GF77.30-P-0001RI Vario Roof (VD), Function
GF77.30-P-0001RI Vario Roof (VD), Function
- except CODE (P99) Special model "AMG Black Series"
- refinement package
- as of model year 09
Function requirements, general
^ No engine start (circuit 50 OFF)
^ Status of Vario roof recognized (determination of Vario roof position)
^ Temperature of RVC [UVS] hydraulic unit (A7/5) in valid range for corresponding actuation direction and type of actuation.
^ Speed signal < 5 km/h
^ Trunk lid closed
^ Luggage compartment separation closed
Function description for Vario roof, general
The Vario roof is opened and closed hydraulically. A pump in the RVC [UVS] hydraulic unit generates the required working pressure and the hydraulic cylinders actuate the Vario roof mechanism. The Vario roof is controlled by the RVC [UVS] control unit (N52). It evaluates the positions of the limit switches and side windows and switches the solenoid valves (Y55/1y1to Y55/1y6) accordingly for control of the hydraulic cylinders.
The six solenoid valves are consolidated to form the RVC [UVS] valve block (Y55/1) and are bolted to the RVC [UVS] hydraulic unit (A7/5).
The Vario roof is controlled with the Vario roof switch (N72s16) or the transmitter key (A8/1).
On USA version code (494) the side windows can only be closed with the power window switches. For this purpose, the side windows must be moved up with the power window switches after the Vario roof is closed.
The Vario roof control comprises the following partial functions:
^ Automatically raising/lowering the roll bar
^ Automatic raising/lowering of the side windows to the short stroke position
^ Automatic opening/closing of the rear side windows
^ Trunk lid remote release
^ Opening of the trunk lid opposite to direction of travel
^ Acoustic warning signal from instrument cluster
^ Monitoring movement of Vario roof
^ Stop function
^ Relocking
^ Convenience closing/opening with transmitter key
^ Load assist
^ Hydraulic system
Further partial functions are described in separate documents:
^ Open Vario roof
^ Close Vario roof
Automatically raising/lowering the roll bar
In order to avoid a collision with the Vario roof, the roll bar is stowed during operation of the Vario roof. When the Vario roof has moved to a locked end position, it is returned to its original position. The RVC [UVS] control unit (N52) disables actuation of the roll bar while the Vario roof is being operated.
Automatic raising/lowering of the side windows to the short stroke position
The power windows are actuated by means of CAN messages from the RVC [UVS] control unit to the door control unit in question. The CAN message from the RVC [UVS] control unit causes the window to roll down to the short stroke position. This means that during operation of the Vario roof, all window functions can be performed only as far as the short stroke position.
Automatic opening/closing of the rear side windows
The rear side windows are actuated and their positions are monitored directly via the RVC [UVS] control unit. When the Vario roof is actuated, the rear side windows are opened fully.
Trunk lid remote release
The trunk lid remote release is inhibited by the RVC [UVS] control unit as long as the Vario roof is not in a locked end position.
Moreover, the trunk lid lock is actively locked by the pneumatic controller unit with combined functions (A37) if not already locked. After the Vario roof reaches a locked end position, the trunk lid reassumes its previous status.
Opening of the trunk lid opposite to direction of travel
The trunk lid is connected to the tubular frame by the two 7-joint hinges. The tubular frame opens the trunk lid opposite to the direction of travel so that the Vario roof can be stowed in the trunk.
The latch striker for the trunk lid lock is also attached to the tubular frame.
Acoustic warning signal from instrument cluster
- If the vehicle is in motion and the top is not properly locked, a warning signal sounds for 10 s. After expiration of this period of time, the gong can only be armed again by:
A change from ignition OFF to ignition ON
A change in the limit switch constellation
Actuation of Vario roof switch (N72s16)
Monitoring movement of Vario roof
The Vario roof operating sequence is stored in a sequence table for each direction of motion, which is compared with a search function (determines the current position of the Vario roof). If these values do not coincide, either an emergency operation is performed or the Vario roof sequence is interrupted and an error message is sent to the instrument cluster, depending on the severity of the error which has occurred.
If the Vario roof operating sequence is interrupted, the stop function is activated immediately, moving the Vario roof to the end position in a controlled manner.
Abort conditions
- Release Vario roof switch (N72s16)
- Ignition OFF
- Low voltage in vehicle power supply
- Vehicle speed V>5 km/h
- Trunk lid rotary tumbler and lock pawl opened
- Trunk partition not closed (applies only for opening of Vario roof)
- Roll bar crash deployment active
- Interrupt conditions resulting in damage or exceeding actuating request time
Stop function
If the operating sequence is interrupted and the Vario roof is not in a confirmed end position, the stop function becomes effective. It holds the Vario roof hydraulically in the current position for t=7 min. If the stop function cannot be revoked by this time, the Vario roof moves to the nearest mechanical end position under its own weight with hydraulic damping.
Relocking
If the Vario roof is not completely locked following actuation, the "Subsequent locking" function can be activated, whereby here, the power windows are not actuated in contrast to the regular Vario roof sequence.
It is also possible to subsequently lock the convertible top while driving.
For this purpose actuate Vario roof switch (N72s16) in the "Open convertible top" direction with the convertible top open or in the "Close convertible top" direction with convertible top closed.
Relocking is accomplished when
- the Vario roof is in the locked end position.
- from a locked end position the right tubular frame lock limit switch (S118/2) and/or Vario roof locked limit switch (right rotary tumbler) (S69/2) or Vario roof lock limit switch (left rotary tumbler) (S69/3) change their status without the Vario roof switch being actuated.
- after expiration of a defined period of time for the corresponding step when an input factor has not reached the target value.
Convenience closing/opening with transmitter key
Function requirements
- Terminal 15C"OFF"
- Voltage not to high or too low
- Trunk lid and locking pawl closed (CAN message from rear SAM control unit (N10/8))
- Trunk partition closed (CAN message from pneumatic control unit multifunction (A37))
- Crash actuation of roll bar not activated
- Press "Lock/unlock" button on transmitter key (A8/1) for longer than 1 s and hold down
- Actuation request from transmitter key (A8/1) until Vario roof is completely open or closed (CAN message from door control unit (N69/1 or N69/2)
The vehicle is not relevant here.
Comfort closing function
When the "Lock vehicle" button on the transmitter key is pressed for longer than 1 s, the Vario roof comfort closing signal is transmitted.
The signal is received by the left front IR receiver unit (A26/1) or right front IR receiver unit (A26/2). If the function requirements are fulfilled, the corresponding left door control unit (N69/1) or right door control unit (N69/2) transmits the command for comfort closing to the interior compartment CAN.
The RVC [UVS] control unit (N52) receives the CAN message to "Comfort closing" and then actuates the RTC hydraulic unit (A7/5), which closes the Vario roof.
If the "Comfort closing" actuation request is transmitted via the transmitter key (A8/1) again after the Vario roof is closed and locked, all four side windows are closed rather than the relocking feature becoming active (not on USA version, code (494)).
Comfort opening function
The comfort opening function operates analog to the comfort closing function, however in the reverse order.
On USA version code (494) the front side windows remain open during comfort opening.
The relocking function is also replaced by opening all four side windows during comfort opening
Abort conditions
- After the button on the transmitter key (A8/1) is released, the Vario roof operation is interrupted at any time for safety reasons (stop function).
- Roll bar crash deployment active
- Overtemperature in RTC hydraulic unit (A7/5) (warning signal in instrument cluster)
It is not possible to open or close the Vario roof with the comfort closing feature using the KEYLESS-GO chipcard (A8/2).
Load assist
Function requirements
- Trunk lid lock rotary tumbler open
- Vario roof closed in locked end position
- Crash deployment not activated
- Roll bar switch (N72s17) not actuated.
- Luggage compartment separation closed
- Trunk lid opened
The load assist allows free access to the trunk when the Vario roof is closed and locked in the trunk.
When the roll bar is in an intermediate position, it is moved up for the load assist function.
When the Vario roof is opened two mechanical brackets on the left and right prevent the trunk lid from closing at the 7-joint hinges on the trunk lid.
Move load assist up/down
- By actuating load assist switch (S114).
When the load assist is in an intermediate position and the load assist switch (S114) is actuated, the load assist is always moved in the direction opposite to the last time it was actuated.
Abort conditions
- If the trunk partition is opened and closed again while moving the load assist up, the upward motion is interrupted immediately.
- If the trunk partition is opened while moving the load assist down, the load assist is moved back up immediately.
- If it recognized that the trunk lid being closed while the load assist is being moved up or down the motion of the load assist is stopped immediately.
Hydraulic system
Function requirements
- RTC hydraulic unit (A7/5) in valid temperature range
Open Vario roof from closed non-actuated state:
Enable <75 °C
Inhibit/interruption >85 °C
Subsequently close or relock Vario roof:
Enable < 85 °C
Disable/Interrupt > 90 °C
- All solenoid valves functioning (self-test by RTC control unit (N52))
- All movements are performed in a predefined time window (stored in the RTC control unit for each sequence).
Abort conditions
- Malfunction in one or more solenoid valves
If a solenoid valve responsible for the function stop is defective, the function stop is not started.
If a new Vario roof actuation is received when an error is currently recognized, the defective solenoid valve is switched on and off three times to verify the error.
If the error remains present, the Vario roof request is rejected and a warning message is transmitted to the instrument cluster (A1). If the defective inputs are signaled as fault-free, the Vario roof operation is accomplished.
