GF82.10-P-2009GMA Headlamp Control, Function
GF82.10-P-2009GMA Headlamp Control, Function
- except CODE (615) Bi-xenon headlamp unit with integrated curve illumination
- except CODE (616) Bi-xenon headlamp unit with integrated asymmetrical curve illumination
- except CODE (621) Intelligent Light System (left-hand traffic)
- except CODE (622) Intelligent Light System (right-hand traffic)
Function requirements, driving lights actuation, general
^ No overvoltage or undervoltage (operating voltage range U ≥7 ≤17.5 V)
driving lights actuation, general
driving lights actuation includes all functions which serve the optimum illumination of the road while driving.
During driving light actuation, the standing/parking lights actuation is active, this is described in a separate document.
The driving lights actuation function is comprised of the following subfunctions:
^ Low beam actuation function sequence
^ High beam actuation function sequence
^ Daytime running lights actuation function sequence
^ Auto on/off headlamps function sequence
^ Headlamp range adjustment function sequence (HRA [LWR])
Additional low beams actuation function requirements
^ Circuit 15 On
Low beam actuation function sequence
Turning the rotary light switch (S1) to the "manual driving lights" switch request actuation of the low beams.
The status of circuit 15 is provided by the EIS [EZS] control unit (N73) on the interior CAN (CAN B).
The upper control panel control unit (N72/1) reads in the status of the rotary light switch via the instrument panel LIN (LIN 1) and transmits it via the interior CAN to the front SAM control unit (N10). As a result of this the front SAM control unit actuates the left low beam (E1e2) and right low beam (E2e2).
Additional function requirements, high beam actuation
^ For high beams function: circuit 15 and low beams On
^ For headlamp flasher function: circuit 15R On
High beam actuation function sequence
The high beams actuation is comprised of the following subfunctions:
^ Function sequence for high beams
^ Headlamp flasher function sequence
Function sequence for high beams
The high beams actuation is requested by pressing the combination switch (S4) forward.
The switch position of the combination switch is read in by the steering column tube module (N80) and made available on the engine compartment CAN (CAN-C). The central gateway control unit (N93) forwards this via the interior CAN to the front SAM control unit. The front SAM control unit then actuates the left high beam (E1e1) as well as the right high beam (E2e1) and transmits the status "High beam actuation active" via the interior CAN to the instrument cluster (A1). This then 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. The high beams actuation remains active for as long as the combination switch is held in this position.
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
^ Engine running (circuit 61 On) n > 300 rpm or vehicle speed v > 3 km/h
^ Function activated via the instrument cluster (only countries without legal daytime running lights specification)
^ Rotary light switch in position:
- Exterior lights OFF "0"
- Auto on/off headlamps "AUTO"
- "Left parking light" or "Right parking light" (can be coded)
Daytime running lights actuation function sequence
The request for the daytime running lights function is output depending on the country coding or activated manually by the instrument cluster on the interior CAN.
The circuit status of circuit 61 is provided on the engine compartment CAN by the CDI control unit (N3/9) (with diesel engine) or by the ME-SFI [ME] control unit (N3/10) (with gasoline engine) and forwarded by the central gateway control unit via the interior CAN to the front SAM control unit.
Information about the vehicle speed is made available by the instrument cluster on the interior CAN.
Model 164.1, model 251.0/1, model 164.8 up to 30.6.09:
The front SAM control unit reads in all of the relevant information and actuates the left low beam and the right low beam.
In vehicles with code (460) Canada version or code (494) USA version, the low beams are actuated in accordance with the ambient brightness. This is detected by the rain/light sensor (B38/2). The information from the rain/light sensor is read in by the overhead control panel control unit (N70) and transmitted via the interior CAN to the front SAM control unit. If it is dark, the front SAM control unit actuates both the low beams and the standing lights. During the day the low beams are actuated at reduced power (U = 13.2 V). The standing lights are not actuated.
Model 164.8 as of 1.7.09 without code (498) Japan version:
The front SAM control unit reads in all of the relevant information and actuates the left daytime running lights headlamp (E1/3) or the right daytime running lights headlamp (E2/3). If it is dark and the rotary light switch is in the "AUTO" position, in vehicles without code (460) Canada version and without code (494) USA version the front SAM control unit switches the daytime running lights headlamps off and activates the low beams.
In vehicles with code (460) Canada version or with code (494) USA version, the low beams are always activated as well.
The low beams and the daytime running lights headlamps are actuated at reduced power in daylight. When it is dark, only the daytime running lights headlamps are actuated with reduced power.
Daytime running lights actuation is deactivated as soon as the rotary light switch is moved to the "Standing lights" position or the "Manual driving lights" position.
In vehicles with code (460) Canada version or code (494) USA version, daytime running lights actuation is switched off when the vehicle is stationary after a time interval of t = 3 min. When the vehicle then starts to move again, the front SAM control unit automatically activates daytime running lights actuation.
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 only permissible if the driving lights have been switched on manually via the rotary light switch (without code (460) Canada version or without code (494) USA version).
Additional function requirements, auto on/off headlamps
^ Engine running (circuit 61 On) n > 300 rpm or vehicle speed v > 3 km/h
^ Rotary light switch in position "AUTO" or "0" (can be coded)
^ Rain/light sensor signals "Darkness detected"
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 auto on/off headlamps, low beam actuation is switched on or off depending on the ambient brightness. The auto on/off headlamps function can be switched on or off via the rain/light sensor or the activities of the wiper system.
Journey commencement:
- Transmitter key (A8/1) removed Standing lights/low beams OFF
- Circuit 15C ON Standing lights/low beams OFF
- Circuit 15R ON Standing lights ON
- Circuit 15 ON Standing lights ON
- Terminal 61 ON standing lights/low beams ON (high beams permissible)
End of journey:
- Terminal 61 ON standing lights/low beams ON (high beams permissible)
- Circuit 15R ON Standing lights ON
- Circuit 15C ON Standing lights ON
- Transmitter key disconnected Standing lights/low beams OFF
The standing lights are switched off, as soon as the driver door is opened with the transmitter key (circuit 15C) inserted.
The circuit status of circuit 61 is provided on the engine compartment CAN by the CDI control unit or by the ME-SFI [ME] control unit and forwarded by the central gateway control unit via the interior CAN to the front SAM control unit.
The ambient brightness is recorded by the rain/light sensor. The information from the rain/light sensor is read in by the overhead control panel control unit and transmitted via the interior CAN to the front SAM control unit. If darkness is recognized the front SAM control unit actuates the low beams.
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 ≥20 s, low beam actuation is deactivated.
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 active. If the wiper start suppression function is canceled, the auto on/off headlamps function remains active for an additional t = 20 s.
Additional headlamp range adjustment function requirements
^ Low beams On
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 adjustment selector wheel (S1s8). The left headlamp range adjustment motor (E1m1) and the right headlamp range adjustment motor (E2m1) are actuated voltage-coded in accordance with the position of the headlamp range adjustment selector wheel. These then adjust the headlamp units in the front lamp units.
