LEMON Manuals: Even more car manuals for everyone
Home >> Mercedes Benz >> 2017 >> GLS450 >> Repair and Diagnosis >> Electrical >> Motors, Switches, Relays >> Electrical System - Body - 166 Chassis 2 Of 8 >> Basic Knowledge >> Windshield Wiper, Function >> Windshield Wiper, Function - GF82.30-P-3004GN

Windshield Wiper, Function - GF82.30-P-3004GN

Model 166 

as of model year 2016 

Model 292 

Function requirements, general 

IMPORTANT The electronic ignition lock control unit (N73) sends the status of circuit 15 over the 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 

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

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

The steering column tube module control unit (N80) directly reads in the 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 via roof LIN (LIN B13) to the rain/light sensor with additional functions. The rain/light sensor with additional functions then calculates the frequency of the required wipe procedures on the basis of the amount of windshield wetness and sends the relevant request via 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:

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 position of the combination switch directly and forwards it via 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.

IMPORTANT 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 single wipe 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 multifunction switch to position "3" (continuous wipe at low speed) or position "4" (continuous wipe at high frequency). The steering column tube module control unit reads in the position of the combination switch directly and forwards it via 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:

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 

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

IMPORTANT The steering column tube module control unit reads in the position of the combination switch directly and forwards it via 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.

The left front door control unit (N69/1) or the right front door control unit (N69/2) transmits the relevant status via the interior CAN to the SAM control unit. The SAM control unit reads in all relevant information, evaluates it 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:

Information about the current gear range is transmitted by the fully integrated transmission control unit (Y3/8n4) via the drive train CAN (CAN C), the CDI control unit (N3/9) (with diesel engine) or the ME-SFI [ME] control unit (N3/10) (with gasoline engine) or the powertrain control unit (N127) (in model 166.063), chassis CAN 1, the electronic ignition lock control unit and the interior CAN to the SAM control unit.

IMPORTANT With circuit 15R ON, "gear range N" is constantly transmitted. 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 wipe stop 

Function sequence for wipe stop 

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 status of the engine hood is monitored by the following components that are read in directly by the SAM control unit:

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

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

The SAM control unit reads in all of the relevant information, evaluates it and interrupts actuation of the wiper motor via the roof LIN.

Additional function requirement for automatic speed reduction of windshield wiper system (without CODE 494 (USA version)) 

Function sequence for automatic speed reduction of windshield wiper system (without 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 km/h to v < 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 position of the combination switch directly and forwards it via 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:

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