X Series E53 X5 4.8is (N62-S) OFFRD
DSC OK, VTG control unit defective
-> All-wheel drive in emergency mode
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DSC/xDrive telltale and warning lights, ABS telltale and warning lights and general brake warning lamp light
up and acoustic signal:
Total failure of the DSC and/or malfunction of the VTG control unit
-> All-wheel drive in emergency mode
> E53, E83
The instrument cluster is the data interface (= gateway) between the K-bus and the PT-CAN.
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JBE: Junction box electronics
> E70
The JBE is the data interface (= gateway) between the K-CAN and PT-CAN.
The junction box comprises the JBE and the power distributor.
System functions
xDrive comprises the following functions:
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Control of the locking torque for the multi-plate clutch
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Emergency operation
Control of the locking torque for the multi-plate clutch
The locking torque for the multi-plate clutch in the transfer case can be regulated. This means that the front axle
can be smoothly coupled to the drive train. The drive torque at the front axle can be increased or reduced in
response to the road situation and conditions.
The DSC control unit calculates the locking torque for the multi-plate clutch as follows:
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Pre-activation = driver's command
•
Driving dynamic control
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Detection of different tyre rolling circumferences
Pre-activation
The pre-activation circuit reflects the driver's wishes. In other words. the pre-activation circuit is used to
calculate the necessary locking torque.
The evaluation criteria below are taken into account to in determining the driver's command:
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Accelerator-pedal value
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Engine torque
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Engine speed
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Vehicle road speed
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Gear engaged
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Steering angle
Driving dynamic control
Driving dynamic control monitors the slip on the front and rear axles. Driving dynamic control has the task of
achieving optimum traction and keeping the car stable or to stabilise it.
The following evaluation criteria are taken into account by the monitoring system:
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Wheel speeds
SBT xDrive E53, E70, E83
BMW AG - TIS
12.02.2013 22:15
Issue status (12/2007) Valid only until next DVD is issued
Copyright
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