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Windshield wiper, function - GF82.30-P-3004CE

MODEL 204.0/2 as of model year 2009/YoM 08 

MODEL 204.3 

MODEL 204.9 

Function requirements, general 

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

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 

The intermittent wipe function is activated by turning the combination switch (S4) to switch position "1" (wiping with long interval time (without code (345) Rain sensor) or rain/light sensor (B38/2), low sensitivity (with code (345) Rain sensor)) or to switch position "2" (wiping with short interval time (without code (345) Rain sensor) or rain/light sensor, high sensitivity (with code (345) Rain sensor)).

IMPORTANT On vehicles with code (345) Rain sensor, when the following change to the switch position of the combination switch is performed, a wipe cycle is first triggered ("reaction wipe"):

The steering column tube module control unit (N80) directly reads in the position of the combination switch and transmits it to the front SAM control unit via the chassis CAN (CAN E).

On vehicles without code (345) Rain sensor, the front SAM control unit actuates the wiper motor (M6/1) accordingly via wiper/inside rearview mirror LIN (LIN 2).

On vehicles with code (345) Rain sensor, the front SAM control unit sends the switch position of the combination switch via wiper/inside rearview mirror LIN to the rain/light sensor. The rain/light sensor then calculates the required wipe frequency on the basis of the amount of windshield wetness and sends the relevant request via the wiper/inside rearview mirror LIN to the front SAM control unit. The front SAM control unit actuates the wiper motor accordingly via wiper/inside rearview mirror LIN.

The intermittent wipe function is interrupted under the following conditions:

IMPORTANT With faulty data from the rain/light sensor (with code (345) Rain sensor), the intermittent wipe function is also aborted. The wiper motor is then actuated at the defined time intervals.

Touch wiping function sequence 

The touch wiping function can only be activated if the combination switch is in switch position "0", "1" or "2". If the windshield wiper is not located in the rest position, the request of the combination switch is ignored.

Wipe once:

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

Repeated wiping:

If the combination switch is pressed for longer, wiping takes place in accordance with the duration for which it is pressed, but only for a maximum of t = 30 s.

The steering column tube module control unit directly reads in the position of the combination switch and transmits it to the front SAM control unit via the chassis CAN. The front SAM control unit actuates the wiper motor accordingly via wiper/inside rearview mirror LIN.

IMPORTANT If the combination switch is pressed in switch position "0" for longer than t = 30 s, then a "stuck combination switch" is assumed and the touch wiping function is interrupted despite the current request.

The speed at which the windshield wipers are moved corresponds to the wiping speed in switch position "3" (continuous wipe at low speed).

The touch wiping function is interrupted under the following conditions:

Function sequence of wiping at specified speed 

The wipe function with predefined speed is activated by turning the combination switch to switch position "3" (continuous wipe at slow speed) or switch position "4" (continuous wipe at fast speed).

The steering column tube module control unit directly reads in the position of the combination switch and transmits it to the front SAM control unit via the chassis CAN.

The front SAM control unit then actuates the wiper motor over the wiper/inside rearview mirror LIN accordingly.

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

IMPORTANT When the wipe function with predefined speed is active on vehicles with code (345) Rain sensor, the data of the rain/light sensor is not taken into consideration.

Function sequence for interrupting wiping during engine start 

During engine start, the front SAM control inhibits the 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 to the front SAM control unit via interior CAN.

Additional function requirements for wiper start suppression 

Wiper start suppression function sequence 

The wiper startup suppression is intended to prevent the driver or front passenger 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 wipers remain in the park position despite an actuated manual or automatic wipe request.

If a door is opened during wiping, the front SAM control unit interrupts the actuation of the wiper motor.

The instrument cluster (A1) sends the vehicle speed to the front SAM control unit over the interior CAN.

The steering column tube module control unit directly reads in the position of the combination switch and transmits it to the front SAM control unit via the chassis CAN.

The opening of the left door is recognized through the status of the left front door rotary tumbler switch (A85s1) in the left front door lock (A85).

The left front door control unit (N69/1) reads in the status of the left front door rotary tumbler switch directly and sends it to the front SAM control unit via interior CAN.

The opening of the right door is recognized through the status of the right front door rotary tumbler switch (A85/1s1) in the right front door lock (A85/1). The right front door control unit (N69/2) reads in the status of the right front door rotary tumbler switch directly and sends it to the front SAM control unit via interior CAN. The front SAM control unit reads in all relevant information, evaluates it and interrupts actuation of the wiper motor. A wiping procedure that has already started is not interrupted immediately. The wipers continue to move to the park position.

The wiper start suppression is deactivated under the following circumstances:

IMPORTANT In the event of circuit 15R On, no information is available about the current selector lever position.

The electronic selector lever module control unit (N15/5) constantly sends "selector lever position N" via drive train CAN (CAN C), CDI control unit (N3/9) (with diesel engine) or ME-SFI [ME] control unit (N3/10) (with gasoline engine) and chassis CAN to the front SAM control unit. The current selector lever position is only available as of circuit 15 On. The wiper start suppression is not canceled by circuit 15R On.

The "Clutch actuated" status is sensed by the clutch pedal switch (S40/3). The CDI control unit or ME-SFI [ME] control unit reads in the status of the clutch pedal switch directly and transmits it to the front SAM control unit via the chassis CAN.

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

Function sequence for wipe stop (with code (551) Antitheft alarm system (ATA [EDW])) 

The wipe stop function prevents the wiper motor from being actuated by the front SAM control unit with the engine hood open, thereby causing damage to the vehicle.

If the engine hood is opened at a speed of v < 3 km/h, the front SAM control unit immediately aborts the actuation of the wiper motor. The wipe stop function is deactivated at a speed of v > 6 km/h, i.e. the wiper motor is actuated again as of this speed.

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

The steering column tube module control unit directly reads in the position of the combination switch and transmits it to the front SAM control unit via the chassis CAN.

The opened engine hood is recognized by the pedestrian protection Hall sensor + ATA [EDW] engine hood switch (A38/1) (with code (U60) Pedestrian protection) or by the left engine hood contact switch (S62/43) (without code (U60) Pedestrian protection).

The rear SAM control unit with fuse and relay module (N10/2) reads in the status of the pedestrian protection Hall sensor + ATA [EDW] engine hood switch (with code (U60) Pedestrian protection) or the left engine hood contact switch (without code (U60) Pedestrian protection) directly and sends this via interior CAN to the front SAM control unit.

The front SAM control unit reads in all relevant information, evaluates this and interrupts the actuation of the wiper motor via wiper/inside rearview mirror LIN.

Additional function requirements for automatic speed reduction (without code (494) USA version) 

Automatic speed reduction function sequence (without code (494) USA version) 

It is assumed that the windshield does not become as wet at slow speeds. For this reason, the front SAM control unit reduces the wiper speed as soon as vehicle deceleration from v > 6 km/h to v < 3 km/h is detected.

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

The steering column tube module control unit directly reads in the position of the combination switch and transmits it to the front SAM control unit via the chassis CAN.

The front SAM control unit reads in all relevant information, evaluates it and switches the wiper speed of the wiper motor back by one stage via the wiper/inside rearview mirror LIN.

The speed reduction is canceled under the following conditions:

REFER TO SYSTEM WIRING DIAGRAMS Electrical function schematic for windshield wiper   PE82.30-P-2051-97FAB
  Overview of system components, wiper system (WSA)   GF82.30-P-9997CE 
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