GF77.20-P-0001LE Electric Tilting/Sliding Roof (SR), Function
GF77.20-P-0001LE Electric Tilting/Sliding Roof (SR), Function
- with CODE (414) Power glass tilting/sliding roof
- as of model year 09
Function requirements, general
^ C. 30 ON
^ No overvoltage or undervoltage
Electric tilting/sliding roof (SHD), general
The electric tilting/sliding roof (SHD) function allows the tilting/ sliding roof to be opened and closed.
Operation is by means of the roof switch (N70s1) in the overhead control panel control unit (N70)
The SHD is a combined tilting and sliding roof. The sliding roof function drops the SHD down and moves it backwards into the headliner, the tilting roof function raises the SHD at the rear.
There are convenience features allowing the SHD to be opened and closed from one central control point.
These convenience features are described separately in the convenience feature (CF) function.
The electric SHD function comprises the following partial functions::
^ Function sequence for SHD opening/closing
^ Function sequence for rain closing (without code (494) USA version)
^ Function sequence for anti-pinch protection
^ Function sequence for position monitoring and blockage detection
^ Function sequence for memory function
^ Function sequence for anti-wind-hum position
^ Function sequence for normalization
^ Function sequence for denormalization
^ Function sequence for thermal protection
Additional function requirements for SHD opening/closing
^ C. 15R On
^ Run-on time active
(up to t = 5 min. after circuit 15R Off, if front doors are not yet open)
The status of circuit 15R is transmitted by the EIS [EZS] control unit (N73) via interior CAN (CAN B).
The status of the front doors is defined as follows:
Model 216: The status of the left rotary tumbler switch (A85s1) is read in by the left door control unit (N69/1), the status of the right rotary tumbler switch (A85/1s1) by the right door control unit (N69/2).
Model 221: The status of the left front rotary tumbler switch (A85s1) is read in by the left front door control unit (N69/1), the status of the right front rotary tumbler switch (A85/1s1) by the right front door control unit (N69/2).
The corresponding door control unit transmits the door status via the interior CAN.
Function sequence for SHD opening/closing
The partial function is comprised of the following subfunctions:
^ Function sequence for manual SHD opening/closing
^ Function sequence for automatically opening/closing TSR [SHD] (without code (494) USA version)
Function sequence for manual SHD opening/closing
The roof system switch is actuated as far as the first catch point and this is read in by the overhead control panel control unit. It then actuates the roof system motor (M12m1) in the roof system drive unit (M12) according to the desired actuation direction as long as the request is present.
When the SR is denormalized, it can only be actuated in steps of t = 0.5 s.
Function sequence for automatic SHD opening/closing
When the roof system switch is briefly actuated past the first catch point, the SHD is automatically adjusted to the respective end position in accordance with the actuation direction. Automatic adjustment is aborted if the roof system switch is actuated again.
Detection of switch signals
Actuation is detected once the roof system 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 considers the roof system switched to be jammed. The function can only be performed again using the roof system switch once the rest position is detected again.
Additional function requirements for rain closing (without code (494) USA version)
^ Circuit 15R OFF or vehicle locked
^ SHD open in slide position
Function sequence for rain closing (without code (494) USA version)
The rain closing feature is actuated if moisture is recognized on the windshield by the rain/light sensor (B38/2)
The overhead control panel control unit reads in the signal from the rain/light sensor and actuates the roof system motor. The SHD is moved to the tilt position. Monitoring is then no longer performed.
Rain closing is still accomplished when the run-on time (t = 6 h) has expired or the voltage or temperature is no longer within the voltage range (U = 10 V to 15 V) or temperature range (T = 5 °C to 85 °C) of the rain/light sensor.
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]).
Additional function requirements for function sequence of anti-pinch protection
^ C. 15R On
^ Run-on time active
(up to t = 5 min. after circuit 15R Off, if front doors are not yet open)
Function sequence for anti-pinch protection
Anti-pinch protection operates by comparing the current power consumption of the roof system motor with the power consumption recorded during a teach-in run or adaptation.
If a certain limit value is exceeded during a closing operation, this is detected as blockage of the SHD by the overhead control panel control unit.
This involves operating all of the closing procedures of the SHD in the normalized condition. The overhead control panel control unit adapts to any change in power consumption of the roof system motor due to increased sluggishness (e.g. dirt in the mechanical components).
If a blockage is detected during an opening procedure, the SHD is simply stopped.
During a closing procedure, the SHD is stopped and then reversed (moved in the opposite direction).
Special case, manual closing:
If the roof system switch is actuated again in the closing direction within t = 2 s after the roof is reversed, greater force is applied t close the roof. The anti-pinch protection function is deactivated for the next attempt.
Additional function requirements for position monitoring and blockage detection
^ C. 15R On
^ Run-on time active
(up to t = 5 min. after circuit 15R Off, if front doors are not yet open)
Function sequence for position monitoring and blockage detection
Position monitoring is performed by the overhead control panel control unit by evaluating the signals of roof system Hall sensor 1 (M12b1) and roof system Hall sensor 2 (M12b2), which are positioned on the roof system motor axle offset at 90°.
The position of the SHD is determined and monitored by counting the Hall sensor pulses.
The zero position corresponds to the SHD position when tilted open. The zero position is set by normalization.
Blockage is detected if signals are no longer detected from the Hall sensors for a period of t = 350 ms.
Actuation of the roof system motor is interrupted in the event of a blockage.
Function sequence for memory function
The momentary position of the TSR [SHD] is stored in the overhead control panel control unit by the position recognition. The memory position is stored each time manual adjustment is terminated (after t = 0.5 s), if the position is in the permissible range between TSR [SHD] closed position and anti-wind-hum position.
When the TSR [SHD] is opened automatically, the last set and stored TSR [SHD] position is actuated. If this set TSR [SHD] position is changed by manual adjustment, the old memory position is overwritten by the current position.
The memory function can be activated over the IS tester.
Additional function requirements for anti-wind-hum position
^ Memory function deactivated
Function sequence for anti-wind-hum position
When the TSR [SHD] is in the sliding or tilt position, the anti-wind-hum position prevents disturbing wind noises at higher speeds. The anti-wind-hum position of the tilting roof is actuated when the tilting roof is opened and closed automatically. When opened or closed again, the end position is actuated.
When opened automatically the sliding roof moves to the anti-wind-hum position, if the sliding roof is between the closed TSR [SHD] position and the anti-wind-hum position. When opened or closed again, the end position is actuated.
The anti-wind-hum position can be activated over the IS tester.
Additional function requirements for normalization
^ C. 15R On
^ Run-on time active
(up to t = 5 min. after circuit 15R Off, if front doors are not yet open)
Normalization function sequence
The SHD must be opened manually to the tilt position and to the rear slide position until the mechanical stop is reached using the roof system switch and the roof system switch must be kept actuated.
The signal must be present for at least t = 1 s so that the overhead control panel control unit detects blockage of the roof system motor and can set the location counter to zero.
When normalized, the roof system motor is switched off by the overhead control panel control unit before the mechanical stop is reached during automatic opening and closing.
Function sequence for denormalization
Denormalization takes place:
- If the roof system motor is actuated with c. 30 OFF
- If the SHD exceeds the defined movement range
- If one of two Hall sensors fails for 10 signal edges
- If both Hall sensor signals are missing for longer than t = 320 ms during roof reversal
- If an SHD actuation is started simultaneously during undervoltage
The position of the SHD cannot be determined in the denormalized condition. The function is then limited to manual closing or opening.
Function sequence for thermal protection
A thermal load protection switch integrated into the roof system motor protects the roof system motor against overload. The roof system motor is not designed for continuous operation.
The roof system motor is switched off if the maximum permissible operating time is exceeded.
If the thermal protection function is triggered, the roof system motors are disabled until the minimum cooling time has passed. The thermal protection function does not operate during roof reversal after a blockage is detected.
