Electric panoramic sliding sunroof, function - GF77.20-P-0003FL

MODEL 212 with CODE 413 (Panoramic glass roof with top sliding roof) 

Fig 1: Electric Panoramic Sliding Sunroof Block Diagram

Courtesy of MERCEDES-BENZ USA

Function requirements, general 

• No consumer shutoff by on-board electrical system management
• No overvoltage or undervoltage
• Transport mode not activated (as of 1.6.12)

Detailed information on the operating state of the transport mode is given in the separate function description "Energy management, function".

Electric panoramic sliding sunroof, general 

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 control is performed via the panoramic sliding roof switch in the electronic circuitry of the overhead control panel.

The front and rear roller sun blinds can only be opened and closed together.

Thermal protection:

The panoramic sliding sunroof motor and the panoramic sliding sunroof roller sun blind motor are protected against thermal overload by a software thermal protection in the panoramic sliding roof control module. This temperature in the motors is calculated in consideration of the voltage, current and duration of actuation as well as outside temperature.

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.

The panoramic sliding sunroof can also be operated using the convenience features, which allow it to be opened and closed centrally together with the side windows from one control point.

The comfort functions are described in the partial function "Convenience feature (CF), function" within the function description "Theft protection and locking function".

The electric sliding roof panoramic function comprises the following partial functions:

• Function sequence for position monitoring and blockage detection 
• Function sequence for normalization 
• Function sequence for opening/closing roller sun blinds 
• Function sequence for opening/closing panoramic sliding sunroof 
• Function sequence for anti-pinch protection 
• Function sequence for rain closing 

Additional function requirements for position monitoring and blockage detection 

• Circuit 15R ON or run-on time active (up to t = 5 min after circuit 15R OFF, with front doors not yet open)
• Activated actuation of panoramic sliding roof

The electronic ignition lock control unit sends the status of circuit 15 to the panoramic sliding roof control unit via the interior CAN. The status of the front door (open or closed) is sensed by the front door rotary tumbler switches. The left front door control unit reads in the status of the left front door rotary tumbler switch and transmits it to the panoramic sliding roof control module via the interior CAN. The right front door control unit reads in the status of the right front door rotary tumbler switch and transmits it to the panoramic sliding roof control module via the interior CAN.

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 following sensors:

• Hall sensor 1, panoramic sliding roof
• Hall sensor 2, panoramic sliding roof
• Hall sensor 1, panoramic sliding roof roller sun blind
• Hall sensor 2, panoramic sliding roof roller sun blind

The Hall sensors are positioned on the shafts of the panoramic sliding roof roller sun blind drive unit and panoramic sliding roof motor offset by 90°. The position of the panoramic sliding roof and the roller sun blinds is determined and monitored by counting the Hall sensor pulses. The zero position is set by normalization. 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 = 160 ms during an adjustment request. If blockage is detected in the closing direction, actuation of the of the roller sun blind motor and the panoramic sliding roof motor is interrupted and reversing is started. If blockage is detected in the opening direction, actuation of the roller sun blind motor and panoramic sliding sunroof motors is aborted.

Additional function requirements for normalization 

• Circuit 15R ON or run-on time active (up to t = 5 min after circuit 15R OFF, with front doors not yet open)
• Roller sun blinds or panoramic sliding roof denormalized
• 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

Function sequence for normalization 

Manually close roller sun blinds and panoramic sliding sunroof with panoramic sliding roof switch until the mechanical stop is reached. Then press the panoramic sliding roof switch again for min. t = 1 s so that the panoramic sliding roof control unit recognizes blockage and sets corresponding location counter to zero.

Denormalization is performed under the following conditions:

• With circuit 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 the defined Hall sensor signal sequence is faulty
• If the positions of the roller sun blind and panoramic sliding sunroof are implausible relative to each other

The position of the panoramic sliding sunroof and the roller sun blind cannot be determined in the denormalized state. The function is then restricted to manual opening and closed in increments of t = 0.5 s.

Additional function requirements for opening/closing of roller sun blinds 

• Circuit 15R ON or run-on time active (up to t = 5 min after circuit 15R OFF, with front doors not yet open)
• Panoramic sliding roof closed
• Roller sun blinds normalized
• Valid reference data present for anti-pinch protection of roller sun blinds

Function sequence for opening/closing roller sun blinds 

The roller sun blinds can be opened and closed manually or automatically.

The roller sun blinds can be opened and closed manually by actuating the panoramic sliding roof switch to the first catch for the time the request is present. When the panoramic sliding roof switch is actuated beyond the first catch, the roller sun blinds are completely opened and closed automatically.

The panoramic sliding roof control unit directly reads in the status of the panoramic sliding roof switch and actuates the roller sun blind motor according to the selected actuation direction. The anti-pinch protection function is active during closing.

Additional function requirements for opening/closing panoramic sliding sunroof 

• Circuit 15R ON or run-on time active (up to t = 5 min after circuit 15R OFF, with front doors not yet open)
• Roller sun blinds open
• Panoramic sliding sunroof normalized
• Valid reference data present for anti-pinch protection function of panoramic sliding sunroof

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 sliding sunroof 

The panoramic sliding sunroof can be opened and closed manually or automatically.

The panoramic sliding sunroof can be opened and closed manually by actuating the panoramic sliding roof switch to the first catch for the time the request is present. When the panoramic sliding sunroof switch is actuated beyond the first catch, the panoramic sliding sunroof is completely opened and closed automatically.

The panoramic sliding roof control unit directly reads in the status of the panoramic sliding sunroof switch and actuates the panoramic sliding sunroof motor according to the selected actuation direction. The anti-pinch protection function is active during closing. The anti-pinch protection is active within a limited range during opening (protection against pinching of glass cover rear edge/basic roof carrier or roof railing). Automatic opening and closing of the panoramic sliding sunroof is interrupted when the panoramic sliding sunroof switch is actuated again.

Additional function requirements for anti-pinch protection 

• Circuit 15R ON or run-on time active (up to t = 5 min after circuit 15R OFF, with front doors not yet open)
• Panoramic sliding roof or roller sun blind normalized
• Valid reference data for anti-pinch protection present

Function sequence for anti-pinch protection 

Anti-pinch protection operates by comparing the current rotational speed 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 difference exceeds a certain limit value during a closing operation, this is detected as a pinching of the panoramic sliding sunroof control unit.

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 changes in the rpm resulting from increased sluggishness (e.g. dirt in the mechanical system).

If blockage is detected during opening, the panoramic sliding sunroof as well as the roller sun blind are stopped only. During closing, the panoramic sliding sunroof and the roller sun blinds are stopped when pinching is recognized 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 closing procedure.

Additional function requirements for rain closing 

• Circuit 15R OFF or vehicle locked
• Roller sun blinds open
• Panoramic sliding sunroof normalized
• Valid reference data for anti-pinch protection present
• Panoramic sliding roof opened in sliding position

Function sequence for rain closing 

Moistening the windshield is recognized by the rain/light sensor. The SAM control unit reads in the status of the rain/light sensor via the wiper/inside mirror LIN and transmits it to the panoramic sliding sunroof control unit via the 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.

Moreover, rain closing is performed if the run-on time (t = 6 h) has expired or the voltage or temperature is no longer within the operating range 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]).