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

MODEL 463.306 /336 /346 as of model year 2011 /YoM 10 

MODEL 463.202 /222 /236 /237 as of model year 2009 /YoM 08 

MODEL 463.247 /248 /249 /254 up to 31.8.08 as of model year 2007 

MODEL 463.270 /271 /303 /340 /341 as of model year 2007 

Fig 1: Headlamp Control Function Diagram
G07705732Courtesy of MERCEDES-BENZ USA

General driving light actuation function sequence 

The driving lights actuation consists of several subfunctions:

Low beam actuation 

Function requirements 

Low beam actuation function sequence 

The position of the rotary light switch is read in by the front signal acquisition and actuation module.

The front SAM routes the request directly to the xenon headlamp control unit.

The xenon headlamp control unit then actuates the left xenon bulb (E1e8) and the right xenon bulb (E2e8).

IMPORTANT When low beam is switched on the light cone is partially hidden by covers.

High-beams actuation 

Function requirements 

High beam actuation function sequence 

The high beam actuation is requested by pressing the combination switch forward.

The steering column tube module records the switch position of the combination switch and sends the request to the front SAM via the interior CAN.

The front SAM receives the request and actuates the high beam solenoids, whereby the covers which are partially hiding the light cone of the xenon bulbs are moved away.

Headlamp flasher function sequence 

To activate the headlamp flasher, the combination switch must be pulled backwards. The high beam actuation remains active as long as the combination switch is pulled and held.

The function sequence and signal flow of the headlamp flasher actuation are similar to the high beam actuation function.

Feedback 

An active headlamp flasher actuation is forwarded by the front SAM to the instrument cluster via the interior CAN.

This then actuates the high beam indicator lamp.

Daytime running lamps actuation 

Function requirements 

Daytime running lights actuation function sequence 

The daytime running lights actuation is activated by the front SAM. The front SAM actuates the xenon bulbs via the xenon headlamp control units.

IMPORTANT In countries with statutory daytime running lamp regulations, only the headlamp flasher is permitted in daytime running lamp mode, but not the high beam.

Automatic headlamp actuation 

Function requirements 

Auto on/off headlamps function sequence 

Function at start of journey 

Function at end of journey 

Function while driving 

The automatic light switch daylight sensor records the ambient brightness. When darkness is detected, the corresponding request is forwarded by the overhead control panel control unit to the front SAM via the interior CAN.

The front SAM then actuates the xenon bulbs via the xenon headlamp control units.

Function during wiper operation 

When the wiper system is actuated for t = 20 s with a wipe cycle period of t < 6 s, the front SAM actuates the xenon bulbs via the xenon headlamp control units.

If there is no wipe cycle for t = 60 s, the driving lights are switched off.

Automatic headlamp range adjustment 

Function requirements 

Automatic headlight range adjustment function sequence 

The automatic headlamp range adjustment serves to correct the headlamp range of the vehicle headlamps as a function of the load or the vehicle pitch motions induced by the vehicle dynamics.

To this end, the headlamp range adjustment control unit reads in the headlamp range adjustment rear axle sensor and the front axle sensor (headlamp range adjustment).

The headlamp range adjustment control unit actuates the left headlamp range adjustment motor and the right headlamp range adjustment motor directly.

Cornering illumination 

Function requirements 

Cornering lights function sequence 

The cornering illumination function enables the traffic lane to be better illuminated in the cornering direction and it is implemented by the left front fog lamp or the right front fog lamp.

In the process, only one front fog lamp is actuated - the fog lamp on the inside of the curve when driving forwards and the fog lamp on the outside of the curve when reversing. It is always switched on and off with dimming.

The front SAM is responsible for evaluating all relevant information and the resulting actuation.

The cornering direction is recognized by the turn signaling function or via the steering angle.

The steering angle, detected by the steering angle sensor, is read in by the steering column tube module and transmitted to the EZS control unit via the drive train CAN. The steering angle is routed by the EZS control unit to the front SAM via the interior CAN.

Pressing the combination switch requests the turn signaling function.

The steering column tube module records the switch position of the combination switch and sends the request to the front SAM via the interior CAN.

The front SAM receives the request and actuates the corresponding front fog lamp.

From a speed of v < 40 km/h, the request via turn signaling has priority over the request by the steering angle.

  Headlamp range adjustment axle sensor, component description A51, A52 GF82.10-P-4153G 
  Light sensor component description B32/1 GF54.21-P-6001G
  Component description for front SAM control unit with fuse and relay module N10/1 GF54.21-P-6070G
  Steering angle sensor, component description N49 GF42.45-P-5107G
  Component description for overhead control panel control unit N70 GF82.20-P-5216G 
  Component description of headlamp range adjustment control unit N71 GF82.10-P-2112G 
  Electronic ignition/starter switch control unit (EZS), component description N73 GF80.57-P-6000G
  Component description for steering column tube module N80 GF54.21-P-6050G
  Rotary light switch, component description S1 GF82.10-P-4106G 
  Combination switch, component description S4 GF82.30-P-5000G