BMW 2012 3 Series M3 Сoupe - Manual (Page 106)

105
Technology for driving comfort and safety Controls
tire to overheat and can lead to tire failure.
Underinflation also reduces fuel efficiency and
tire tread life, and may affect the vehicle’s han-
dling and stopping ability. Please note that the
TPMS is not a substitute for proper tire mainte-
nance, and it is the driver’s responsibility to
maintain correct tire pressure, even if underin-
flation has not reached the level at which the
TPMS low tire pressure telltale illuminates.
The TPMS malfunction indicator is combined
with the low tire pressure telltale. When the sys-
tem detects a malfunction, the telltale will flash
for approximately one minute and then remain
continuously lit. This sequence will continue
upon subsequent vehicle startups as long as
the malfunction exists. When the malfunction
indicator is illuminated, the system may not be
able to detect or signal low tire pressure as
intended. TPMS malfunctions may occur for a
variety of reasons, including the installation of
replacement or alternate tires or wheels on the
vehicle that prevent the TPMS from functioning
properly. Always check the TPMS malfunction
telltale after replacing one or more tires or
wheels on your vehicle to ensure that the
replacement or alternate tires and wheels allow
the TPMS to continue to function properly.
Active steering
The concept
Active steering varies the turning angle of the
front wheels in relation to steering wheel move-
ments. It also varies the steering force required
to turn the wheels depending on the speed at
which you are driving.
When you are driving in the low speed range,
e.g. in a town or when parking, the steering
angle is increased, i.e. steering becomes very
direct and less effort is required to turn the
wheels. In the higher speed range, on the other
hand, the steering angle is reduced as the
speed increases. This improves the handling of
your BMW over the entire speed range.
In critical situations, the system can make tar-
geted corrections to the steering angle pro-
vided by the driver and thus stabilize the vehicle
before the driver intervenes. This stabilizing
intervention is simultaneously deactivated
when DSC is switched off, refer to page
98 .
Malfunction
The warning lamps light up and a
message is displayed on the Control
Display. Active steering is malfunc-
tioning or is temporarily deactivated.
At low speeds, greater steering wheel move-
ments are required, whereas at higher speeds
the vehicle reacts more sensitively to steering
wheel movements. The stability-enhancing
feature may also be deactivated. Drive cau-
tiously and think well ahead.
Deactivation
Active steering is deactivated to perform an ini-
tialization. A message indicates that the feature
is deactivated. Initialization may take several
minutes.
If the message does not disappear during the
current trip, have the system checked.
Defect
If there is a defect, a corresponding text mes-
sage appears. Have the system checked.
Servotronic
The concept
The Servotronic varies the steering force
required to turn the wheels relative to the vehi-
cle speed.
At low speeds, the steering force is strongly
assisted, i.e. less force is needed for steering.
As the vehicle speed increases, the steering
assisting power is reduced.
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