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

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

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

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

IMPORTANT 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).

Low beam actuation function sequence 

Turning the exterior lights switch to the "manual driving lights" position requests actuation of the low beams. The front SAM control unit reads in the status of the exterior lights switch and forwards the "low beams On" request over the voltage signal (circuit 56) directly to the following components:

In addition, the front SAM control unit sends the request "Low beams indicator lamp On" via interior CAN to the instrument cluster (A1), which then actuates the low beams indicator lamp (A1e67).

IMPORTANT Model 204.0/2 up to 28.2.11, model 204.9

The xenon light control units operate in a master/slave combination, whereby the left xenon light control unit acts as the master and synchronizes the right xenon light control unit. Both xenon light control units communicate with each other via the front end CAN (CAN G).

With model 204.0/2 up to 28.2.11 the left xenon light control unit actuates the left xenon bulb with integral ignition module (E1e10) and the right xenon light control unit actuates the right xenon bulb with integral ignition module (E2e10).

With model 204.0/2 as of 1.3.11, model 204.3 the xenon light power supply module actuates the xenon bulbs.

The left xenon light power supply module communicates over the left headlamp LIN (LIN G1) with the headlamp control unit (N71/1). The right xenon light power supply module communicates over the right headlamp LIN (LIN G2) with the headlamp control unit. The headlamp control unit regulates the light output of the xenon bulbs.

With model 204.9 the xenon light power supply modules, after being appropriately enabled by the respective xenon light control unit, actuate the xenon bulbs.

The left xenon light power supply module communicates over the left headlamp LIN with the left xenon light control unit.

The right xenon light power supply module communicates over the right headlamp LIN with the right xenon light control unit.

The xenon light control units regulate the light output of the xenon bulbs.

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) reads in the switch position of the combination switch and transmits it to the front

SAM control unit via chassis CAN (CAN E).

The front SAM control unit receives the switch position of the combination switch, uses it to generate the "high beams ON" request and then on model 204.0/2 up to 28.2.11, model 204.9, it actuates the following components:

The front SAM control unit also sends the "high beams ON" request over the interior CAN to the instrument cluster, which then actuates the high beams indicator lamp (A1e3).

With model 204.0/2 as of 1.3.11, model 204.3 the front SAM control unit sends the "high beams ON" request over the front end CAN to the headlamp control unit.

The headlamp control unit then actuates the left light distribution actuator motors (E1m3) over the left headlamp LIN and the right light distribution actuator motor (E2m3) over the right headlamp LIN.

Model 204.0/2 up to 28.2.11, model 204.9:

When the high beam solenoids are actuated, the covers that partially block the light cones of the xenon bulbs are moved away, and the entire light beam is released for illuminating the road surface.

Model 204.0/2 as of 1.3.11, model 204.3:

When the light distribution actuator motors are actuated the covers that partially block the light cones of the xenon bulbs are moved away, and the entire light beam is released for illuminating the road surface.

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".

Because with model 204.9, model 204.0/2 as of 1.3.11 and model 204.3 no additional high beams are installed, the low beams actuation is activated and the high beam solenoid or the light distribution actuator motors are actuated.

In vehicles with code (460) Canada version or code (494) USA version, the high beams function must not be used if left front fog lamp (E5/1) and right front fog lamp (E5/2) actuation is active. The current incoming request has priority.

IMPORTANT Front fog lamps are installed only on vehicles up to 30.11.09 and as of 1.12.09 without code (621) Intelligent light system (left-hand traffic) and without code (622) Intelligent light system (right - hand traffic) or with code (498) Japan version).

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.

Vehicles up to 30.11.09 or as of 1.12.09 (model 204.0/2 up to 28.2.11) without code (621) Intelligent Light System (left-hand traffic) and without code (622) Intelligent Light System (right-hand traffic):

The front SAM control unit reads in all of the relevant information and outputs the request "Switch on low beams" via a voltage signal directly to the xenon light control units.

In model 204.0/2, the xenon light control units then actuate the xenon bulbs.

In model 204.9 the front SAM control unit also actuates the xenon light power supply modules.

In accordance with the release by the relevant xenon light control unit, the xenon light power supply modules actuate the xenon bulbs.

In vehicles with code (460) Canada version or code (494) USA version, low beam actuation is activated in accordance with the status of the light sensor (B38/1) (without code (345) Rain sensor) or the rain/light sensor (B38/2) (with code (345) Rain sensor).

When darkness is recognized, the front SAM control unit activates both low beam actuation and standing lights actuation.

During the day the xenon bulbs are actuated at reduced power. The parking lights are not actuated.

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).

Vehicles as of 1.12.09 without code (498) Japan version and with code (621) Intelligent Light System (left-hand traffic) or code (622) Intelligent Light System (right-hand traffic), model 204.0/2 as of 1.3.11 and model 204.3:

The front SAM control unit reads in all of the relevant information, evaluates this and actuates the left daytime running lights headlamp (E1/3) and the right daytime running lights headlamp (E2/3).

IMPORTANT On vehicles with code (498) Japan version, the daytime running light function is output by the low beam actuation, because daytime running lights are not installed.

During darkness, the front SAM control unit actuates the daytime running light with reduced power and activates the low beam actuation.

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.

On vehicles with code (460) Canada version, the low beam actuation is always activated additionally.

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

On vehicles with code (460) Canada version, the daytime running light actuation is switched off after expiration 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 daytime running 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.

The high beams are permissible only when the high beams 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 instrument cluster sends the vehicle speed via interior CAN. The front SAM control unit reads in the status of the exterior lights switch. 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 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 automatic headlamp range adjustment function requirements 

Function sequence for automatic HRA [LWR] 

The automatic HRA [LWR] permits the correction of the headlamp range of the vehicle headlamps as a function of the load or the vehicle pitch motions induced by the vehicle dynamics.

The CDI control unit or the ME-SFI [ME] control unit sends the engine RPM and the circuit 61 status or the "PT_Rdy" signal over the chassis CAN, front SAM control unit and the front end CAN to the left xenon light control unit or to the headlamp control unit.

To determine the vehicle level at any given time, the left xenon light control unit (model 204.0/2 up to 28.2.11, model 204.9) or the headlamp control unit (model 204.0/2 as of 1.3.11, model 204.3) with vehicles without code (483) ADVANCED AGILITY package, the signals of the left rear level sensor (B22/7) and the left front level sensor (B22/8) are read in directly.

With vehicles with code (483) ADVANCED AGILITY package, the adaptive damping system control unit (N51/5) sends all the data required to evaluate the vehicle level over the chassis CAN, front SAM control unit and the front end CAN to the left xenon light control unit or the headlamp control unit.

IMPORTANT Zero point programming is performed at the end of the line to compensate vehicle tolerances.

With successful programming, visual feedback occurs through the movement of the headlamp units "center-down-up-center".

If the vehicle is moving at a constant speed, the automatic headlamp range adjustment system operates in "static mode" at a slow adjustment rate.

When the vehicle is accelerated, the "dynamic mode" is activated by highly reducing the reaction time of the system.

The "dynamic mode" is activated depending on the speed change and additional signals from the brake pedal and the accelerator pedal positions.

IMPORTANT When the vehicle is standing automatic headlamp range adjustment is accomplished in the "dynamic mode".

Information on wheel speeds and wheel rotation directions, as an indicator of vehicle speed is sent by the Electronic Stability Program control unit (N30/4) over the chassis CAN, front SAM control unit and the front end CAN to the left xenon light control unit or to the headlamp control unit.

IMPORTANT The xenon light control units operate in a master/slave combination, whereby the left xenon light control unit acts as the master and synchronizes the right xenon light control unit.

The left xenon light control unit actuates the left headlamp range adjustment actuator motor (E1m1) directly.

The right xenon light control unit actuates the right headlamp range adjustment actuator motor (E2m1) directly.

The headlamp control unit actuates the left headlamp range adjustment actuator motor over the left headlamp LIN and the right headlamp range adjustment actuator motor over the right headlamp LIN.

REFER TO SYSTEM WIRING DIAGRAMS Electrical function schematic for driving light actuation Model 204.0/2 up to 28.2.11 PE82.10-P-2059-97FAD
Model 204.0/2 as of 1.3.11, model 204.3 PE82.10-P-2059-97FAF
Model 204.9 PE82.10-P-2059-97FAE
  Overview of exterior lights system components   GF82.10-P-9998CE 
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