycles for t ≥ 60 s, low beams actuation is deactivated.

IMPORTANT Auto on/off headlamps switch-off conditions:

In the event of light sensor or rain/light sensor failure, the auto on/ off headlamps are not deactivated until the engine is switched off. When the vehicle is being driven through a tunnel and if the wiper start suppression function is active, the auto on/off headlamps function remains switched on.

If the wiper start suppression function is canceled, the auto on/off headlamps remain active for an additional t = 60 s.

Behavior of the exterior lights with active auto on/off headlamps:

Journey commencement:

End of journey:

IMPORTANT The standing lights are switched off as soon as the driver door is opened with the transmitter key (circuit 15C) inserted.

Additional headlamp range adjustment function requirements 

Headlamp range adjustment (HRA [LWR]) function sequence 

The headlamp range adjustment is installed as passive safety equipment in vehicles fitted with halogen headlamps to prevent them from dazzling oncoming traffic. Depending on the load condition of the vehicle, the incline angle of the driving lights can be corrected by actuating the headlamp range controller (S1s8).

The left headlamp range adjustment actuator motor (E1m1) and the right headlamp range adjustment actuator motor (E2m1) are actuated voltage-coded in accordance with the position of the headlamp range adjuster. These then adjust the headlamp units in the front lamp units.

REFER TO SYSTEM WIRING DIAGRAMS Electrical function schematic for driving light actuation   PE82.10-P-2059-97FAC
  Overview of exterior lights system components   GF82.10-P-9998CE 
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