Audi A5 - Page 15

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Sensorless position recognition (SLP)
The door control units in the new Audi A5 do not
use Hall sensors for window glass position recogni-
tion. For the first time, the A5 uses the so-called
sensorless position recognition system (SLP), allow-
ing the previously used Hall sensor to be dispensed
with.
The sensorless position recognition system meas-
ures the harmonic content of the electrical current
drawn by the window regulator motor. The speed of
the window regulator motor and the actual window
glass position are determined from this informa-
tion.
393_027
Ter m i n al 3 0
Door control unit,
driver side
J368
Convenience CAN bus
Window
regulator
motor
The harmonic content is due to the continuous reversal in the polarity at the capacitor of the window regula-
tor motor.
The harmonic content measurement and analysis are also used to provide anti-pinch protection. Each revolu-
tion of the motor produces eight harmonics.
Convenience fold-back
The "convenience door mirror fold-back" feature is
optional on the A5. The driver can specify in the CAR
menu on the MMI whether the door mirrors auto-
matically fold back or not after locking the vehicle.
Accordingly, the door mirrors return automatically
to their initial position after "ignition "on"".
Note: A shunt is a very small resistance which is used for the measurement of electrical current.
The voltage drop across the shunt is measured by the control unit. The electrical current is calculated from the
measured voltage.