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

GF82.10-P-2009LEA Headlamp Control, Function
- with CODE (615) Bi-xenon headlamp unit with integrated curve illumination
- with CODE (616) Bi-xenon headlamp unit with integrated asymmetrical curve illumination

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 comprises 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 function requirement for low beam actuation
^ 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 upper control panel control unit (N72/1) reads in the status of the rotary light switch via the instrument panel LIN (LIN 1) and forwards it via the interior CAN to the front SAM control unit with fuse and relay module (N10/1).
The EIS control unit (N73) transmits the circuit status c. 15 to the front SAM control unit via the interior CAN and additionally provides it to the chassis CAN (CAN E).
The central gateway control unit (N93) relays the circuit status c. 15 via the front end CAN (CAN G) to the Xenon headlamp control unit (E1n1) to the left front lamp unit (E1) which synchronizes the xenon headlamp control unit (E2n1) to the right front lamp unit E2).

The front SAM control unit evaluates all relevant information and outputs the request "Switch on low beams" via a voltage signal directly to the xenon headlamp control units.
The xenon headlamp control unit at the left front lamp unit actuates the left bi-xenon lamp with integrated ignition module (E1e10), and the xenon headlamp control unit at the right front lamp unit actuates the right bi-xenon lamp with integrated ignition module (E2e10).

Additional function requirements, high beam actuation
^ For high beams function: low beams On
^ For headlamp flasher function: C. 15R ON (provided by EIS control unit)

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 directly by the steering column tube module (N80), sent to the chassis CAN and forwarded by the central gateway control unit via the interior CAN to the front SAM control unit and sent via the front end CAN to the xenon headlamp control unit on the left front headlight unit. The xenon headlamp control unit at the left front lamp unit synchronizes the xenon headlamp control unit at the right front lamp unit via the front end CAN.
Parallel to this, the front SAM control unit transmits the status "High beam actuation activated". The central gateway control unit routes it via the central CAN (CAN F) to the instrument cluster (A1), which then actuates the high beam indicator lamp (A1e3).

The xenon headlamp control units operate in a master-slave combination, whereby the xenon headlamp control unit at the left front lamp unit has the role of the master control unit.

Model 216, model 221 up to 31.5.09, model 221 as of 1.6.09 without code (615) Bi-xenon headlamp unit with integrated curve illumination and without code (616) Xenon headlamp unit with asymmetrical integrated curve illumination and without code (621) Intelligent Light System (left-hand traffic) and without code (622) Intelligent Light System (right-hand traffic):
The xenon headlamp control unit on the left lamp unit actuates the left high beam solenoid (E1I1) and the xenon headlamp control unit on the right headlight unit actuates the right high beam solenoid (E2I1).

The supply voltage for actuation of the high beam solenoid is provided by the front SAM control unit.

On model 221 as of 1.6.09 with code (615) Bi-xenon headlamp unit with integrated curve illumination or code (616) Xenon headlamp unit with asymmetrical integrated curve illumination or code (621) Intelligent Light System (left-hand traffic) or code (622) Intelligent Light System (right-hand traffic), the left light distribution actuator motor (E1m3) and right light distribution actuator motor (E2m3) are installed instead of the high beam solenoids.
The light distribution actuator motors are actuated by the corresponding xenon headlamp control unit via the headlamp internal local interconnect network (LIN).
The panels which partially cover up the bi-xenon light cone, are folded away thereby releasing the entire light beam to illuminate the traffic lane.

On vehicles without code (610) Night view assist, the front SAM control unit on model 216 additionally actuates the left high beam/ motorway spotlight (E1e1) and the right high beam/motorway spotlight (E2e1) and on model 221 the left high beam (E1e1) and the right high beam (E2e1).

For vehicles with code (610) Night View Assist, the high beams are replaced by the left infrared lamp (E1e11) and the right infrared lamp (E2e11).

Headlamp flasher function sequence
The function sequence and signal path for the headlamp flasher function correspond to that of the high beam function. 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.

On vehicles with code (610) Night View Assist, the low beam actuation has to be activated, because infrared lamp high beams are installed instead.

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)
- Standing light (with code (460) Canada version)

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 central CAN.
The status of circuit 61 is provided by the CDI control unit (N3/9) (on diesel engine) or by the motor electronics control unit (N3/10) (on gasoline engine) on the chassis CAN.
Information about the vehicle speed is made available by the instrument cluster on the central CAN.

The central gateway control unit routes all relevant information via the interior CAN to the front SAM control unit.

Model 216, model 221 up to 31.5.09,
Model 221 as of 1.6.09 with code (498) Japan version:
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 headlamp control units, which then actuates the bi-xenon lamps.

For vehicles with code (460) Canada version, only the bi-xenon lights are actuated when the rotary light switch is set to "AUTO" and the rain/light sensor (B38/2) flags the "Day" signal.

Model 221 as of 1.6.09 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).

When the rotary light switch is in the "AUTO" position and the rain/ light sensor signals the status "Darkness recognized" or the wiper system is activated, the low beams are actuated and the daytime running light headlamp is actuated with reduced power.

On vehicles with code (460) Canada version, the low beam actuation is always activated additionally. However, to increase the service life of the bi-xenon lamps, they are actuated during Daytime" with reduced power. The daytime running lamps are also 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. When the vehicle is at a standstill the daytime running lights function is deactivated following the expiration of a time interval of t = 3 minutes.

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).

If the daytime running lights are defective, the daytime running light function is output by the parking lamp and low beam actuation.

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.

Circuit status c. 61 is provided by the CDI control unit or ME-SFI control unit to the chassis CAN.
Information about the vehicle speed is made available by the instrument cluster on the central CAN.
The central gateway control unit routes all relevant information via the interior CAN to the front SAM control unit.
The ambient brightness is recorded by the rain/light sensor.
The overhead control panel control unit (N70) reads in the rain/ light sensor data and forwards them over the interior CAN to the front SAM control unit. If darkness is recognized the front SAM control unit actuates the low beams.
If the 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 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 = 60 s.

Additional function requirements for headlamp range adjustment
^ Engine running (circuit 61 ON) n > 300 rpm
^ Driving lights On (low beam/high beam)

Headlamp range adjustment (HRA [LWR]) function sequence
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.
For model 221 without code (487) Active Body Control (ABC), the data of the left front level sensor (B22/8), right front level sensor (B22/9) and the rear axle level sensor (B22/3) are read in by the AIRmatic with ADS control unit (N51), evaluated and made available on the chassis CAN.

For vehicles with code (487) Active Body Control (ABC), the data of the left front level sensor, right front level sensor, left rear level sensor (B22/7) and the right rear level sensor (B22/10) are read in by the ABC control unit (N51/2), evaluated and made available on the chassis CAN.

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.

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

The regenerative braking system (N47-5) (except model 221.095/195) or regenerative braking system control unit (N30/6) (model 221.095/195) provides information on the wheel speed and wheel rotation direction as vehicle speed indicator to the chassis CAN.
All relevant information is made available by the central gateway control unit to the xenon headlamp control unit at the left front lamp unit via the front end CAN.

The xenon headlamp control unit on the left front lamp unit receives the data, evaluates it and transmits the corresponding correction data to the xenon headlamp control unit on the right front lamp unit.
The xenon headlamp control unit on the left headlight unit actuates the left headlamp range adjustment motor (E1m1) and the xenon headlamp control unit on the right headlight unit actuates the right headlamp range adjustment motor (E2m1) accordingly.