3 Series E91 325xi (N52K) TOUR
Advantage: Shortest possible braking distances in emergency braking situations by achieving ABS regulation on
all four wheels.
The brake pedal is frequently not depressed strongly enough in emergency braking situations. ABS regulation is
then not activated.
In the following situations, the return pump increases the brake pressure until ABS regulation is activated:
-
When the brake pedal is rapidly depressed with insufficient pedal force
-
When the brake pedal is depressed slowly and the demand for deceleration is subsequently high, after one
wheel reaches the ABS control threshold.
Which wheel locks first depends on load and coefficient of friction of the road surface.
Example of a typical situation:
The traffic slows, making light braking necessary at first, but then demands as short a stopping distance as
possible.
Trailer stabilisation control
Trailer stabilising control detects when a trailer is rocking about its vertical axis. The system functions at a speed
of about 65 km/h when the trailer socket is in use.
With the aid of the DSC sensors, Dynamic Stability Control (DSC) monitors the vehicle's yaw behaviour.
If the trailer's rocking motion exceeds the limit, the engine output is reduced. In addition, DSC brakes all four
wheels automatically.
If DSC is deactivated or faulty, then the trailer stabilising control does not work either.
HDC: Hill Descent Control
Hill descent control (HDC) is an automatic cruise control system on all-wheel-drive vehicles for driving downhill.
HDC automatically reduces the vehicle's speed. The brakes are applied on all four wheels to reduce road speed
to just above walking pace. This allows stable downhill driving on steep and slippery surfaces.
HDC holds this speed constant (all DSC functions remain active).
The vehicle's road speed can be continuously varied within the specified values by depressing the accelerator
pedal and brake pedal or the cruise-control system steering-column stalk.
> E60, E61
HDC can be switched on and off at the Central Information Display (CID): "Settings" menu and "Vehicle settings"
submenu.
At the factory, HDC is assigned to the lower freely programmable button on the multi-function steering wheel.
> E83 and E90, E91, E92
HDC can be activated and deactivated via a separate button in the SZM (centre console switch cluster).
Electronically controlled deceleration
The electronically controlled deceleration (ECD) reacts to a demand from Active Cruise Control (ACC).
When the ACC system requires deceleration, DSC responds by applying the disc brakes on all four wheels
(maximum rate of retardation 2.5 m/s
2
).
When the car is on a decent with the speed preset by the driver, ECD automatically applies the brakes in order
to keep the car's speed constant at the preset value.
When the brakes are applied automatically in this way, the bake lights are activated in accordance with the
requirements of road-safety legislation.
SBT Dynamic Stability Control 8Plus E60, E61, E63, E64, E83, E90, E91, E92
BMW AG - TIS
12.02.2013 12:11
Issue status (12/2007) Valid only until next DVD is issued
Copyright
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