Wiper system automatic speed reduction, function - GF82.30-P-4006GM

MODEL 164.1 as of model year 09/YoM 08 model refinement package except CODE (494) USA version 

MODEL 164.8, 251.0 /1 as of model year 09/YoM 08 except CODE (494) USA version 

Function requirements, general 

- C. 15R On

- Combination switch (S4) in position "3" or "4"

- Speed reduced to v < 8 km/h

Automatic wiper speed reduction, general 

Since it is assumed that the quantity of moisture on the windshield will be lower at low speeds, the automatic speed reduction circuit is actuated when the vehicle speed is reduced to v < 8 km/h.

Automatic wiper speed reduction comprises the following subfunctions:

- Function sequence for automatic wiper speed reduction, general

- Function sequence for deactivating automatic wiper speed reduction

Function sequence for automatic wiper speed reduction, general 

If the front SAM control unit (N10) recognizes a speed reduction to v < 8 km/h, the front SAM control unit switches the wiper motor (M6/1) down one stage.

Function sequence for deactivating automatic wiper speed reduction 

Actuation of the wiper motor at the speed before automatic speed reduction is accomplished by one of the following events:

- Speed v > 8 km/h

- Changing wiper speed

- Activation of the touch wiping or washing function

The vehicle speed is transmitted to the front SAM control unit by the instrument cluster (A1). The position of the combination switch is read in by the steering column tube module (N80) and transmitted to the engine compartment CAN. The central gateway control unit (N93) routes the signals to the interior CAN.