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Dynamic Stability Control (DSC) Ð BMW 325xiThe conceptDSC maintains vehicle stability, even in
critical driving situations.
The system optimizes vehicle stability
during acceleration and when starting
from a full stop, as well as optimizing
traction. In addition, it recognizes
unstable vehicle conditions, such as
under- or oversteering, and, as far as is
possible within the laws of physics,
helps keeping the vehicle on a steady
course by reducing the engine speed
and brake applications to the individual
wheels.
DSC is operational every time you start
the engine. DSC includes the functions
of ADB-X and CBC.
The Automatic Differential Brake
(ADB-X) enhances traction in critical
situations (such as those encountered
on snow-covered roads) by using
selective braking intervention to replace
the limited-slip functions executed by
the differential and transfer case in
conventional drivetrains.
Indicator lamp
The indicator lamp in the instru-
ment cluster will go out shortly
after the ignition has been
switched on, refer to pages 18, 19.
The indicator lamp flashes:
DSC controls the drive and braking
forces.
The indicator lamp stays lit:
DSC has been switched off via the
button; ADB-X is operational.
ADB-X control intervention is not indi-
cated.
If the indicator lamp fails to go out
when you press the DSC button,
this indicates a malfunction in the DSC
and ADB-X systems; the stability
enhancement functions described on
the left are no longer available.<
The vehicle will remain completely
operational, however, without DSC. In
the event of a malfunction, please
consult your BMW center, refer to
pages 18, 19.
To deactivate DSCPress the DSC button briefly, the indi-
cator lamp comes on and remains lit.
DSC is switched off, and ADB-X reverts
to its maximum torque-transfer mode.
In the following exceptional circum-
stances, it may be effective to deacti-
vate the DSC for a short period:
>When rocking the vehicle or starting
off in deep snow or on loose surfaces
>When driving with snow chains.
To maintain vehicle stability,
always drive with the DSC
switched on whenever possible.<
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Hill Descent Control (HDC) Ð BMW 325xiThe conceptBy reducing the vehicle's speed on
steep downhill stretches, HDC main-
tains predictable vehicle handling
response to provide you with control of
your BMW during extreme descents.
The vehicle slows to a pace just slightly
faster than walking speed.
HDC is available for activation at
vehicle speeds below approx. 22 mph
(35 km/h). When driving down steep
hills, the vehicle reduces speed auto-
matically down to slightly more than
double walking speed (approx. 8 mph/
12 km/h) and then maintains this speed
at a constant.
You can use the accelerator or brakes
to vary this automatically controlled
speed within a range extending from
approx. 3 mph (5 km/h) to 15 mph
(25 km/h).
In conjunction with the multifunction
steering wheel, you can use the
+/Ð button to set the cruise control to a
target speed in the range from approx.
3 mph (5 km/h) to 15 mph (25 km/h).
HDC is automatically deactivated once
vehicle speed again exceeds approx.
35 mph (60 km/h).
To activate the systemPress the HDC button; the green indi-
cator lamp integrated within the button
comes on.
The indicator lamp flashes whenever
the system is actively intervening to
control your speed with automatic
brake applications.To deactivate the systemPress the button again, the indicator
lamp goes out.
HDC is automatically deactivated once
the vehicle accelerates to more than
35 mph (60 km/h) as well as whenever
you switch off the ignition.
To use HDCWith manual transmission:
You should always ensure that either
reverse or first gear is engaged before
using HDC, as the engine's braking
effect is most pronounced in these
gears, and only reduced engine braking
is available in higher gears.
With automatic transmission:
HDC is available for use in all ranges.System malfunctionsSignalled by the indicator lamp, which
responds to problems by going out
while HDC is in operation or by failing
to come on when you activate the
system:
HDC is temporarily not available if
brake temperature is too high.
If the DSC indicator lamp comes
on at the same time:
There is a fault in the HDC and
DSC systems. Have your BMW center
inspect this system as soon as
possible.
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Tire Pressure Monitor (RDC)
*
The conceptRDC monitors the tire pressures at all
four wheels while the vehicle is moving.
The system provides an alert whenever
the inflation pressure drops significantly
below the specified pressure in one or
more tires.
In order for the system to learn the
correct tire inflation pressure, check the
inflation pressure in all tires according
to the inflation pressure table on
page 25 and make corrections as
necessary. Then activate the system.
This indicator lamp in the instru-
ment cluster will inform you if
the tire pressure is not correct.
To activate the system1. Turn ignition key to position 2 (do not
start the engine)
2. Press the button long enough for the
yellow indicator lamp in the instru-
ment cluster to light up for a few
seconds
3. After a few minutes driving time, the
RDC adopts the current pressure
levels as the reference, and from that
point on, can detect and report a flat
tire.
You will only have to repeat this proce-
dure following a correction of the tire
inflation pressure. Otherwise, RDC
functions automatically when the igni-
tion key is in position 2, and thus oper-
ates whenever the vehicle is driven.
In the event of loss in inflation
pressureIf the inflation pressure has dropped
significantly over a long period of time
(which is normal for any tire), the yellow
indicator lamp will come on.
This alerts you to have the tires inflated
to the specified pressures as soon as
possible.
If you are prompted to check the
tire pressure shortly after a
correction has been made, this indi-
cates that the corrected values were
not accurate. Please check the inflation
pressure again and make corrections
according to the inflation pressure
table. Then activate the system once
again.<
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Tire Pressure Monitor (RDC)
*
In the event of a flat tireIf there is a tire failure with loss of pres-
sure, the indicator lamp comes on with
a red lamp. In addition, an acoustic
signal is sounded.
If this occurs, reduce vehicle speed
immediately and stop the vehicle in a
safe location. Avoid hard brake applica-
tions. Do not oversteer. Replace the
wheel and flat tire.
The space-saver spare tire is
provided for temporary use only in
the case of a tire failure. It does not
have RDC electronics and is not moni-
tored. The spare tire
that has the same
dimensions as the tires already
mounted on the vehicle is equipped
with the necessary RDC electronics
and will be also monitored once the
tires have been mounted and the
system activated.<
RDC cannot alert you to severe
and sudden tire damage caused
by external factors.<
Have the tires changed by your
BMW center.
Your BMW center has the information
needed for working with RDC and is
equipped with the necessary special
tools.<
System interferenceLocal devices using the same radio
frequency can interfere with RDC.
The yellow indicator lamp will come on
during the malfunction.
The indicator lamp also comes on
>in the event of a system fault
>if a wheel is mounted without the
appropriate electronics
>if, in addition to the spare tire, addi-
tional wheels with RDC electronics
are on board.
Please contact your BMW center for
additional information.
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Flat Tire Monitor
*
The conceptAs you drive, the Flat Tire Monitor
keeps track of pressure levels in all four
tires in order to detect and warn of any
substantial pressure loss.
The system actually detects pressure
loss by monitoring differences in the
relative speeds of the four wheels. It
interprets variations outside specified
limits as severe pressure loss, and then
responds by generating a warning.
To initialize the systemInitializing is necessary to familiarize the
system with the correct inflation pres-
sure.
Repeat this process after any changes
in tire inflation pressure, tire rotation or
replacement. Do not carry out further
system initialization after adjusting the
inflation pressure and letting the system
"learn" the correct pressures.
1. Check the tire inflation pressure in all
the tires, comparing them with the
inflation pressure table on page 25,
and correct their pressure if neces-
sary
2. Turn the ignition key to position 2
3. Press button as long as you need to
until the indicator lamp in the instru-
ment cluster lights up. After a little
while, the indicator lamp will go out
by itself
4. After a few minutes driving time, the
Flat Tire Monitor adopts the current
pressure levels as the reference, and
from that point on, can detect and
report a flat tire.
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Flat Tire Monitor
*
Activate/deactivate the systemThe Flat Tire Monitor automatically
assumes operation whenever you turn
the ignition key to position 2. Unless
manually deactivated, it is always on
during normal vehicle operation.
To deactivate the system: press the
button, the yellow indicator lamp comes
on.
To activate the system: press the
button again, the indicator lamp goes
out.
You should deactivate the system
before driving with snow chains, as the
chains can generate spurious warnings
and/or prevent the system from
detecting actual pressure loss.
In the event of a flat tire
The red warning lamp in the
instrument cluster lights up to
warn of pressure loss and tire
failure. This visual alert is accompanied
by an acoustic warning signal. Reduce
your speed immediately, and steer and
brake gently as you bring the vehicle to
a stop.
To reset the warning lamp: after
replacing the flat tire you will need to
reset the red warning lamp manually:
maintain pressure on the Flat Tire
Monitor button until the warning lamp
goes out. Then reinitialize the system.
The Flat Tire Monitor cannot
provide you with advance warning
of sudden and severe tire damage
caused by external factors.
The system also does not detect the
gradual and minor loss of pressure that
all tires display over extended periods
of time.<
Check the tire inflation pressures
on a regular basis, correcting
them as necessary, refer to page 24.
The system may respond to operation
on slippery or snow-covered road
surfaces with false warnings or delays
in detecting actual pressure loss.
Performance-oriented driving (slip at
the drive wheels, high rates of lateral
acceleration) can also increase the time
that the Flat Tire Monitor requires to
detect a flat tire.<
System malfunctionsThe yellow indicator lamp in the instru-
ment cluster lights up and remains on
until the problem is corrected.
Please refer the problem to your BMW
center.
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Driving notes Antilock Brake System
Brakes: do not drive with your foot
resting on the brake pedal. Even
light but consistent pressure on the
brake pedal can lead to high tempera-
tures, accelerated brake wear and
possibly even brake failure.
Aquaplaning: when driving on wet or
slushy roads, reduce your speed. If you
do not, a wedge of water may form
between tires and road surface. This
phenomenon can lead to partial or
complete loss of contact between the
tires and road surface, vehicle control
and braking ability.
Driving through water: do not drive
through water on the road if it is deeper
than 1 ft (30 cm), and then only at
walking speed. Otherwise, the vehicle's
engine, the electrical systems and the
transmission may be damaged.
Cargo area cover: never use it to store
heavy or hard objects, as otherwise
occupants could be injured during
braking maneuvers.
Clothes hooks: when hanging clothing
from the hooks, be sure that they will
not obstruct the driver's vision. Do not
hang heavy objects on the hooks. If you
do so, they could cause personal injury
during braking or evasive maneuvers.<
The conceptThe Antilock Brake System (ABS) keeps
the wheels from locking during braking,
thereby enhancing active driving safety.Braking with ABSIf you are in a situation that requires full
braking, you will exploit the full benefits
of the ABS system if you apply
maximum pedal pressure ("panic stop").
Since the vehicle maintains steering
responsiveness, you can avoid possible
obstacles with a minimum of steering
effort, despite the full brake application.
Pulsation at the brake pedal combined
with sounds from the hydraulic circuits
indicates to the driver that ABS is in its
active mode.
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Information for your safetyThe factory-approved radial tires are
matched to the vehicle and have been
selected to provide optimum safety and
driving comfort.
It is not merely the tire's service life, but
also driving comfort and Ð above all else
Ð driving safety that depend on the
condition of the tires and the mainte-
nance of the specified tire inflation
pressure.
Incorrect tire inflation pressure is
a frequent cause of tire damage. It
also significantly influences the road-
holding ability of your BMW. Be sure to
check the tire inflation pressure,
including the space-saver spare tire or
the spare tire, on a regular basis, at
least twice a month and before every
extended journey, refer to page 24. If
this is not done, incorrect tire pressures
can cause driving instability and tire
damage, ultimately resulting in an
accident.<
Tire tread Ð tire damageInspect your tires frequently for tread
wear, signs of damage and for foreign
objects lodged in the tread. Check the
tread depth.
Tread depth should not be allowed to
go below 0.12 in (3 mm), even though
the legally specified minimum tread
depth is 0.063 in (1.6 mm). Tread wear
indicators (arrow) are embedded in the
base of the tire's tread. Their locations
are indicated by the legend TWI Ð Tread
Wear Indicator Ð at various points on
the tire's shoulder. When the tread
reaches a depth of 0.063 in (1.6 mm),
these indicators appear to signal that
the tires have worn to the minimum
legal level. Below 0.12 in (3 mm) tread
depth, there is an increased risk of
aquaplaning, even at relatively
moderate speeds and with only small
amounts of water on the road.
Do not drive on a deflated (flat)
tire. A flat tire greatly impairs
steering and braking response, and can
lead to complete loss of control over
the vehicle.
Avoid overloading the vehicle so that
the permitted load on the tires is not
exceeded. Overloading leads to over-
heating and causes damage inside the
tires. The ultimate result can assume
the form of a sudden air loss.
Unusual vibrations encountered during
normal vehicle operation can indicate a
flat tire or some other vehicle malfunc-
tion. The type of problem can be
caused by contact with curbs, etc. This
is also true for irregularities in the
vehicle's handling characteristics, such
as a pronounced tendency to pull to the
left or right. Should this occur, respond
by immediately reducing your speed.
Proceed carefully to the nearest BMW
center or professional tire center, or
have the vehicle towed in to have it, its
wheels and tires inspected.
Tire inflation pressure
Tire condition