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

Model 205 

up to model year 2019 

with code 631 (Static LED headlamps, left-hand traffic) 

Model 205 

up to model year 2019 

with code 632 (Headlamps, LED, static, right-side traffic) 

Model 205 

up to model year 2019 

with code 640 (High-performance LED) 

Model 205 

up to model year 2019 

with code 641 (Dynamic LED headlamps, left-hand traffic) 

Model 205 

up to model year 2019 

with code 642 (Dynamic LED headlamps, right-hand traffic) 

Model 253 (except 253.99) 

with code 631 (Static LED headlamps, left-hand traffic) 

Model 253 (except 253.99) 

with code 632 (Headlamps, LED, static, right-side traffic) 

Model 253 (except 253.99) 

with code 640 (High-performance LED) 

Model 253 (except 253.99) 

with code 641 (Dynamic LED headlamps, left-hand traffic) 

Model 253 (except 253.99) 

with code 642 (Dynamic LED headlamps, 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.

The driving lights actuation encompasses the following subfunctions:

IMPORTANT The driving lights are actuated corresponding to the position of the exterior lights switch (S1). The front SAM control unit (N10/6) reads in the status of the exterior lights switch directly.

Additional function requirements for low beams actuation 

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

IMPORTANT The standing lights are active during low beams actuation.

Function sequence for low beam actuation 

Turning the exterior lights switch into the "low beams" position requests actuation of the low beams.

The front SAM control unit directly reads in the status of the exterior lights switch and sends the "Low beams ON" request via interior CAN, electronic ignition lock control unit and periphery CAN (CAN PER) to the left headlamp control unit (E1n9) in the left front lamp unit (E1) and to the right headlamp control unit (E2n9) in the right front lamp unit (E2).

Vehicles with LED headlamps (static) (with CODE 631 (Static left-hand traffic LED headlamp), or code 632 (Static right-hand traffic LED headlamp)) 

The left headlamp control unit directly actuates the left low beam (E1e2). The right headlamp control unit directly actuates the right low beam (E2e2).

Vehicles with LED headlamps (dynamic) (with CODE 640 (High Performance LED), or code 641 (Dynamic left-hand traffic LED headlamp), or code 642 (Dynamic right-hand traffic LED headlamp)) 

The left headlamp control unit sends the "Low beams ON" request over the left headlamp LIN (LIN G1) to the left front actuation module, LED exterior lighting (E1n7).

The left front actuation module, LED exterior lighting actuates the left low beam (short range) (E1e15) and the left low beam (long range) (E1e16) directly.

The right headlamp control unit sends the "Low beams ON" request over the right headlamp LIN (LIN G2) to the right front actuation module, LED exterior lighting (E2n7).

The right front actuation module, LED exterior lighting actuates the right low beam (short range) (E2e15) and the right low beam (long range) (E2e16) directly.

The front SAM control unit also transmits the request "Low beams indicator lamp On" via the interior CAN, the electronic ignition lock control unit and the user interface CAN (CAN HMI) to the instrument cluster (A1), which then actuates the low beams indicator lamp (A1e67).

Additional function requirements, high beam actuation 

IMPORTANT The electronic ignition lock control unit sends the status of circuit 15 to the front SAM control unit via the interior CAN.

Function sequence for high beam actuation 

The high beams actuation is comprised of the following subfunctions:

Function sequence for high beams (manual) 

High beam actuation is requested by pushing the combination switch (S4) forward.

The steering column tube module control unit (N80) directly reads in the switch position of the combination switch and sends it to the front SAM control unit via the chassis FlexRay (Flex E), electronic ignition lock control unit and interior CAN.

The front SAM control unit sends the "High beams ON" request via interior CAN, electronic ignition lock control unit and peripherals CAN to the headlamp control units.

Vehicles with LED headlamps (static) 

The left headlamp control unit directly actuates the left high beam (E1e1). The right headlamp control unit directly actuates the right high beam (E2e1).

Vehicles with LED headlamps (dynamic) 

The left headlamp control unit sends the "High beams ON" request over the left headlamp LIN to the left front actuation module, LED exterior lighting.

The right headlamp control unit sends the "High beams ON" request over the right headlamp LIN to the right front actuation module, LED exterior lighting.

Model 205 

The left front actuation module, LED exterior lighting directly actuates the left high beam.

The right front actuation module, LED exterior lighting directly actuates the right high beam.

Model 253 

The left front actuation module, LED exterior lighting actuates the left low beam (long range) with greater power. The left headlamp control unit actuates the left light distribution actuator motor (E1m3) directly. The right front actuation module, LED exterior lighting actuates the right low beam (long range) with greater power. The right headlamp control unit actuates the right light distribution actuator motor (E2m3) directly. The light output is increased by these measures and the entire light beam of the low beams (long range) is released for illuminating the roadway.

The front SAM control unit also transmits the status "High beams ON" via the interior CAN, the electronic ignition lock control unit and the user interface CAN to the instrument cluster, which then actuates the high beams indicator lamp (A1e3).

Function sequence for headlamp flasher 

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.

IMPORTANT If the combination switch is pulled back and held, the high beam actuation is active for maximum t = 30 s. The permanently present request is then interpreted as a "stuck combination switch".

Additional function requirements for daytime running lights actuation 

IMPORTANT Model 205, Model 253 with CODE 494 (USA version), Model 205, Model 253 with CODE 498 (Japan version)

The instrument cluster sends the "Daytime running lights ON" menu status to the front SAM control unit via user interface CAN, electronic ignition lock control unit and interior CAN.

IMPORTANT The electronic ignition lock control unit sends the status of circuit 15 to the front SAM control unit via the interior CAN.

The "Engine running" or "Drivetrain operational" signal is sent by the CDI control unit (N3/9) (diesel engine) or the ME-SFI [ME] control unit (N3/10) (gasoline engine) to the front SAM control unit via drive train CAN (CAN C1), powertrain control unit (N127), chassis FlexRay, electronic ignition lock control unit and interior CAN.

The instrument cluster sends the vehicle speed to the front SAM control unit via user interface CAN, electronic ignition lock control unit and interior CAN.

The front SAM control unit reads in the status of the exterior lights switch directly.

Function sequence for daytime running lights actuation 

The front SAM control unit reads in all the relevant information, evaluates it and sends the "Daytime running lights ON" request for vehicles except CODE 498 (Japan version) via interior CAN, electronic ignition lock control unit and the periphery CAN to the headlamp control units.

Model 205 

The left headlamp control unit actuates the daytime running light in the left parking light, standing light and daytime running light (E1e13) directly. The right headlamp control unit actuates the daytime running light in the right parking light, standing light and daytime running light (E2e13) directly.

Model 253 

The left headlamp control unit actuates the daytime running light in the left position light, daytime running light and turn signal light (E1e25) (except Economic Commission for Europe (ECE) vehicles) or in the left position light, daytime running light, turn signal light and ambient light (E1e26) (ECE vehicles) directly. The right headlamp control unit actuates the daytime running light in the right position light, daytime running light and turn signal light (E2e25) (except ECE vehicles) or in the right position light, daytime running light, turn signal light and ambient light (E2e26) (ECE vehicles) directly.

IMPORTANT Model 205, Model 253 with CODE 498 (Japan version)

Instead of the daytime running lights, the low beam actuation (up to 31.05.2015) or the standing lights actuation (as of 01.06.2015) is activated.

Depending on the ambient light situation, taillight actuation (without license plate illumination) is activated in twilight a well as daytime running lights actuation. The low beams actuation is activated as it gets darker.

This function is not available in the following countries:

IMPORTANT Model 205, Model 253 with CODE 460 (Canada version)

When the vehicle is stationary, the daytime running lights actuation is switched off after t = 3 min. When the vehicle then starts to move again, the front SAM control unit automatically activates daytime running lights actuation.

Additional function requirements for auto on/off driving lights 

IMPORTANT The electronic ignition lock control unit sends the status of circuit 15 to the front SAM control unit via the interior CAN.

The "Engine running" or "Drive train ready" signal is sent by the CDI control unit or the ME-SFI [ME] control unit to the front SAM control unit via drive train CAN, powertrain control unit, chassis FlexRay, electronic ignition lock control unit and interior CAN.

The instrument cluster sends the vehicle speed to the front SAM control unit via user interface CAN, electronic ignition lock control unit and interior CAN.

The front SAM control unit reads in the status of the exterior lights switch directly.

Function sequence for auto on/off driving lights 

In the auto on/off driving lights, the low beams are automatically switched on or off.

The auto on/off driving lights are purely a comfort function and do not relieve the driver of the need to follow the operating instructions as prescribed by the road traffic regulations.

Behavior of exterior lights when auto on/off driving lights activated at night
Start of trip  Standing lamp  Low beam 
Circuit 15C OFF Off Off
Circuit 15C ON Off Off
Circuit 15R ON On Off
Terminal 15 ON On Off
"Engine running" or "drive train operational" signal set or vehicle speed v > 3 km/h On On (high beams permissible)
End of trip 
At the end of the trip, the auto on/off driving lights and ambient illumination functions may overlap.
Standing lamp  Low beam 
"Engine running" or "drive train operational" signal set or vehicle speed v > 3 km/h On On (high beams permissible)
Circuit 15R ON On Off
Circuit 15C ON (driver door closed) On Off
Circuit 15C ON (driver door open) Off Off
Circuit 15C OFF Off Off

The low beams are switched on or off depending on the ambient brightness or depending on the activities of the windshield wiper system:

Function sequence for auto on/off driving lights over light sensor in rain/light sensor with additional functions 

The ambient brightness is detected by the light sensor. The rain/light sensor with additional functions reads in the light sensor signals directly, evaluates them and sends the "Low beams ON" request via rain/light sensor-LIN (LIN B16) to the front SAM control unit, which then activates the low beams actuation.

IMPORTANT In the event of any light sensor failure, the auto on/off driving lights 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 driving lights function remains switched on.

Function sequence for auto on/off driving lights over wiper activities 

If the low beams are switched on or off due to the activities of the windshield wiper system, one refers to adverse weather light. The front SAM control unit actuates the windshield wiper system.

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

Additional function requirements for automatic headlamp range adjustment (HRA [LWR]) (with CODE 631 (Static left-hand traffic LED headlamp), or code 632 (Static right-hand traffic LED headlamp), and except CODE 460 (Canada version), and except CODE 494 (USA version), or code 640 (High Performance LED), or code 641 (Dynamic left-hand traffic LED headlamp), or code 642 (Dynamic right-hand traffic LED headlamp)) 

Function sequence for automatic headlamp range adjustment (HRA [LWR]) (with CODE 631 (Static left-hand traffic LED headlamp), or code 632 (Static right-hand traffic LED headlamp), and except CODE 460 (Canada version), and except CODE 494 (USA version), or code 640 (High Performance LED), or code 641 (Dynamic left-hand traffic LED headlamp), or code 642 (Dynamic right-hand traffic LED headlamp)) 

The automatic HRA [LWR] corrects the headlamp range of the vehicle headlamps in accordance with the load or the vehicle pitch motions induced by the vehicle dynamics.

Determining vehicle level:

Model 205 except CODE 483 (ADVANCED AGILITY package) and CODE 489 (AIRmatic), Model 253 except CODE 489 (AIR BODY CONTROL):

Model 205 with CODE 483 (ADVANCED AGILITY package) and CODE 489 (AIRmatic), Model 253 with CODE 489 (AIR BODY CONTROL):

The AIRmatic control unit (N51/3) (Model 205) or the AIR BODY CONTROL control unit (N51/3) (Model 253) sends information on the vehicle level over the chassis FlexRay, electronic ignition lock control unit and the periphery CAN to the left headlamp control unit. The AIRmatic control unit evaluates the signals from the following components for this:

IMPORTANT Model 205

up to model year 2019

with code 640 (High-performance LED)

Model 205

up to model year 2019

with code 641 (Dynamic LED headlamps, left-hand traffic)

Model 205

up to model year 2019

with code 642 (Dynamic LED headlamps, right-hand traffic)

Model 253 (except 253.99)

with code 640 (High-performance LED)

Model 253 (except 253.99)

with code 641 (Dynamic LED headlamps, left-hand traffic)

Model 253 (except 253.99)

with code 642 (Dynamic LED headlamps, right-hand traffic)

Zero-point programming is performed during production to compensate for suspension tolerances. With successful programming, visual feedback occurs through the movement of the headlamp units "center-down-up-center" and "center-outside-center". This reference sequence always occurs following a change of the circuit 30L status, i.e. after bus idle.

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 and the reaction time of the automatic headlamp range adjustment is significantly reduced.

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

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

The headlamp control units operate in a in master-slave combination, whereby the left headlamp control unit acts as the master and synchronizes the right headlamp control unit.

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

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

  Electrical function schematic for driving lights actuation   PE82.10-P-2059-97FBB
  Overview of exterior lights system components   GF82.10-P-9998RF