2002 BMW Z3 traction control

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IndexDataTechnologyRepairsMaintenanceControlsOverview
Dynamic Stability Control (DSC)*Switch off DSC/activate ADBPress the DSC switch (arrow) Ð the indi-
cator lamp comes on and remains on.
DSC has been switched off; ADB is in
ready mode.
In the following exceptional circum-
stances, it may be effective to activate
the ADB for a short period:
>When rocking the vehicle or starting
off in deep snow or on loose surfaces
>When driving on snow-covered
grades, in deep snow, or on a snow-
covered surface that has been
packed down from being driven on
>When driving with snow chains.367de739
Switch off DSC and ADBHold the DSC switch down for at least
3 seconds. The indicator lamp and the
red warning lamp for the brake
hydraulic system remain on.
In this case, no interventions to
increase stability and traction for engine
and brakes are carried out.
To maintain vehicle stability, drive
with the DSC switched on when-
ever possible.<
Reactivate DSC and ADBPress the button again; the indicator
lamp or the indicator lamps will go out.
The laws of physics cannot be
repealed, even with DSC. It will
always be the driver's responsibility to
drive in a manner that matches road
conditions. We therefore urge you to
avoid using the additional safety margin
of the system as an excuse for taking
risks.
The DSC is deactivated and will not
carry out any stabilizing intervention
when the ADB is in ready mode.
Do not make any modifications to the
DSC system. Allow only authorized
technicians to perform service proce-
dures on the DSC.<
You will find additional details
concerning DSC in the chapter
"Advanced technology" on page 165.

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To ensure that your vehicle provides
maximum economy throughout a long
service life, we request that you
observe the following:
Engine and differentialUp to 1,200 miles (2,000 km):
Drive with varying engine and road
speeds, but do not exceed 4,500 rpm
or 100 mph (150 km/h).
Comply with 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 later in the
course of the vehicle's service life.
TiresDue to technical factors associated with
their manufacture, tires do not achieve
their full traction potential until an initial
break-in period has elapsed. You should
therefore drive with extra caution during
the initial 200 miles (300 km).
Comply with 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 hydro-
planing, and can lead to partial or
complete loss of traction, vehicle
control and braking effectiveness.
Reduce your speed on wet roads.<
Brake systemApprox. 300 miles (500 km) must
elapse before the brake pads and
rotors achieve the optimal surface and
wear pattern.
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 light up
when the parking brake is applied.
Vacuum for the brake system booster
on your BMW is available only when the
engine is running. When you move the vehicle with the engine off Ð for instance
,
by towing Ð substantially higher levels
of pedal force will be required to brake
the vehicle.<
ClutchThe clutch will reach optimal function
after approx. 300 miles (500 km). Shift
gears carefully during the break-in
period.
Break-in procedure

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IndexDataTechnologyRepairsMaintenanceControlsOverview
Antilock Brake System (ABS)The conceptThe Antilock Brake System (ABS) keeps
the wheels from locking during braking,
thereby enhancing active driving safety.
The reason: locked wheels are
dangerous. When the front wheels
slide, the driver loses steering control
over the vehicle. Traction loss at the
rear wheels can cause the rear end to
break into an uncontrolled skid.
The system can achieve the shortest
braking distances possible under most
conditions (on straight-aways or in
curves, on the various road surfaces).
ABS is designed to meet two essential
requirements during every brake appli-
cation:
>To help provide vehicle stability
>Assured ability to steer and maneuver
on the various road surfaces (asphalt,
concrete, dirt, wet conditions, snow
and ice).
Braking with ABSThe system is operative once the
vehicle exceeds a speed of approx.
6 mph (10 km/h). It is inactive once
again below approx. 4 mph (6 km/h).
Therefore, the wheels could theoreti-
cally tend to lock in the final phase of a
braking action, but this is insignificant in
actual practice.
If you are in a situation which 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 avoid possible
obstacles with a minimum of steering
effort, despite the full brake application.The ABS closed-loop control circuit
cycles in fractions of a second. The
pulsation at the brake pedal, together
with sounds generated by the hydraulic
control system, indicate to you that the
vehicle is approaching its maximum
braking range. It is a reminder to you
that you must adapt the vehicle's road
speed to existing road conditions.
On road surfaces that have a loose
surface layer on a firm base with good
traction (on gravel, deep sand or snow,
for example), braking distances may be
longer than with locked wheels. This
also applies for driving with snow
chains. However, ABS continues to
provide enhanced vehicle stability and
steering response under these condi-
tions.

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IndexDataTechnologyRepairsMaintenanceControlsOverview
Winter operationThe onset of winter is often accompa-
nied by rapid changes in weather.
Adaptations in driving style should be
accompanied by preparations on the
vehicle itself to ensure that your vehicle
operation through the winter remains
safe and trouble-free.CoolantEnsure that the coolant contains the
year-round 50 : 50 ratio of water and
antifreeze with corrosion inhibitor. This
mixture provides protection against
freezing down to approx. Ð 34 7
(Ð 37 6). Replace the coolant every
three years.LocksBMW door lock deicer can be used to
free the doors if they are frozen. This
deicer also contains lubricant.
After using deicer, treatment with BMW
lock cylinder grease is recommended.
Rubber seals and components In order to prevent freezing, apply BMW
rubber treatment to weather-stripping
on the doors, hood, luggage compart-
ment and to convertible top seals.
A full range of car-care products is
available from your BMW center.< Snow chainsBMW snow chains
* can be mounted on
both summer and winter tires. Mount
them in pairs on the rear wheels only.
Comply with the manufacturer's safety
precautions. Do not exceed a speed
limit of 30 mph (50 km/h) when driving
with chains. As an exception in this
situation, we recommend that you
switch off the ASC+T/DSC
* system
when snow chains are mounted. Refer
to pages 73, 74.
Starting offWhen starting from a full stop or
"rocking" free in deep snow, we recom-
mend that you switch off the ASC+T/
DSC
* system, refer to pages 73, 74.
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. Shift down
into the next lowest gear when
approaching uphill or downhill grades.
Maintain an adequate distance between
yourself and the vehicle ahead.Brakes Winter road conditions substantially
reduce the traction available between
the tires and the road surface.
Remember that Ð in every situation Ð
braking distances will be significantly
longer as a result of this.
ABS is intended to prevent the wheels
from locking during brake applications,
thus helping to maintain vehicle stability
and steering response.

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Winter operation Power steeringIf it should occur that the ABS does not
respond in a critical braking situation
and the wheels lock: reduce the pres-
sure on the brake pedal until the wheels
just start to roll again while still main-
taining enough force to continue
braking. Following that, increase pedal
pressure again. Reduce the pressure as
the wheels lock, then reapply pressure.
Repeat this process.
This type of staggered braking will
shorten the braking distance, and the
vehicle still remains responsive to
steering.
You can still attempt to steer around
hazards once you have reduced the
pressure on the brake pedal.
Do not shift down on slick road
surfaces. Doing so could cause
the rear wheels to lose traction and
skid, which could result in the loss of
vehicle control.<
Declutch during hard braking on
road surfaces which provide only
poor or uneven traction.<
Skid controlDepress 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
linings 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 light
up when the parking brake is
applied.<
If you notice a change in steering
response (high steering effort, for
example):
Consult a BMW center to have the
system checked.
If the power steering fails,
increased effort will be required
to steer the vehicle.<

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IndexDataTechnologyRepairsMaintenanceControlsOverview
Tire condition Tire replacementmoderate speeds and with only small
amounts of water on the road.
Never continue driving 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 causes over-
heating and 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 damage (up to and including
sudden and complete air loss) can pose
an extreme hazard for both vehicle
occupants and other road users.< To maintain good handling and vehicle
response, use only tires of a single tread
configuration from a single manufac-
turer. BMW tests and approves wheel
and tire combinations, refer to page 116.
DOT Quality GradesTread wear
Traction AA A B C
Temperature A B C
All passenger vehicle tires must
conform to Federal Safety
Requirements in addition to these
grades. 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.

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Tire replacementTractionThe 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 vehicle tires must meet
under the Federal Motor Vehicle Safety
Standard No. 109. Grades B and A
represent 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 GradingQuality 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 as this
could negatively affect driving
safety. This is due to the possible varia-
tions in casing structures and, in some
cases, to their extreme age, factors
which can lead to a decrease in their
durability.<

Overview
Controls and features
Operation, maintenance
Owner service procedures
Technical data
Index Advanced technology
163n
IndexDataTechnologyRepairsMaintenanceControlsOverview
Adaptive Transmission Control
(ATC)164
Airbags164
Automatic Stability Control plus
Traction (ASC+T)/Dynamic
Stability Control (DSC)165
Car radio reception166
Safety belt tensioner166
Technology