Front fog light actuation, function - GF82.10-P-3070GM

MODEL 164.1 as of model year 2009/YoM 08 model refinement package

MODEL 164.8, 251.0/1 as of model year 2009/YoM 08

Function requirements, front fog light actuation, general

No overvoltage or undervoltage (operating voltage range U ≥ 7 ≤ 17.5 V)
Standing lights on (rotary light switch (S1) in "Standing lights" or "Manual driving lights" position) in vehicles with code (460) Canada version or code (494) USA version only in "Manual driving lights" position
Circuit 15 ON (when coded)

The status of circuit 15 is sent by the EZS control unit (N73) to the interior CAN (CAN B).

Front fog light actuation in general

Front fog light actuation provides better illumination of the road while driving as well as illuminating the rear of the vehicle under bad weather conditions.

During front fog light actuation standing/parking lights actuation is also active, which is described in a separate Service Information.

Front fog light actuation consists of the following subfunctions:

Function sequence for front fog lamp actuation (model 164.1 up to 31.7.10 and as of 1.8.10 without code (236) Daytime running lights in LED design, model 164.8 up to 30.6.09 and as of 1.7.09 without code (236) Daytime running lights in LED design, model 251 up to 31.7.10 and as of 1.8.10 without code (614) Bi-xenon headlamp unit and without code (618) Bi-xenon headlamp)
Rear fog light actuation function sequence

Function sequence for front fog lamp actuation (model 164.1 up to 31.7.10 and as of 1.8.10 without code (236) Daytime running lights in LED design, model 164.8 up to 30.6.09 and as of 1.7.09 without code (236) Daytime running lights in LED design, model 251 up to 31.7.10 and as of 1.8.10 without code (614) Bi-xenon headlamp unit and without code (618) Bi-xenon headlamp)

Pulling out the rotary light switch up to the first notch requests actuation of the front fog lamps.

The status of the rotary light switch is read in by the upper control panel control unit (N72/1) via the instrument panel LIN (LIN 1) and made available on the interior CAN.

The front SAM control unit (N10) reads this in, actuates the left front fog lamp (E5/1) and the right front fog lamp (E5/2) and transmit "Front fog lamp actuation active" status via the interior CAN to the upper control panel control unit.

The upper control panel control unit then actuates the front fog lamp indicator lamp (S1e1) in the rotary light switch, therefore signaling that front fog lamp actuation is active.

When the automatic lamp substitution function is requested, the front fog lamps are actuated corresponding to the requested automatic lamp substitution function.

For vehicles with code (460) Canada version or code (494) USA version, the front fog lamp actuation and the high beams actuation must not be activated at the same time. The current incoming request has priority.

Rear fog light actuation function requirements

Rotary light switch set to manual driving lights

Rear fog light actuation function sequence

Rear fog light actuation is requested by pulling out the rotary light switch until the first detent (vehicles without front fog lamps) or the second detent (vehicles with front fog lamps).

The status of the rotary light switch is read in by the upper control panel control unit via the instrument panel LIN and made available on the interior CAN.

The front SAM control unit reads this in and transmits the "Switch on rear fog light" request via the interior CAN to the rear SAM control unit (N10/8).

The rear SAM control unit actuates the following components in accordance with the country coding:

Model 164:
- Left taillight and rear fog light (E3e2) or
- Right taillight and rear fog light (E4e2)
- Left or right rear fog lamp on trailer (with code (550) Trailer hitch)
Model 251:
- Left rear fog light (E3e5) or
- Right rear fog light (E4e5)
- Left or right rear fog lamp on trailer (with code (550) Trailer hitch or code (553) Mechanically folding trailer hitch)

In Economic Commission for Europe (ECE) vehicles the right taillight, side marker lamp and parking light (E3e8) or the right taillight, side marker lamp and parking light (E4e8) are actuated with output of P = 21 W and used as the rear fog light.

The rear fog light on the vehicle is not actuated during trailer operation.

In vehicles with code (460) Canada version or code (494) USA version, the trailer is not equipped with a rear fog light.

The front SAM control unit transmits the "Rear fog light actuation active" status via the interior CAN to the upper control panel control unit, which then actuates the rear fog light indicator lamp (S1e2) in the rotary light switch via the instrument panel LIN. Active rear fog light actuation is signaled by illumination of the front fog lamp indicator lamp.

If the transmitter key (A8/1) is removed from the EZS control unit when the rear fog light actuation is active, and then the driver door is opened, the instrument cluster (A1) actuates the warning buzzer (A1h1) and issues an appropriate message on the multifunction display (A1p13).

The request to deactivate rear fog light actuation via the rotary light switch prevents the rear fog light actuation from being activated automatically the next time the vehicle is driven with the low beams switched on.

Electrical function schematic for front fog light actuation	Model 164	PE82.10-P-2056-97MAA
Electrical function schematic for front fog light actuation	Model 251	PE82.10-P-2056-97RAA
Component description for front SAM control unit	N10	GF54.21-P-7010GM
Component description for rear SAM control unit	N10/8	GF54.21-P-7030GM
Upper control panel control unit, component description	N72/1	GF54.21-P-6040GM
EZS control unit, component description	N73 Model 251, model 164 (except 164.195)	GF80.57-P-6003GM
EZS control unit, component description	Model 164.195 * for USA only	GF80.57-P-6003GQH