2001 BMW 330i TOURING traction control

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IndexDataTechnologyRepairsCar careControlsOverview
DSC Ð BMW 325xiThe conceptDSC maintains vehicle stability, even in
critical driving situations.
The system enhances vehicle stability
during acceleration and when starting
up from a full stop, and optimizes trac-
tion as well. In addition, it recognizes
unstable vehicle conditions, such as
understeering or oversteering, and, as
far as is possible within the laws of
physics, helps keep the vehicle on a
steady course by reducing the engine
output and brake applications to the
individual wheels.
The DSC is operational every time you
start the engine. DSC contains ADB-X
und DBC, refer to page 118.
The ADB-X (Automatic Differential
Braking) replaces the function of
conventional differential and transverse
lock through brake intervention, and
increases traction whenever conditions
merit, e. g. when driving on snow-
covered streets.Indicator lamp
The indicator lamp on the instru-
ment cluster will go out shortly
after the ignition has been
started. Refer to pages 21, 22.
If the indicator lamp flashes:
DSC controls the drive and braking
forces.
The indicator lamp stays lit:
DSC is switched off via the switch;
ADB-X is operational.
ADB-X intervention not indicated.
If the indicator lamp does not go
out after repeatedly pressing the
DSC switch, then the DSC and the
ADB-X are defective, and the interven-
tion described to the right is then no
longer available.<
The vehicle will remain completely
operational, however, without DSC. In
the event of a fault, please see your
BMW center. Refer to pages 21, 22.
Deactivate the DSCPress the DSC button; the indicator
lamp comes on and stays on.
The DSC has been switched off and the
ADB-X is designed for maximum
output.
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. Refer
also to page 121.
To maintain vehicle stability,
always drive with the DSC on
whenever possible.<460de313

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To ensure maximum economy and a
long service life, we request that you
observe the following suggestions.
Engine and differentialUp to 1,200 miles (2,000 km):
Drive at varying engine speeds and road
speeds, but do not exceed the following
engine or road speeds during this time:
4,500 rpm or 100 mph (160 km/h).
Obey your local and state maximum
speed limits.
Refrain from using full throttle and avoid
pressing the accelerator beyond the
"kickdown" point.
After you have driven 1,200 miles
(2,000 km), you can gradually increase
the engine and road speeds.
You should also comply with these
break-in procedures if the engine or
differential is replaced at a later point.
TiresDue to technical factors associated
with their manufacture, tires do not
achieve their full traction potential until
an initial break-in period has elapsed.
Thus drive with extra care during the
initial 200 miles (300 km).
Obey your local and state maximum
speed limits.
When the vehicle is operated on
wet or slushy roads, a wedge of
water may form between the tire and
the road surface. This phenomenon is
referred to as aquaplaning, or hydropla-
ning, and can lead to partial or
complete loss of traction, vehicle
control and braking effectiveness.
Reduce your speed on wet roads.<
Brake systemAfter approximately 300 miles (500 km),
the brake pads and discs achieve the
optimal pad surface and wear patterns
required for trouble-free operation and
long service life.
To break in the separate parking brake
drums, apply the parking brake lightly
when coasting to a standstill (at a traffic
signal, for instance), provided that
traffic conditions allow you to do so.
To avoid corrosion, repeat this proce-
dure from time to time.
The brake lamps do not come on
when the parking brake is applied.
Vacuum for the brake system servo unit
on your BMW is available only when the
engine is running. When you move the
vehicle with the engine off Ð when
towing, for example Ð substantially
higher levels of pedal force will be
required to brake the vehicle. optimally after about 300 miles
(500 km). Engage the gears carefully
during the break-in period.
Break-in procedures

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Catalytic converter Antilock Brake System (ABS)
Be sure to observe the instruc-
tions above to prevent unburned
fuel from reaching the catalytic
converter, otherwise, the catalytic
converter could overheat and be
damaged.
High temperatures occur in any vehicle
equipped with a catalytic converter.
Heat shields are installed adjacent to
some sections of the exhaust system.
Never remove these shields; do not
apply undercoating to their surfaces.
When driving, standing at idle, and
parking the vehicle, take care to avoid
contact between the exhaust system
and flammable materials (grass, hay,
leaves etc.). Such contact could lead to
a fire, resulting in personal injury and
property damage.<
The concept ABS enhances active driving safety by
helping to prevent the wheels from
locking under braking. The reason:
locked wheels are dangerous. When the
front wheels slide, the driver loses
steering control over the vehicle. Trac-
tion loss at the rear wheels can cause
the rear end to break into an uncon-
trolled skid.
The system can achieve the shortest
braking distances possible under most
conditions (on straight-aways and in
curves, on asphalt, ice, wet road
surfaces, etc.).
ABS is designed to meet two essential
requirements during every brake appli-
cation:
>To help provide vehicle stability.
>Assured ability to steer and
maneuver Ð on the various road
surfaces (asphalt, concrete, dirt,
wet conditions, snow, ice).
The system can achieve the shortest
braking distances possible under most
conditions (on straight-away and in
curves, on asphalt, ice, wet road
surfaces, etc.).
Braking with ABSThe system is operative once the
vehicle exceeds a speed of approx.
6 mph (10 km/h). It is deactivated once
again below approx. 4 mph (6 km/h).
This means that the wheels can lock in
the final phase of a panic stop Ð a factor
of no significance in actual use.
If you are in a situation that requires full
braking, you will exploit the full benefits
of the ABS system if you apply
maximum brake pressure ("panic
stop"). Since the vehicle maintains
steering responsiveness, you can
nevertheless avoid possible obstacles
with a minimum of steering effort.
The ABS closed-loop control circuit
cycles in fractions of a second. A pulsa-
tion at the brake pedal, together with
the sounds associated with the
hydraulic controls, tells you that the
brake system is within its maximum
limit range, and reminds you that you
should adapt road speed to the road
conditions.
On road surfaces that have a loose
surface layer on a firm base with good
traction (on gravel or snow, for
example), or when snow chains are
mounted, braking distances may be
longer than with locked wheels.

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IndexDataTechnologyRepairsCar careControlsOverview
Winter operationWinter is often accompanied by rapid
changes in weather. Adaptions in
driving style should be accompanied by
preparations on the vehicle itself to
ensure that your vehicle operates safely
and trouble-free throughout the winter
months.CoolantBe sure that the coolant mixture
contains the year-round ratio of 50:50
water and antifreeze/corrosion protec-
tion. This mixture will resist freezing to
approx. Ð34 7 (Ð37 6). Replace the
coolant every four years.LocksBMW door lock deicer can be used to
free them if frozen. This deicer also
contains lubricant.
After using the deicer, treatment with
BMW lock cylinder grease is recom-
mended.
Rubber seals and components To prevent the weather stripping from
freezing, apply a spray-on rubber treat-
ment or silicone spray to the door, hood
and tailgate seals.
A full range of car care products is
available from your BMW center. *
BMW snow chains can be mounted on
both summer and winter tires. Mount
them in pairs on the rear wheels only
and comply with the manufacturer's
safety precautions. Do not exceed a
maximum speed of 30 mph (50 km/h).
In this type of exceptional situation
where the snow chains are mounted,
deactivate the ASC+T/DSC. Refer to
page 79.
BMW 325xi: in a worst-case scenario,
i.e. if your vehicle is stuck on one side
or you cannot access one tire, then only
one chain may be attached to a rear
wheel for a short period of time.
Starting offWhen starting off from a full stop in
deep snow or when "rocking" the
vehicle to free it, it may be effective to
deactivate the ASC+T/DSC system for
a short period. Refer to page 79.Driving on low-traction road
surfacesUse smooth, gentle pressure to control
the accelerator pedal. Avoid excessive
engine speeds and shift to the next
higher gear at an early point. Downshift
into the next lower gear on ascents or
descents. Maintain an adequate
distance between yourself and the
vehicle ahead.

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Winter operationBrakingWinter road conditions substantially
reduce the amount of traction available
between the tires and the road surface.
Keep this in mind, because the braking
distance increases substantially.
ABS is intended to prevent the wheels
from locking during brake applications,
thus helping to maintain vehicle stability
and steering response.
If the ABS does not respond in a critical
braking situation and the wheels lock:
reduce the pressure on the brake pedal
until the wheels just start to roll again
while still maintaining enough force to
continue braking.
Then increase the pressure, reduce the
pressure when the wheels lock, reapply
pressure etc.
This staggered braking procedure will
reduce braking distances while helping
you maintain steering control.
You can then attempt to steer around
hazards after you have reduced pres-
sure on the brake pedal.Do not shift down on slick road
surfaces Ð if you want to decel-
erate. Doing so could cause the rear
wheels to lose traction and skid, which
could result in the loss of vehicle
control.<
Depress the clutch during hard
braking on road surfaces that
provide only poor or uneven traction.<
Skid control Depress the clutch and release the
accelerator pedal, or place the selector
lever of the automatic transmission into
the "Neutral" position. Countersteer
carefully and attempt to regain control
of the vehicle.
ParkingEngage 1st or reverse gear. If your
vehicle is equipped with an automatic
transmission, place the selector lever in
"Park." On vehicles with manual trans-
mission, also apply the parking brake
when parking on inclined surfaces. In
order to prevent the parking brake pads
from locking due to frost or corrosion,
dry them by gently applying the parking
brake as the vehicle is coming to a
stop. Make sure that following traffic
is not endangered.
The brake lamps do not come
on when the parking brake is
applied.<

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IndexDataTechnologyRepairsCar careControlsOverview
To maintain good handling and vehicle
response, use only tires of a single
tread configuration from a single manu-
facturer. BMW tests and approves
wheel/tire combinations. Refer to
page 129.DOT Quality GradesTreadwear
Traction AA A B C
Temperature A B C
All passenger car tires must
conform to Federal Safety
Requirements in addition to these
grades.< Tread wearThe tread wear grade is a comparative
rating based on the wear rate of the tire
when tested under controlled condi-
tions on a specified government test
course.
For example, a tire graded 150 would
wear one and one-half (1g) times as
well on the government course as a tire
graded 100. The relative performance
of tires depends upon the actual condi-
tions of their use, however, and may
depart significantly from the norm due
to variations in driving habits, service
practices and differences in road char-
acteristics and climate.
TractionThe traction grades, from highest to
lowest, are AA, A, B, and C.
Those grades represent the tire's ability
to stop on wet pavement as measured
under controlled conditions on speci-
fied government test surfaces of asphalt
and concrete. A tire marked C may have
poor traction performance.
The traction grade assigned to
this tire is based on straight-
ahead braking traction tests, and does
not include acceleration, cornering,
hydroplaning, or peak traction charac-
teristics.< TemperatureThe temperature grades are A (the
highest), B, and C, representing the
tire's resistance to the generation of
heat and its ability to dissipate heat
when tested under controlled condi-
tions on a specified indoor laboratory
test wheel.
Sustained high temperature can cause
the material of the tire to degenerate
and reduce tire life, and excessive
temperature can lead to sudden tire
failure. The grade C corresponds to a
level of performance which all
passenger car tires must meet under
the Federal Motor Vehicle Safety Stan-
dard No. 109. Grades B and A repre-
sent higher levels of performance on
the laboratory test wheel than the
minimum required by law.
The temperature grade for this tire
is established for a tire that is
properly inflated and not overloaded.
Excessive speed, under-inflation, or
excessive loading, either separately or
in combination, can cause heat buildup
and possible tire failure.< Uniform Tire Quality Grading Quality grades can be found where
applicable on the tire sidewall between
tread shoulder and maximum section
width. For example:
Tread wear 200 Traction AA
Temperature A
Do not use retreaded tires. Driving
safety may be impaired by their
use. This is due to the possible varia-
tions in casing structures and, in some
cases, to their extreme age, which can
lead to a decrease in their durability.<
Tire replacement

Overview
Controls and features
Operation, care
and maintenance
Owner service procedures
Technical data
Index Advanced technology
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IndexDataTechnologyRepairsCar careControlsOverview
Advanced technology:
Airbags172
Adaptive Transmission Control
(ATC)173
Automatic Stability Control plus
Traction ASC+T/Dynamic
Stability Control DSC173
Radio reception174
Four-wheel drive175
Safety belt tensioner175
Interior rearview mirror with
automatic dimmer176
Rain sensor177
Tire Pressure Control (RDC)178
Self-diagnostics179
Xenon lamps180
Technol-

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IndexDataTechnologyRepairsCar careControlsOverview
Four-wheel drive Safety belt tensionerThe transmission of power to the four
drive wheels is provided permanently
through a transfer box. The distribution
of torque between the front and rear
axles is 38% to 62%.
Traditional differential locks at the front
and rear axles and in the transfer box
are not required. Their function is
assumed by automatic braking inter-
vention at all four wheels. These trac-
tion interventions are governed by
Automatic Differential Brake (ADB-X), a
sub-function of DSC.
If a wheel tends to slip, it is braked
automatically by ADB-X until it once
again gains traction, and drive force
can be transmitted to that wheel. In
addition, the drive force is distributed to
the remaining wheels during this 530us133
system intervention. Engine output is
also reduced if necessary.
When the DSC is deactivated, the
ADB-X traction intervention is set for
the maximum drive force. However, the
engine intervention and the stability
controls are no longer available. For
this reason, DSC should only be deacti-
vated in the exceptional circumstances
described on page 81.
The BMW 325xi is not an off-road
vehicle. Instead, permanent four-wheel
drive provides a high degree of vehicle
stability and tractive ability under all
road conditions, and will aid you in crit-
ical driving situations, e. g. driving in
extreme winter conditions or on loose
road surfaces.The safety belt tensioner responds to
severe frontal collisions by tightening
the belts to ensure that occupants
remain firmly positioned in their seats.
A gas-pressure system retracts the
buckle assembly to tension the
shoulder and lap belts within fractions
of a second. This reduces the tendency
to slide under the lap belt.
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