Asc+t/dsc – BMW 01 41 0 155 307 User Manual

Page 173

173

Index

Data

Technology

Repairs

Car care

Controls

Overview

On vehicles with an automatic trans-
mission, the Adaptive Transmission
Control (ATC) uses a number of factors
to calculate the gear which provides
maximum efficiency. In this process, it
considers your individual driving style
as well as current driving conditions.

ATC recognizes your personal driving
style from the positions and movements
of the accelerator pedal, deceleration
when braking, and lateral acceleration
through curves. Based on different shift
characteristics – from comfort-oriented
to performance-oriented – ATC will
select the appropriate gear.

463us005

In order to include driving conditions in
its calculations, ATC registers curves
and both uphill and downhill gradients.
For example, if you maintain speed
through a curve, the transmission does
not shift up. On uphill gradients, it shifts
up only when the engine speed
increases in order to make more effi-
cient use of power reserves. On down-
hill gradients, ATC shifts down when
the speed of the vehicle increases and
the driver must apply the brakes.

Highly sensitive sensors monitor the
number of revolutions of the wheels,
steering angle, lateral acceleration,
brake pressure and the movement of
the vehicle around its vertical axis.

If differences in the wheel speeds
occur, ASC+T recognizes the danger of
wheelspin and reduces torque. If
necessary, the system also responds
with additional brake applications at the
rear wheels.

In addition, DSC permanently monitors
the vehicle's current operating condition
and compares it with an ideal condition
that is calculated from the sensor's
signals. If deviations from this occur
(understeering or oversteering, for
instance), DSC can stabilize the vehicle
in fractions of a second by reducing
engine output and with the assistance of
braking intervention at individual
wheels. As a result, dangerous skids can
be prevented even as they are just
beginning.

You may need some time to become
accustomed to this system's interven-
tion. However, it provides optimum drive
force and vehicle stability.

The braking intervention may be
accompanied by sounds specific to the
system.

ATC

ASC+T/DSC