Power Windows
Power Windows
Standard on the MINI is power operation of the Driver and Passenger windows. The Rear Quarter windows are fixed.
Purpose of the System
The purpose of the power window system is to provide for operation of both the driver and passenger door windows. No manual operation of the windows is possible.
System Components
BC1
The Body Control Module (BC1) via internal relays controls the power windows. Operation from inside the car is possible from the window switches or the interior central locking switch and from outside via the driver's door lock cylinder.
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System Components
Power Window Switches
The window switches are located in the switch pack situated in the lower part of the center console. A single connection is used to connect the switch pack to the vehicle harness.
Power Window Motor/Regulator
The Power Window Motor/Regulator is installed in the door. The motor is driven by the BC1 with current being reversed to control up/down operation. The motor and regulator are available as separate parts for service.
Interior Central Locking Switch
Located in the switch pack the Interior Central Locking Switch is involved in the convenience opening of the windows.
Door Latch Assembly
The door latches have integral micro switches for door open contacts and driver key switch lock/unlock inputs.
Inertia Switch
The inertia switch is located under the hood will advise the BC1 in case of an accident so the windows can be rolled down.
Principle of Operation
Conventional Opening/Closing
If either window switch is operated for longer than the 400 ms, the window is controlled in the conventional way. The window is operated in the open/close direction for as long as the switch is held or until the window is fully opened/closed or if an obstruction is sensed. As soon as the switch is released the window operation is terminated.
One-Touch Opening
If either window switch is operated for less than 400 ms, the system shall assume one-touch mode. In one-touch mode the window travels to the fully open position. The window can be stopped at any time by briefly pressing the relevant window switch in either direction. The motor is powered for 15 seconds and then switched off.
One-Touch Closing
One-touch closing operation is not functional in the US market.
If the driver's side window switch is operated for less than 400 ms, the system shall assume one-touch mode. In one-touch mode the window travels to the fully closed position. The window can be stopped at any time by briefly pressing the window switch in either direction. The motor is powered for 15 seconds and then switched off.
Short Drop/Raise Function
On opening the driver's or passenger's door the window is partially lowered to the clear of seal position (COS), on closing the relevant door the window will close fully up into the seal. This function aids opening and closing of the doors.
The BC1 activates the window for 150 ms to open slightly. For the close procedure the window is powered for a maximum of 600 ms or until the cut-out current is seen by the BC1.
Convenience Opening/Closing
The windows can be conveniently opened and closed from outside the car at the driver's door lock. The key must be held over in the desired position to lock the car and close the windows or unlock the car and open the windows. Operation is ceased when the key is released.
The windows can also be conveniently opened from inside the car by holding the interior central locking switch in the unlock position. Operation is ceased when the switch is released.
BC1
Based on input received the BC1 energizes the appropriate internal relay to power the window up/down. The BC1 monitors the current draw of the motor at 2 ms intervals for the first 50 ms and then at 100 ms intervals.
The peak current measured is reduced by 4A and this value is then used as the cut-out current at which the BC1 will deactivate the motor. During operation of the window motor, if no cut-out current is seen the BC1 will switch off the motor after 15 seconds.
If at any point the current exceeds 35A the BC1 will deactivate the motor immediately.
Power Window Switches
Each Power Window Switch is a two position spring loaded switch. When pressure applied to the switch in either direction is released the switch will return to a middle neutral position.
The Power Window Switches provides a switched ground signal to the BC1 requesting window activation. A momentary touch of the switch (less than 400ms) activates the one-touch operation. A longer touch of the switch (more than 400ms) signals the BC1 for conventional window operation.
Window Motor
Polarity is reversed in the BC1 to control motor operation up/down. Current draw of the motor during its entire operating range is monitored by the BC1 and the motor stopped when current or time limits are exceeded.
Interior Central Locking Switch
The Interior Central Lock Switch is a two position spring loaded switch. When pressure applied to the switch in either direction is released the switch will return to a middle neutral position.
The interior central lock switch supplies a switched ground signal to the BC1. Pressing and holding the switch in the unlock position requests convenience opening of the windows and sunroof from the BC1. The convenience opening operation lasts as long as the switch remains depressed.
Door Latch with Micro Switches
The drivers door Lock/Unlock micro switch provides a switched ground input to the BC1. Holding of the key in either the lock or lock position for longer than 1 second will request convenience opening/closing of the windows. The opening/closing operation continues as long as the key is held or until the windows are open/closed. The door position micro switches provide a switched ground signal to the BC1 indicating door position. A high signal at the BC1 indicates the door is open and a low signal indicates the door is closed.
Inertia Switch
In the event of an impact registering greater than 14G the Inertia Switch goes open. This open removes the voltage from X254 pin 21 at the BC1(J3 54-pin Natural connector) and causes the BC1 to lower the windows on a time basis of 750ms.