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GF77.20-P-0003CW Electric Panorama Sliding Roof, Function



GF77.20-P-0003CW Electric Panorama Sliding Roof, Function
- with CODE (413) Panoramic glass roof with top sliding roof
- up to model year 08


General information
The front section of the panoramic sliding sunroof can be opened in the tilt or slide position. The roller sun blinds are first retracted if they were in the extended position.
The front and rear roller sun blinds can only be opened and closed together.
Operation is accomplished with the panoramic sliding roof switch (N70/3s1) in the overhead control panel electronic system (N70/3).

The panoramic sliding sunroof can also be operated using the convenience features, which allow it to be opened and closed centrally together with the windows from one control point. These convenience features are described separately in the convenience feature (CF) function.

The function of the panoramic sliding roof comprises the following subfunctions:
^ Open/close roller sun blind
^ Open/close panoramic roof
^ Rain closing (with code (345) Rain sensor, not United States of America)
^ Anti-pinch protection
^ Position monitoring and blockage detection
^ Normalizing
^ Denormalization
^ Thermal fuse

Function requirements
^ C. 15R On
^ Run-on time active (up to t = 5 min. after circuit 15R Off, if front doors are not yet open)
^ No overvoltage or undervoltage
^ Anti-pinch protection functioning properly
^ Panoramic sliding roof and roller sun blind functioning properly

The status of the circuit is stored by the electronic ignition lock control unit (N73) on the interior CAN. The status of the front doors is recognized by the left front door lock (A85) or the right front door lock (A85/1), read in by the left front door control unit (N69/1) or right front door control unit (N69/2) and stored on the interior CAN.

Open/close roller sun blind

Additional function requirements
^ Panoramic sliding roof closed
^ Roller sun blinds normalized

Function sequence for opening/closing roller sun blinds
Actuation of the panoramic sliding roof switch is read in by the panoramic sliding roof control module (A98). It actuates the panoramic sliding roof roller sun blind motor (M12/5m1) according to the actuation.n.
When the switch is actuated to the first catch point, the adjustment takes place for as long as the request is maintained.
When the switch is actuated beyond the first catch point, the sliding roof is moved to the corresponding limit stop.
The anti-pinch protection function is active during closing.

Open/close panoramic roof

Additional function requirements
^ Roller sun blinds open
^ Panoramic sliding sunroof normalized

If the roller sun blinds are closed, these are first fully opened before the panoramic sliding sunroof is actuated.

Function sequence for opening/closing panoramic roof
Actuation of the panoramic sliding roof switch is read in by the panoramic sliding roof control module. it actuates the integrated panoramic sliding roof motor (A98m1) according to the actuation. When the switch is actuated to the first catch point, the adjustment takes place for as long as the request is maintained.
When the switch is actuated beyond the first catch point, the sliding roof is moved to the corresponding limit stop.
The anti-pinch protection function is active during closing.

Automatic adjustment of the panoramic sliding roof is aborted if the panoramic sliding roof switch is actuated again.

Detection of switch signals
Actuation is detected once the panoramic sliding roof switch is actuated without interruption for t = 40 ms ±10 ms. The maximum activation time is t ≥20 s. After t ≥60 s the system recognizes that the panoramic sliding roof switch is "stuck".
The function can only be performed again using the panoramic sliding roof switch once the rest position is detected again.

Rain closing

Function requirements
^ Circuit 15R OFF or vehicle locked
^ Panoramic sliding roof opened in sliding position

Function sequence for rain closing
Rain closing is actuated as follows:
^ Moistening the windshield is recognized by the rain/light sensor (B38/2).
^ Run-on time expired (t = 6 h)
^ Voltage or temperature no longer within permissible range of rain/light sensor (U = 10 V to 15 V) or (T = 5° C to 85° C) respectively

The front SAM control unit with fuse and relay module (N10/1) transmits the request to the panoramic sliding roof control module via interior CAN. It actuates the panoramic sliding roof motor. The panoramic sliding roof is adjusted to the tilt position.

Monitoring is then no longer performed.

Alarm triggering by interior protection (with code (882) Interior monitoring (only with ATA [EDW]) is suppressed during rain closing to prevent undesired triggering of the anti-theft alarm system (ATA [EDW]).

Function sequence for anti-pinch protection
Anti-pinch protection operates by comparing the current power consumption of the panoramic sliding roof motor or roller sun blind motor with the power consumption recorded during a teach-in run or adaptation. If this comparison exceeds a certain limit value during a closing operation, this is detected as a blockage by the panoramic sliding roof control module.

Teach-in mode: The panoramic sliding roof and the roller sun blinds are moved through all closing operations in the normalized state. The panoramic sliding roof control module adapts to change in the power consumption resulting from increased sluggishness (e.g. dirt in the mechanical system).

If blockage is detected during opening, the panoramic sliding roof as well as the roller sun blind are stopped only. During closing, the panoramic sliding roof and the roller sun blinds are stopped and then reversed (moved in opposite direction).

Special case, manual closing:
If the panoramic sliding roof switch is again actuated in the closing direction within t = 2 s after reversing, greater force is applied. The anti-pinch protection function is deactivated for the next attempt.

Function sequence for position monitoring and blockage detection
Position monitoring is performed by the panoramic sliding roof control module by evaluation the signals from the:
^ Hall sensor 1, panoramic sliding roof (A98b1)
^ Hall sensor 2, panoramic sliding roof (A98b2),
^ Hall sensor 1, panoramic sliding roof roller sun blind (M12/5b1)
^ Hall sensor 2, panoramic sliding roof roller sun blind (M12/5b2)

The Hall sensors are positioned on the shafts of the panoramic sliding roof and panoramic sliding roof motor offset by 90°. The position of the panoramic sliding roof and the roller sun blinds are determined and monitored by counting the Hall sensor pulses. The zero position is set by synchronization.
The zero position is the position at which the panoramic sliding sunroof and roller sun blinds are closed.
Blockage is detected if signals are no longer detected from the Hall sensors for a period of t = 350 ms.
If a blockage is detected, actuation of the roller sun blind motor and the panoramic sliding roof motor is interrupted.

Normalization function sequence
The roller sun blinds and panoramic sliding sunroof must be a minimum distance away from the normalization position before they are actuated to the normalization position. If closed, it is necessary to actuate for min. t = 1 s in the opening direction.
Manually close roller sun blinds or panoramic sliding roof with panoramic sliding roof switch until the mechanical stop is reached and then continue to hold panoramic sliding roof switch. The signal must be present for at least t = 1 s so that the panoramic sliding roof control module detects a blockage and can set the corresponding location counter to zero.

Function sequence for denormalization
Denormalization takes place:
^ with c. 30 OFF while actuating roller sun blind motor or panoramic sliding roof motor
^ If the panoramic sliding sunroof exceeds the defined movement range by 25 motor rotations
^ If one of two Hall sensors fails for 40 signal edges
^ If both Hall sensor signals are missing for longer than t = 320 ms during roof reversal
^ If voltage is too low and panoramic sliding roof actuation is started

The position of the panoramic sliding sunroof and the roller sun blind cannot be determined in the denormalized state. The function is then limited to manual closing or opening. Actuation can only be performed in steps of t = 0,5 s each.

Function sequence for thermal protection
A thermal protection switch integrated into the roller sun blind motor and panoramic sliding roof motor protects the roller sun blind motor and the panoramic sliding roof motor against overload. The roller sun blind motor and panoramic sliding roof motor are not designed for continuous operation. They are switched off if the maximum permissible operating time is exceeded.

If the thermal protection function is triggered, actuation is disabled until the minimum cooling time has passed.
The thermal protection function does not operate during roof reversal after a blockage is detected.