Power Window Position Recognition, Function

Power Window Position Recognition, Function







Function
2 Hall sensors each (b1, b2) are located on each axis of the power window motors.
Each Hall sensor supplies one square-wave pulse for each rotation of the motor.
The corresponding left door control module (N69/1) or right door control module (N69/2) as well as the RVC control module (N52) detect these pauses and analyze them for detecting the direction of rotation and position.

Direction recognition
From the time difference between the pulses from Hall sensor (b1) and the pulses from Hall sensor (b2) the relevant control module recognizes the direction of rotation of the power window motor.

Position recognition
The control module counts the pulses from the 2nd Hall sensor in relation to the motor direction. The value in the position counter is increased when the windows closes. When the window opens, the value in the position counter is reduced. The upper mechanical limit stop is defined as zero position, i.e. when the window is fully closed the counter should be at zero.The zero position is set through synchronization. If the zero position is exceeded in the open direction, the count becomes negative, and thus invalid. In this case, a resynchronization is performed.