Windshield Washer, Function - GF82.35-S-3002TRB

Model 447.6/7 

Model 448.7 

Function requirements, general 

• "Circuit_15R_ON"

The electronic ignition lock (EZS) control unit (N73) sends the status of circuit 15 via the interior CAN (CAN B) to the signal acquisition and actuation module (SAM) control unit (N10/1).

Washing windshield, general 

The windshield wash function is comprised of the following subfunctions:

• Washing function sequence 
• Afterwiping function sequence 
• Function sequence for interrupting washing during engine start 
• Function sequence for wash stop 
• Washer fluid supply 

Washing function sequence 

The washing function is activated by pressing the combination switch (S4) in axial direction beyond the detent point.

The steering column tube module (MRM) control unit (N80) directly reads in the switch position of the combination switch and transmits this via the chassis CAN (CAN E), electronic ignition lock (EZS) control unit, and interior CAN to the signal acquisition and actuation module (SAM) control unit.

The signal acquisition and actuation module (SAM) control unit then sends the corresponding actuations via the engine compartment fuse and relay module (K40/10) to the windshield washer system pump (M5/4) and the wiper motor (M6/1).

During washing, wiping takes place with the wiper speed set on the combination switch or in stage "3".

The "washing" function is interrupted under the following conditions or after 15 s:

• Activation of the washer interruption function when the engine starts
• Activating wipe/stop function
• "Combination switch stuck" detection

After wiping function sequence 

The after wiping function is activated as soon as the combination switch is no longer activated after a wash request.

The number of afterwipe cycles depends on the combination switch actuation time:

• Actuation time < 200 ms: Afterwiping does not take place.
• Actuation time < 1 s: Afterwiping takes place once.
• Actuation time > 1 s: Afterwiping takes place three times.

Afterwiping takes place with the wiper speed set on the combination switch. When the combination switch is in the rest position, afterwiping takes place with speed "3".

The afterwiping function is interrupted or aborted under the following conditions:

• Activation of the washer interruption function when the engine starts
• Blocking of wiper motor
• Activating wash function
• Activating wipe/stop function

Function sequence for interrupting washing during engine start 

The CDI control unit (N3/36) (with engine 651.9) or the ME-SFI [ME] control unit (N3/34) (with engine 274) or the CDI control unit (N3/33) (with engine 622) sends the "Engine start, request" signal via chassis CAN, electronic ignition lock (EZS) control unit and interior CAN to the signal acquisition and actuation module (SAM) control unit. The signal acquisition and actuation module (SAM) control unit blocks the actuation of the windshield washer system pump and the wiper motor.

Any wiping procedure already started is interrupted while the engine is started and continues to run after the engine start.

Function sequence for wash stop 

If the engine hood is opened while the windshield is being washed, the signal acquisition and actuation module (SAM) control unit aborts the actuation of the windshield washer system pump. The opening of the engine hood is detected by the engine hood switch (S62/41). The signal acquisition and actuation module (SAM) control unit directly reads in the status of the engine hood switch.

If the engine hood is closed, the windshield washer system pump can be actuated again. This is also possible if the engine hood is open and the vehicle speed does not exceed 6 km/h.

The vehicle speed is sent by the instrument cluster (IC [KI]) control unit (A1/1) via the chassis CAN, electronic ignition lock control unit (EZS) and interior CAN to the signal acquisition and actuation module (SAM) control unit.

Washer fluid supply 

The spray nozzles of the "Windshield wash" system are supplied with washer fluid via the windshield washer system pump. The windshield washer system pump is located at the washer fluid reservoir.

If the windshield washer system water level indicator switch (S42) sends the signal that the washer fluid reservoir is only 1/3 full, the "Check washer fluid level!" message appears on the multifunction display (A1/1p13) of the instrument cluster (IC [KI]) control unit. The signal acquisition and actuation module (SAM) control unit reads in the status of the windshield washer system water level indicator switch directly and sends a signal via interior CAN to the instrument cluster (IC [KI]) control unit. The instrument cluster (IC [KI]) control unit transmits the signal on to the multifunction display.

When the washer fluid reservoir is empty, the "Washer fluid level" indicator lamp in the multifunction display of the instrument cluster (IC [KI]) control unit lights up continuously.

	Electrical function schematic for windshield washer	Model 448.7	PE82.35-S-2051-97VDB
		Model 447.6/7	PE82.35-S-2051-97TRB
	Overview of system components, wiper system (WSA)		GF82.30-S-9997TRA