GF82.35-D-3001H Rear Window Washer, Function

GF82.35-D-3001H Rear Window Washer, Function

- with CODE (W78) Window tailgate/hinged rear door with wipe/wash system

The "rear window wash" function is activated as from "circuit 15R ON" over the rear wiper switch (S144s5) in the combination switch (S144).
The rear wiper switch has 4 positions:
- Washing as touch stage, top
- Zero position
- Intermittent wipe
- Washing as touch stage, down

Turning and holding the rear wiper switch in the combination switch upwards out of the "zero position" activates the "wash" function for as long as the switch is operated and starts the "wipe" function.

Turning and holding the rear wiper switch in the combination switch out of the "intermittent wipe" downwards once position activates the "wash" function for as long as the switch is operated and starts the "wipe" function.
The rear end washer fluid pump (M5/3) is actuated for a maximum t = 15 s. After releasing the rear wiper switch, the rear wipers run another 2 times. With "circuit 15R OFF", the rear wipers remain in their current position. If the status "circuit 15R ON" is activated again, then the rear wipers are moved back to their park positions (completion of wiping).

The rear wiper switch signals are read in by the MRM control unit (N80) and forwarded to the Controller Area Network bus Class B (interior) (CAN-B).
The SAM control unit reads in the signals of the following components:
- Rear wiper switch
- Left rear-end door switch (S166/3)
- Right rear-end door switch (S166/4)
- Backup lamp switch (S16/2)

The SAM control unit (N10) reads in these signals over CAN-B and actuates the following components:
- Rear washer fluid pump
- Left rear-end door wiper motor (M6/10)
- Right rear-end door wiper motor (M6/11)

The "rear window wash" function has priority over the "backup wipe" function. This in turn has priority over the "rear window intermittent wipe" function.

Function with open door
If the rear door is opened at v = 0 km/h and the rear window WSA is active (signal over left and right rear-end door switches), then the left and right rear-end door wiper motors are deactivated.
If the rear-end door is closed or at v > 0 km/h and with an open rear- end door, the left and right rear-end door wiper motors are activated again.

Back-up wiping function
Back-up wiping is activated when the reverse gear is engaged for t > 5 s and the windshield WSA is activated. A complete washing cycle is performed first, i.e. the rear end washer fluid pump is actuated for t = 300 ms and the rear wipers perform 3 afterwipes.
After this, the "rear window intermittent wipe" function of the rear window WSA is activated.

Washer fluid supply
The spray nozzles of the rear window WSA are supplied with washer fluid by the rear end washer fluid pump. The rear end washer fluid pump is located on the windshield washer fluid reservoir.
The windshield washer fluid reservoir has a capacity of 7 l. If a signal is sent by the windshield washer fluid level indicator switch (S42) indicating that the windshield washer fluid reservoir is only 1/3 full, then the multifunction display in the instrument cluster (A1) shows the message "Check washer fluid level".
When the windshield washer fluid reservoir is empty, the washer fluid level indicator lamp (A1e28) in the instrument cluster lights permanently.