BMW E61 Sports Wagon 530xiT, Руководство пользователя

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DXC8+ Control Unit
The DXC8+ control unit is installed in the engine compartment essentially consists of
three components:
• Add-on control unit
• Valve block with integrated pressure sensors
• Pump motor
The newly developed changeover valves permit even more exact control in the low pres-
sure range, resulting in the following advantages:
• Reduction of control noise
• Improvement in control quality and control comfort
• Improvement in automatic brake intervention by the active/dynamic cruise control
ACC/DCC
• Improvement in the control accuracy of the HDC function
• Realization of additional brake functions
Wheel Speed Sensor
Active wheel speed sensors with an integrated evaluator circuit are used together with
the xDrive.
The active wheel speed sensors require a power supply for their operation. The output
signal is sent as a data protocol based on the pulse-width modulation method (PWM).
The PWM signal is used for the purpose of determining the road speed. The pulse width
contains additional information relating to the direction of rotation, standstill detection,
installation position detection, and air gap reserve to the sensor ring. (example : sends
one pulse every 0.75 s when the wheel is stationary)
The direction of rotation is determined by the internal signal offset of three correspond-
ingly arranged Hall-effect elements in the sensor.
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E61 Sports Wagon
Index Explanation
1
Sensor ring
2
Sensor-IC with Hall sensor
3 Sensor housing