Function
Function
Roof operation
The illustration shows which control modules are involved when operating the retractable roof.
Roof operation is activated via the switches on the control panel in the passenger compartment. The switches (3/25) are directly connected to the Convertible Roof Module (CRM) (4/59). The Convertible Roof Module (CRM) then transmits a signal on the CAN network to the Driver door module (DDM) (3/126) and the Passenger door module (PDM) (3/127). These, in turn, transmit another signal via their LIN network to the Left rear door module (LDM) (3/128) and the Right rear door module (RDM) (3/129).
All side windows lower at least 80 mm, to prevent friction between the roof and the windows when the roof is retracted and operated up. Thereafter the hydraulic pump and roof operation starts.
The roof is operated using an electrical and hydraulic system with the following components.
- Hydraulic cylinders
- Position sensors, used to determine the position of the hydraulic cylinders.
- Hall sensors, used to determine the position of the various metal components of the roof.
- Hydraulic pump
- Hydraulic valves, used to control the various hydraulic cylinders.
- Mechanical catches, used to lock parts of the roof in different positions.
- Electric catch motor, is an electro mechanical unit that is used to transfer mechanical force via a spring to the various catches.
Load assistance
This function increases the space in the cargo compartment when the roof is retracted and all roof sections are collected in the cargo compartment. This is to facilitate loading cargo. The maximum compartment height is then 300 mm. The cargo compartment divider must always be extended in order for the load assistance function to be activated. The function is checked by the Convertible Roof Module (CRM) and controlled from a switch located in the cargo compartment, on the right-hand side of the sill.
When the load assistance switch is activated, the roof sections start to move to their limit positions.
The switch does not need to be held pressed in for operation.
Every time the switch is activated, the direction of operation is changed. If the switch is pressed before the operation reaches its limit position, the entire operation stops immediately. The next time the switch is activated, the direction changes.
The following sequence is followed when the switch is activated: Up-Stop-Down-Stop-Up-Stop- etc.
Divider cargo compartment
The cargo compartment is divided into two sections by a divider. The compartment above the divider houses the roof components. The compartment beneath is always available for luggage. The divider must always be extended in order for the load assistance function to work. In order for the Convertible Roof Module (CRM) to know whether the divider is extended and connected, a Hall sensor is located there to read off the position.
Short-drop
To prevent interference between roof sections and windows, all side windows are lowered 80 mm from their uppermost positions (completely closed) when operating the roof. This function is known as short-drop.
The function is also used when opening and closing the doors. The windows are lowered or raised by 4 mm so that they are inside the rubber trim when the doors are closed
The Passenger door module (PDM), Driver door module (DDM), Left rear door module (LDM) and Right rear door module (RDM) receive a message from the Convertible Roof Module (CRM) via the CAN network to start a short-drop at roof operation.
If the window is already in a lower position than the short-drop position, this function is ignored. During the time that short-drop is active, all other window operations are disengaged.
Deactivating the defrost for the rear window
When the roof is completely open and folded up in the cargo compartment, the defroster is deactivated and the power of the blower fan are reduced. The Climate control module (CCM) checks this function on command from the Convertible Roof Module (CRM) via a message on the CAN network.
Speed restriction
The roof can only be operated when the vehicle is traveling at speeds below 2 km/h.
If the speed exceeds 2 km/h during the time the roof is being operated, the entire operation stops and a warning sound signal starts from the Driver information module (DIM).
The signal for the vehicle's speed is obtained from the Central electronic module (CEM).
Text message in the Driver information module (DIM)
When the roof is being operated, the driver can see the status of the roof at all times in the form of a text message in the Driver information module (DIM).
Sound parameters
The Convertible Roof Module (CRM) transmits the position of the roof out to the CAN network to the Infotainment control module (ICM) so that it can set the necessary sound parameters.
Low voltage
When the Central electronic module (CEM) signals a low battery on the CAN network to the Convertible Roof Module (CRM), it is not possible to operate the roof.
Hint: It is possible to close the roof and lower load assistance once in the event of low battery voltage.
The Convertible Roof Module (CRM) also measures the voltage internally to prevent operating the roof when voltage is low.
Operation in the event of a roof fault
Operation in the event of a roof fault is a function that makes roof operation (opening, closing and load assistance) possible even if certain sensors signal faults.
The function can only be activated when CAN communication with the Convertible Roof Module (CRM) works. Other requirements for roof operation, such as temperature in the hydraulic pump, supply voltage and the vehicle's speed still apply.
In the event of operating the roof with a non-functioning sensor, a warning sound signal is sounds from the Driver information module (DIM) and a text message is displayed. If the operating button is then released and pressed again within 5 minutes, the roof continues to operate, after 2 seconds, at the same time as the audible signal sounds. If roof operation, in the event of a roof fault, temporarily stops, keep the button depressed so that the roof continues its operation. If the load assistance function is used in the event of roof fault operation, the roof sections can only be lowered.
Lockable storage compartment and ski hatch
There are four lockable storage compartments within the vehicle. When the vehicle is locked, the storage compartments are also locked. The compartments are locked by their own electric motors. These are located in each door, one on each side in the rear seat. There is also an electric motor that locks the ski hatch in the backrest in the rear seat. The motors are connected in parallel and activated when voltage is supplied to one of the terminals on the Convertible Roof Module (CRM). To change locking to unlocking, the polarity on the output terminals in the control module is changed.
These electric motors cannot be diagnosed and the driver does not receive an indication if any of these electric motors are faulty.