Rain Closing Function, Basic Function - GF77.20-P-1002A

Model all (CAR) except code 494 (US version) 

Overview 

This document contains information on:

• General 
• Function requirements 
• Rain closing function when vehicle is parked 
• Dynamic rain closing function (during vehicle operation) (vehicles with panoramic sliding sunroof) 

General 

The automatic rain closing function prevents rainwater from entering into the vehicle interior.

The following measures are taken when it rains:

• Open side windows are closed either completely or until only a small gap is left open.
• A sliding sunroof or panoramic sliding sunroof opened in the slide position is fully closed and raised to the tilt position (vehicles with sliding sunroof or panoramic sliding sunroof).
• A panoramic sliding sunroof fully opened in the tilt position is lowered in the event of heavy rain (vehicles with panoramic sliding sunroof).

The automatic rain closing function can be canceled by submitting another request.

The rain is detected by the rain and light sensor on the windshield or defined via the activity of the windshield wiper system.

The automatic reversing function is active during the adjustment.

Function requirements 

• The power windows are normalized.
• The sliding sunroof or panoramic sliding sunroof is normalized (vehicles with sliding sunroof or panoramic sliding sunroof).

Rain closing function when vehicle is parked 

The vehicle is considered parked when circuit 15R is OFF or when the vehicle was locked.

When the rain sets in, the system responds as follows:

• Open side windows are closed until they reach the ventilation position (vehicles without sliding sunroof and without panoramic sliding sunroof).
• Open side windows are closed completely (vehicles with sliding sunroof or panoramic sliding sunroof).
• A sliding sunroof or panoramic sliding sunroof opened in the slide position is fully closed and raised to the tilt position (vehicles with sliding sunroof or panoramic sliding sunroof).

Vehicles with interior protection

Alarm triggering by the interior protection is suppressed during rain closing to prevent unintentional triggering of the anti-theft alarm system.

Dynamic rain closing function (during vehicle operation) (vehicles with panoramic sliding sunroof) 

With the dynamic rain closing function, the raised panoramic sliding sunroof automatically lowers out of the tilt position during vehicle operation in the event of heavy rain. This prevents rain from being blown in.

The panoramic sliding sunroof lowers itself if the windshield wiper system is operated at the highest level for approx. 15 s.

	Control units
	Basic function of signal acquisition and actuation module	Model 118, 177, 243, 247 except code 494 (US version)	GF54.21-P-9895A
	Basic function of signal acquisition and actuation module at front	Model 167, 206, 223, 232, 293, 297 except code 494 (US version) Model 213, 238, 257, 290 as of model year 2021 except code 494 (US version)	GF54.21-P-9896A
	Components
	Rain and light sensor, basic function		GF54.21-P-2005A