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GF82.10-P-2114SXA Xenon Headlamp Control Unit, Component Description



GF82.10-P-2114SXA Xenon Headlamp Control Unit, Component Description
- with CODE (615) Bi-xenon headlamp unit with integrated curve illumination


Illustrated on model 221


Component Identification:






Location
One xenon headlamp control unit each is located on the underside of the left front lamp unit and on the underside of the right front lamp unit.

Tasks
^ Output control of the left bi-xenon lamp with integral ignition module (E1e10) and of the right bi-xenon lamp with integral ignition module (E2e10)
^ Switchover from low beam to high beam Actuation of automatic headlamp range adjustment (HRA [LWR])
^ Actuation of cornering illumination
^ Actuation of dynamic curve illumination
^ Actuation of motorway lights
(for code (622) Intelligent Light System (right-hand traffic))
^ Control of extended fog lights function
(for code (622) Intelligent Light System (right-hand traffic))

Function
The xenon headlamp control units operate in a master-slave combination and communicate with each other over the front end CAN.

The xenon headlamp control unit at the left front lamp unit is the master control unit.
It processes and evaluates incoming information and forwards it correspondingly to the xenon headlamp control unit on the right front lamp unit.

Bi-xenon light output control
When switching on the low-beam function, the ignition modules of the bi-xenon lamps are activated by the corresponding xenon headlamp control unit. These then ignite the bi-xenon lamps by means of a high-voltage pulse. If an electric arc of sufficient stability is detected, the xenon headlamp control units switch over to the output-limiting operation.
When the motorway lights function is active, the light output is increased to 37 W over the Xenon headlamp control units.

Switching between low beam/high beam
When the low-beam function is active, the lower half of the light beam is covered by a shield. When the high-beam function is requested, the respective shield is folded downwards. Actuation of the shields takes place electromechanically by the xenon headlamp control units via the left high beam solenoid (E1l1) in the left front lamp unit and via the right high beam solenoid (E2l1) in the right front lamp unit. The entire light beam is then available to illuminate the traffic lane.

Actuation of automatic headlamp range adjustment (HRA [LWR])
To correct the headlamp range of the vehicle headlamps on model 221 without code (487) Active Body Control (ABC), the vehicle level data are made available by the AIRmatic with ADS control unit (N51). On model 221 with code (487) Active Body Control (ABC) or model 216, this is done by the ABC control unit (N51/2).

The xenon headlamp control unit on the left front lamp unit evaluates the data, calculates correction data and transmits these data to the xenon headlamp control unit on the right front lamp unit.
The xenon headlamp control unit on the left front lamp unit correspondingly actuates the left headlamp range adjustment motor (E1m1), and the xenon headlamp control unit on the right front lamp unit actuates the right headlamp range adjustment motor (E2m1).

Actuation of cornering illumination
The xenon headlamp control unit on the left front lamp unit actuates the cornering illumination (E1e9), and the xenon headlamp control unit on the right front lamp unit actuates the cornering illumination (E2e9). The corresponding request is sent by the left and right turn signal switch (S4s1) or by the steering angle sensor (N49).

Control of dynamic curve illumination
The xenon headlamp control unit on the left front lamp unit actuates the left dynamic curve illumination motor (E1m2), the xenon headlamp control unit on the right front lamp unit actuates the right dynamic curve illumination motor (E2m2). The extent to which the headlamp units are swiveled in the process depends on various vehicle dynamics parameters.

Control of motorway lights
The motorway lights are realized by increasing the light output of the bi-xenon lights and by raising the left headlamp unit. On vehicles without code (610) Night View Assist, the left high beam/ motorway spotlight (E1e1) and the right high beam/motorway spotlight (E2e1) are additionally switched on.

Control of extended fog light function
To realize the extended fog light function, the headlamp unit of the left front lamp unit is swiveled outwards by 8° and lowered. To this end, the xenon headlamp control unit on the left front lamp unit actuates the left dynamic curve illumination motor and the left headlamp range adjustment motor accordingly.

After replacement, the xenon headlamp control units must be coded to match the vehicle model and national version.

Signal inputs and outputs
Discrete inputs:
^ Circuit 15 voltage supply
^ Circuit 56a high beam
^ Circuit 56b low beam
^ Circuit 31 ground

Discrete outputs:
^ Circuit 56b low beam
^ Headlamp range adjustment motor
^ Dynamic curve illumination motor

CAN signals:
The xenon headlamp control units are participants of the front end CAN.