Front Fog Light Actuation, Function - GF82.10-P-3070RD

Model 172.4 up to model year 2017 

Function requirements, general 

• No overvoltage or undervoltage
• Standing lights On (exterior lights switch (S1) in "Standing lights" or "Manual driving lights" position; on vehicles with CODE 494 (USA version), only in "Manual driving lights" position)
• Exterior lights switch in "A" position
• Circuit 15 ON (when coded)

The electronic ignition lock control unit (N73) transmits the circuit 15 status to the front SAM control unit with fuse and relay module (N10/1) over the interior CAN (CAN B).

Front fog light actuation, 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.

The standing lights actuation, described in a separate document, is active during the front fog light actuation.

The fog light actuation function consists of the following partial functions:

• Function sequence for front fog lamp actuation (except CODE 615 (Bi-xenon headlamp with active curve lights) and except CODE 621 (Intelligent Light System (left-hand traffic)) and except CODE 622 (Intelligent Light System) and except CODE 240 (LED daytime running lights), up to 31.05.2015) 
• Rear fog light actuation function sequence 

Function sequence for front fog lamp actuation (except CODE 615 (Bi-xenon headlamp with active curve lights) and except CODE 621 (Intelligent Light System (left-hand traffic)) and except CODE 622 (Intelligent Light System) and except CODE 240 (LED daytime running lights), up to 31.05.2015) 

After pressing the front fog lamp switch (S1s11) on the exterior lights switch, the front fog lamp actuation is requested. The front SAM control unit directly reads in the status of the front fog lamp button. The front SAM control unit then actuates the left front fog lamp (E5/1) and the right front fog lamp (E5/2).

The active front fog light actuation is indicated visually to the driver.

To do so, the front SAM control unit sends the "Front fog lamp indicator lamp On" request via interior CAN to the instrument cluster (A1), which then actuates the front fog lamp indicator lamp (A1e57).

Model 172.4

up to model year 2017

with code 460 (Canada version)

Model 172.4

up to model year 2017

with code 494 (US version)

The front fog lamps and the high beams function must not be actuated at the same time. The last incoming request has priority.

Additional function requirements for rear fog light actuation 

• Low beam ON

Rear fog light actuation function sequence 

The rear fog light actuation is requested by pressing the rear fog light button (S1s10) on the exterior lights switch. The front SAM control unit directly reads in the status of the rear fog light button.

The front SAM control unit then sends the "switch on rear fog light" request via the interior CAN to the rear SAM control unit with fuse and relay module (N10/2).

The rear SAM control unit actuates the left rear fog light (E3e5) in the left rear lamp unit (E3) or the right rear fog light (E4e5) in the right rear lamp unit (E4) in accordance with the national code.

The active rear fog light actuation is indicated visually to the driver. To do so, the front SAM control unit sends the "Rear fog light indicator lamp On" request via interior CAN to the instrument cluster, which then actuates the rear fog light indicator lamp (A1e18).

If the vehicle is braked during active rear fog lamp actuation, the inner left brake light and taillight (E3e10) or the inner right brake light and taillight (E4e10) (depending on the country coding) are actuated with reduced output.

	Electrical function schematic for front fog light actuation		PE82.10-P-2056-97TAA
	Overview of exterior lights system components		GF82.10-P-9998RD