wheel BMW Z3 2002 User Guide

Overview
Controls and features
Operation, maintenance
Owner service procedures
Technical data
Index Advanced technology
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IndexDataTechnologyRepairsMaintenanceControlsOverview
Special operating instructions:
Break-in procedure98
Driving notes99
Catalytic converter100
Antilock Brake System
(ABS)101
Disc brakes103
Brake system104
Winter operation105
Power steering106
Cellular phone107
Car radio reception107
Hardtop Ð roadster108
Wheels and tires:
Notes on inflation pressures110
Tire condition110
Tire replacement111
Tire rotation113
Wheel and tire
combinations114
Special features of winter
tires115
Snow chains115
Approved wheel and tire
specifications116In the engine compartment:
Hood118
Engine compartment120
Fluids for the washer
systems122
Washer nozzles122
Engine oil123
Coolant125
Brake fluid126
Vehicle Identification127
Care and maintenance:
The BMW Maintenance
System128
Airbags130
Storing your vehicle130
Laws and regulations:
Technical modifications132
California Proposition
65 Warning132
OBD interface socket133
Maintenance

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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
ABS Disc brakesDynamic Brake Control (DBC)*DBC is included in the DSC, refer to
information beginning on page 74.
If you step on the brake rapidly, this
system automatically produces
maximum braking force boost and thus
helps to achieve the shortest possible
braking distance during "panic stops".
All of the benefits of the ABS system
are exploited under these circum-
stances.
Do not reduce the pressure on the
brake pedal for the duration of the
brake application. When the brake
pedal is released, the DBC is deacti-
vated.
In the event of a malfunction,
the brake warning lamp lights up
yellow. Normal braking effi-
ciency is still fully available.
Have the system checked and
repaired at your BMW center as
soon as possible.
Please observe the section "Infor-
mation for your safety" concerning
the ABS system, which also applies to
the DSC system.<
Disc brakes furnish optimum decelera-
tion and braking control and greater
fade resistance under heavy use.
When the vehicle is driven only occa-
sionally, during extended periods when
the vehicle is not used at all, or in oper-
ating conditions where brake applica-
tions are less frequent, there is an
increased tendency for corrosion of the
rotors and accumulation of contamina-
tion on the brake pads. This occurs
because the minimal pressure which
must be exerted by the pads to clean
the rotors by brake applications is not
reached.
If the brake rotors are corroded, they
will tend to respond to braking with a
pulsating effect which even extended
application will fail to cure.
For your own safety: use only
brake pads that BMW has
approved for your specific vehicle
model. BMW cannot evaluate non-
approved brake pads to determine if
they are suited for use, and therefore
cannot ensure the operating safety of
the vehicle in the event of their use.<
Driving notesWhile driving in wet conditions and in
heavy rain, it is advisable to apply light
pressure to the brake pedal every few
miles Ð watch traffic conditions to
ensure that this maneuver does not
endanger other road users. The heat
generated in this process helps dry the
pads and rotors.
Maximum braking force is obtained
while the wheels continue to rotate,
peaking when the wheels remain on the
verge of locking without actually doing
so. ABS maintains this state automati-
cally. If the ABS fails, you should revert
to the staggered braking technique
described on page 106.
Extended or steep mountain descents
should be driven in the gear in which
only minimal periodic brake application
is required. This avoids excessive strain
on the brakes and possible
impairment of the braking effect.
You can increase the engine's braking
effect by selecting progressively lower
gears, downshifting into first gear, if
necessary. You can also downshift into
first gear if you are using the manual
mode in a vehicle with automatic trans-
mission, refer to page 63.

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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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Information for your safetyThe factory-approved radial tires are
matched to the vehicle and have been
selected to provide optimum safety and
driving comfort on your vehicle.
In a very real sense, both tire life and
your own safety are riding on correct
tire specifications and inflation pres-
sures, refer to page 26.
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 pressures,
including the spare tire, on a regular
basis, at least twice a month and before
doing any extended driving, refer to
page 26. If this is not done, incorrect
tire pressures can cause driving insta-
bility and tire damage, ultimately
resulting in accidents.<
Check the inflation pressure of
the spare tire For checking tire pressures, there is a
valve extension (arrow) on the storage
tray of the spare wheel which is acces-
sible from outside.367de309
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 pattern 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 390de331
Notes on inflation pressures Tire condition

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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.<

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IndexDataTechnologyRepairsMaintenanceControlsOverview
Tire replacement Tire rotationTire ageThe date on which the tire was manu-
factured is indicated by the code on the
sidewall:
DOT ... 2501 indicates that the tire was
manufactured in week 25 of 2001.
BMW recommends the replacement
of all tires when the tires are no more
than 6 years old, even if a tire usage of
10 years is possible.
Spare tires over 6 years old should be
used only in case of emergency. A tire
of this age should be replaced by a new
tire immediately, and should not be
fitted together with new tires.
Between the axlesTread wear at the front and rear axle is
different and will vary according to indi-
vidual driving conditions. In the interest
of safety and optimal vehicle response,
we advise against rotating tires from
front to rear and vice versa.
If rotating the tires between the axles is
under consideration for economic
reasons, the costs for remounting the
wheels must be calculated against any
savings which might result from the
anticipated extension in tire life. Rota-
tion should always be carried out at
short intervals, with a maximum of
3,000 miles (5,000 km). Consult your
BMW center for more information.Should you decide to rotate the tires,
it is essential to comply with the
following:
Rotate wheels on the same side of the
vehicle only, otherwise braking effi-
ciency and road grip could be adversely
affected.
Following rotation, correct the tire infla-
tion pressure.
If tires with different sizes are
mounted on the front and rear
axles (refer to the information beginning
on page 116), the wheels may not be
rotated from one axle to the other.<

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Wheel and tire combinationsThe right choice
Use only wheels and tires
approved by BMW for the corre-
sponding vehicle model, as otherwise
the tires may make contact with the
body as the result of tolerances despite
the same nominal size being used,
resulting in serious accidents. If non-
approved wheels and tires are used,
BMW cannot evaluate their suitability,
and therefore cannot be held liable for
driving safety.<
For wheel and tire specifications
approved by BMW, refer to the informa-
tion beginning on page 116.
The correct wheel and tire combi-
nation affects different systems
such as ABS and ASC+T/DSC
*. The
function of these systems is impaired if
improper wheel and tire combinations
are used.
For this reason, use only tires of the
same manufacture and tread configura-
tion. In the event of a flat tire, for
example, remount the approved wheel
and tire combination as soon as
possible.<
Codes on tires and wheelsThe code on the tires has the following
meaning.
Codes on radial tires:
The speed rating indicates the
approved maximum speed for the tire.
Summer tires:
S = up to 112 mph (180 km/h)
T = up to 118 mph (190 km/h)
H = up to 130 mph (210 km/h)
V = up to 149 mph (240 km/h)
W = up to 167 mph (270 km/h)
Y = up to 186 mph (300 km/h)
ZR = over 149 mph (240 km/h) Example:
Nominal width
in mm
Aspect ratio in %
Belt rating ID code
for radial tires
Wheel diameter in inches
Load rating
(not on ZR tires)
Speed rating
(before R on ZR tires)
205/60 R 15 91 H
All season and winter tires:
Q M+S = up to 100 mph (160 km/h)
T M+S = up to 118 mph (190 km/h)
H M+S = up to 130 mph (210 km/h)
Codes on light-alloy wheels:
Protect valve inserts against dirt by
using screw-on valve caps. Dirt in the
valve inserts frequently causes a slow
loss in tire pressure.Storage Store tires in a cool, dry place,
protecting them against light whenever
possible. Protect the tires against
contact with oil, grease and fuel. Example:
Rim width
in inches
Code letter for
flange type
Symbol for full-drop
center rim
Rim diameter in inches
Hump on the 2 rim shoulders
7x15H2
J