GF82.30-P-0003RI Wiper System (WSA), Function

GF82.30-P-0003RI Wiper System (WSA), Function

General function requirements
^ C. 15R On

Wiper system (WSA), general
The WSA controls windshield wiping and washing.

The WSA function comprises the following subfunctions:
^ Brake wiper motor (M6/1) function sequence
^ Wiper motor antilock device function sequence

Further partial functions are described in separate documents:
^ Function sequence for wiping windshield, function
^ Function sequence for wiper start suppression function
^ Automatic speed reduction of wiper system, function
(without code (494) USA version)
^ Heating wiper support, function
^ Windshield washer, function
^ Headlamp cleaning system, function
^ Washer nozzle/washer nozzle hose heater function
(with code (875) Heated windshield washer system)

Brake wiper motor function sequence
If the driver SAM control unit (N10/10) detects the actuated wiper cam and:
- the combination switch (S4) is in rest position or
- The combination switch is in position "1" and an interval is to elapse or
- afterwiping has been completed,
then the wiper motor is short-circuited using a field effect transistor.

Wiper motor antilock device function sequence
Blocking of the wiper motor is detected by the driver SAM control unit by means of the missing wiper cam signals during wiper actuation.

If the wiper cam signal is missing when wiping in Stage 2 for longer than t = 4 s, the driver SAM control unit then switches the wiper motor back to stage 1. If the signal remains missing for another t = 8 s, then the driver SAM control unit switches the wiper motor off. If a signal is received from the wiper cam again during this period of t = 8 s, the wiper motor is switched back up to stage 2.

The driver SAM control unit switches the wiper motor off when wiping in stage 1 if the wiper cam signals are missing for more than t = 12 s.

If the corresponding function is requested again by pressing the combination switch or if circuit 15R is switched on again, the antilock device is canceled.