Principle of Operation

Principle of Operation
The Soft-top module IV controls the raising and lowering of the electro-hydraulic soft-top in response to the commands from the soft-top control buttons.
Preconditions for raising/lowering that are detected directly by the Soft-top module IV:
^ Hall-effect sensor 1 for the windscreen top rail lock signals that the windscreen top rail lock is disengaged (soft-top unlocked)
^ Hall-effect sensor 2 for the windscreen top rail lock signals that the windscreen top rail lock is engaged (soft-top locked),
^ The Hall-effect sensor (for soft-top raised) on the hinge of the main pillar signals that the soft-top is raised, or
^ The Hall-effect sensor (for soft-top lowered) on the hinge of the main pillar signals that the soft-top is stowed in the stowage compartment
^ The hardtop detector signals that no hardtop is fitted
^ The microswitch of the variable size stowage compartment indicates that the stowage compartment base it at its lowest position
^ The Soft-top module IV has not detected any faults on the system as a whole during its internal system test

Other conditions that are detected indirectly by the Soft-top module IV:
^ Ignition key at position R at least
^ Window not closed
^ Vehicle stationary (road speed < 4 km/h)
^ No short circuit and no circuit break present
^ Outside temperature is not below the limit of approximately 20°C
^ Soft-top button pressed
The Soft-top module IV exchanges information via the Kbus. The Soft-top module IV monitors the Hall-effect sensors for plausibility of the signals and correct function. There are 2 Hall-effect sensors fitted to the hinge of the main pillar. There are 2 Hall-effect sensors on the front roof bow of the electroRydraulic soft-top.

Response to high/low voltage
The voltage range of the Soft-top module IV is 9 V to 16 V.

Method of operation of soft-top stowage compartment lock
The soft-top stowage compartment lock holds the soft-top in place when it is fully stowed in the compartment. When the soft-top is raised, it locks onto the windscreen top rail.

Operation of soft-top stowage compartment lock when lowering soft-top
When the electrohydraulic soft-top is fully lowered into the stowage compartment it is automatically locked in position. This is effected by the electro-hydraulic soft-top being lowered to a position in the stowage compartment where the mechanical locking mechanism engages.
The Hall-effect sensor on the hinge of the righthand main pillar signals to the Soft-top module IV that the electro-hydraulic soft-top is in the fully lowered (stowed) position. The locking latches on the electro-hydraulic soft-top are then also engaged. The locking latches are controlled by the Soft-top module IV.
When the electro-hydraulic soft-top is in the fully lowered (stowed) position, the Soft-top module IV switches the hydraulic pump off. The relay is switched off by virtue of the fact that it is no longer enabled by the Soft-top module IV.
The electrohydraulic soft-top is now fully lowered into the stowage compartment.

Operation of soft-top stowage compartment lock when raising soft-top
When the electrohydraulic soft-top is raised, the stowage compartment catch is released, the locking latches disengaged and the soft-top raised out of the stowage compartment. On the windscreen top rail, the locking latches engage and lock the electrohydraulic soft-top in position.

Operation of soft-top stowage compartment lock
The soft-top stowage compartment lock mechanism engages the latches of the fully automatic soft-top when it is fully lowered into the stowage compartment.When the fully automatic soft-top is raised, the latches are engaged in the windscreen top rail.
The fully automatic soft-top is now fully lowered into the stowage

Operation of soft-top control buttons
The soft-top control buttons for controlling the soft-top UP and DOWN actions are switches that connect to ground. Closing the connection to ground signals to the Soft-top module 4 that raising or lowering of the fully automatic soft-top has been requested.

Operation of Hall-effect sensors
The Hall-effect sensors signal the position (LOCKED or UNLOCKED) of the locking latches to the Soft-top module 4.Operation of soft-top Relays
The Soft-top module 4 controls the relays. The 2 relays for the hydraulic pump are controlled as required (for raising or lowering soft-top) by the Soft-top module 4.
The relays are wired in such a way that the hydraulic pump action is reversible. The relays are controlled by the Soft-top module 4 via High side switches. On a High side switch, the transistor connects positive through.

Soft-top latch for locking to windscreen top rail
The locking latches are closed when they locate in the windscreen top rail. The left and right locking latches are closed when they locate in the windscreen top rail. The rotation of the DC motor is transmitted to spindles. The spindles drive linkages. The action of the linkages is transmitted to the locking latches. The locking latches lock/unlock the fully automatic soft-top to/from the windscreen top rail.
The position of the locking latches is detected by Hall-effect sensors 1 and 2

Microswitch for variable size soft-top stowage compartment
The microswitch signals to the Soft-top module 4 that the stowage compartment base is at its lowest position. The Soft-top module 4 is informed by the microswitch that the movable stowage compartment base is at its lowest position. The microswitch is a make switch that connects to earth.

GM5
The general module 5 opens or closes the windows on instruction from the Soft-top module
4. The general module 5 stores the current status of trunk and window position. The general module 5 places the following information on the Kbus when it starts up:
^ Current status of trunk and windows
^ Changes to current status of trunk and windows
Examples of current status information are:
^ Window closed; window open,
^ Trunk closed; trunk open. (The signal for the trunk status is present but is not required by the Soft-top module 4)
The general module 5 receives the control commands for raising and lowering the windows from the Soft-top module 4. The Soft-top module 4 sends the control commands via the body electronics bus before and after raising/lowering the soft-top. The precondition for lowering the windows is that at least one window is closed.
If the windows are already open before the soft-top is raised/lowered, and if one of the two soft-top control buttons remains pressed (2 s) after the soft-top has been fully raised/lowered, the windows are closed. Closing of the windows is stopped as soon as either of the soft-top control buttons is released or the window mechanism detects that the window is closed (at limit of movement).

Soft-top stowage compartment lock
The locking latches are closed when the soft-top is stowed in the stowage compartment and the soft-top locked in position. As soon as the fully automatic soft-top is stowed in the stowage compartment, the locking latches close.