(Windshield Wiper, Function - GF82.30-P-3004GR)

MODEL 166 

up to model year 2016 

Function requirements, general 

• Circuit 15R ON

The status of circuit 15 is sent by the electronic ignition lock control unit (N73) via interior CAN (CAN B) to the SAM control unit (N10).

Wiping windshield, general 

The windshield wiping function keeps the windshield free of water or snow, for example.

The windshield wiper function is comprised of the following subfunctions:

• Intermittent wipe function sequence 
• Single wipe function sequence 
• Function sequence of wiping at specified speed 
• Function sequence for interrupting wiping during engine start 
• Wiper start suppression function sequence 
• Function sequence for wiper stop (with CODE 551 (Antitheft alarm system (ATA [EDW]))) 
• Function sequence for automatic speed reduction (except CODE 494 (USA version)) 

Intermittent wipe function sequence 

The intermittent wipe function is activated by turning the combination switch (S4) to position "1" (rain/light sensor (B38/2) low sensitivity) or to position "2" (rain/light sensor high sensitivity).

When switched from position "0" to position "1" or "2", there is an automatic wipe cycle, the so-called "Reaction wipe".

The steering column tube module control unit (N80) directly reads in the switch position of the combination switch and sends this via chassis CAN 1 (CAN E1), electronic ignition lock control unit and interior CAN to the SAM control unit. The SAM control unit sends this over the roof LIN (LIN B13) to the rain/light sensor. The rain/light sensor then calculates the frequency of the required wipe procedures on the basis of the amount of windshield wetness and sends the relevant request over the roof LIN back to the SAM control unit. The SAM control unit correspondingly actuates the wiper motor (M6/1).

The intermittent wipe function is interrupted under the following conditions:

• Activating wipe/stop function
• Activating wash function
• Activating single wipe function
• Activation of afterwipe function
• Activating wiper start suppression function
• Turning combination switch to position "0", "3" or "4"
• Blocking wiper motor
• Faulty or defective data for rain/light sensor

Single wipe function sequence 

The single wipe function can only be activated if the combination switch is set to position "0", "1" or "2". If the windshield wiper is not located in the rest position, the request of the combination switch is ignored. The single wipe function is activated by pressing the combination switch up to the detent point.

Single wipe: To wipe once, briefly push the combination switch to the detent point.

Repeated wiping: If the multifunction switch is operated for an extended period of time in position "0", wiping is performed for the operating period, however, only for a maximum of t = 30 s.

The steering column tube module control unit reads in the switch position of the combination switch directly and forwards it over the chassis CAN 1, electronic ignition lock control unit and interior CAN to the SAM control unit. The SAM control unit then actuates the wiper motor accordingly.

If the combination switch is pressed and held in the "0" position for longer than t = 30 s, the SAM control unit judges this to be a "stuck combination switch" and interrupts the single wipe function despite a pending request.

The speed at which the windshield wiper is moved during single wipe corresponds to the wiping speed in position "3" (continuous wipe at low speed).

The wash function with predefined speed is interrupted under the following conditions:

• Activating wipe/stop function
• Activating wash function
• Activation of afterwipe function
• Activating wipe interruption during engine start function
• Blocking wiper motor
• Turning the combination switch to position "0", "1", or "2"

Function sequence of wiping at specified speed 

The wipe function with predefined speed is activated by turning the multifunction switch to position "3" (continuous wipe at low speed) or position "4" (continuous wipe at high speed). The steering column tube module control unit reads in the switch position of the combination switch directly and forwards it over the chassis CAN 1, electronic ignition lock control unit and interior CAN to the SAM control unit. The SAM control unit then actuates the wiper motor accordingly.

The wash function with predefined speed is interrupted under the following conditions:

• Activation of wipe stop function (with CODE 551 (Anti-theft alarm system (ATA [EDW])))
• Activating wash function
• Activation of afterwipe function
• Activation of automatic speed reduction function (except CODE 494 (USA version))
• Turning the combination switch to position "0", "1", or "2"
• Blocking wiper motor

Function sequence for interrupting wiping during engine start 

During engine start, the SAM control inhibits actuation of the wiper motor. Any wiping procedure already started is terminated. The engine start is recognized by the transmission of the status of circuit 50. The electronic ignition lock control unit sends the status of circuit 50 via interior CAN to the SAM control unit.

Additional function requirements for wiper start suppression 

• Vehicle speed v < 3 km/h
• Combination switch in position "1" or "2"

The instrument cluster (A1) transmits the vehicle speed information to the SAM control unit via the interior CAN.

The steering column tube module control unit reads in the switch position of the combination switch directly and forwards it over the chassis CAN 1, electronic ignition lock control unit and interior CAN to the SAM control unit.

Wiper start suppression function sequence 

The wiper startup suppression is intended to prevent people from being sprayed with water from the windshield when getting in or out of the vehicle as the result of an initiated wipe operation. The windshield wipers remain in the park position despite a wipe request triggered manually or automatically. If a door is opened during a wipe procedure, the SAM control unit interrupts the actuation of the wiper motor.

Status of the front door (open or closed):

The left front door control unit (N69/1) sends the status of the left front door over interior CAN to the SAM control unit. The right front door control unit (N69/2) sends the status of the right front door over interior CAN to the SAM control unit. The SAM control unit evaluates all relevant information and interrupts actuation of the wiper motor. An already started wiping procedure is not interrupted immediately. The wipers continue to move to the park position.

The wiper start suppression is deactivated under the following circumstances:

• Vehicle speed v ≥ 3 km/h
• Combination switch in position "3" or "4"
• Single wipe or wash function activated
• Driver and passenger door closed
• Drive position "D" or "R" is engaged
• Change from circuit 15C to circuit 15R

With circuit 15R ON, no information on the current gear range is sent by the fully integrated transmission control unit (Y3/8n4) over the drive train CAN (CAN C), CDI control unit (N3/9) (diesel engine) or ME-SFI [ME] control unit (N3/10) (gasoline engine), chassis CAN 1, electronic ignition lock control unit and interior CAN to the SAM control unit. Instead, "Gear range N" is constantly sent. The current gear range is only available as of circuit 15 On. The wiper startup suppression function is not canceled by circuit15R On through the status of the gear range.

Additional function requirements for wiper stop (with CODE 551 (Antitheft alarm system (ATA [EDW]))) 

• Wipe or wash function activated
• Vehicle speed v < 3 km/h

The instrument cluster sends the vehicle speed to the SAM control unit over the interior CAN.

The steering column tube module control unit reads in the switch position of the combination switch directly and forwards it over the chassis CAN 1, electronic ignition lock control unit and interior CAN to the SAM control unit.

Function sequence for wiper stop (with CODE 551 (Antitheft alarm system (ATA [EDW]))) 

The wipe stop function prevents the wiper motor from being actuated by the SAM control unit when the engine hood is open and thus causing damage to the vehicle. If the engine hood is opened at a speed of v < 3 km/h, the SAM control unit immediately stops the wiper motor actuation.

At a speed of v > 6 km/h, the wiper stop function is deactivated, i.e. the wiper motor is actuated again from this speed onwards.

The open engine hood is detected by the status of the left engine hood contact switch (S62/43). The SAM control unit reads in the status of the left engine hood contact switch directly.

Additional function requirement for automatic speed reduction of windshield wiper system (except CODE 494 (USA version)) 

• Combination switch in position "3" or "4"

Function sequence for automatic speed reduction of windshield wiper system (except CODE 494 (USA version)) 

It is assumed that the windshield does not become as wet at slow speeds. For this reason, the SAM control unit reduces the wiper speed as soon as vehicle deceleration from v > 6 to 3 km/h is detected. The instrument cluster sends the vehicle speed to the SAM control unit over the interior CAN. The steering column tube module control unit reads in the switch position of the combination switch directly and forwards it over the chassis CAN 1, electronic ignition lock control unit and interior CAN to the SAM control unit. The SAM control unit reads in all relevant information, evaluates it and then switches the wiping speed of the wiper motor one stage down.

The speed reduction is canceled under the following conditions:

• Vehicle speed v > 6 km/h
• Changing wiper speed
• Activating single wipe function
• Activating wash function

	Electrical function schematic for windshield wiper		PE82.30-P-2051-97NAA
	Overview of system components for windshield wiper system		GF82.30-P-9996GR