2002 BMW Z3 ESP

106n
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
Cellular phone
*
Car radio reception
Mobile communications systems
(cellular phones, two-way radios, etc.)
are approved only up to a power output
of 10 watts. Nonetheless, they may
cause interference in the operation of
your vehicle if they are not specifically
designed for use in your vehicle. BMW
can neither test nor assume responsi-
bility for every individual product being
offered on the market. We recommend
that you consult your BMW center
before purchasing any device of this
kind.
To ensure that your BMW continues to
provide reliable and trouble-free opera-
tion, refrain from using a cellular phone
or other radio device with an antenna
located inside the passenger compart-
ment. The antenna should always be
fitted on the outside of the vehicle.
Before loading the vehicle on
a car-carrier train or driving it
through a car wash, remove the
antenna.<
The reception and sound quality
obtained from mobile radios varies
according to a variety of factors,
including the broadcast range of the
transmitter and the directional orienta-
tion of the antenna. Interference factors
such as high-tension power lines, build-
ings and natural obstructions can all
lead to unavoidable reception interfer-
ence, regardless of how well the
vehicle's sound system is operating.
Climatic factors such as intense solar
radiation, fog, rain and snow can also
interfere with reception.
Cellular phones without official BMW
approval can also generate interference
during use. This phenomenon assumes
the form of a low-pitched hum
emanating from the speaker system.
Please refer to the Owner's Manual
provided with your sound system for
detailed information on its use.Whenever necessary (when
entering a car wash, for instance),
remove the rod antenna
*. To remove
the antenna, grasp the rod at the
bottom and unscrew it to the left from
the antenna base.<
You will find additional information
concerning car radio reception in the
chapter "Advanced technology" on
page 166.

108n
Hardtop
* Ð roadster
The fabric top does not have to be
removed even in winter, when the
hardtop is normally in constant use. In
order to prevent water spots and
mildew stains, the fabric top must be
completely dry before it is stored in the
convertible top compartment.
Two people are necessary for the
installation and removal of the hardtop.
Work with extreme caution during this
operation to avoid paint damage and
damage to the body and hardtop.
You may purchase a hardtop lift
* from
your BMW center. This accessory is
especially designed to facilitate installa-
tion and removal of the hardtop.
InstallationHook the protective fabric on the
convertible top linkage (arrow).
Open the convertible top and fold it
down in the convertible top compart-
ment, refer to pages 40 and 44.
When doing this, make sure the rear
window is laid down evenly and free
of creases. To prevent the rear window
from being scratched, position the
protective fabric in the window fold.
Do not install the convertible top cover.
Lower the side windows and remove
the rod antenna if necessary to avoid
damage.367de384
Rotate the cover panel which is located
in the right and left trim panels behind
the seats in the direction of the arrow
until the opening for the hardtop mount
is completely free.
Remove the hardtop from the protec-
tive cover. Clean any dirt and dust from
the contact surfaces between the
hardtop and the vehicle body in order
to protect against abrasion.
Position the hardtop on the mounts with
the assistance of a second person.367de385

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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.

112n
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.<

114n
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

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IndexDataTechnologyRepairsMaintenanceControlsOverview
Special features of winter tires Snow chains
*
Choosing the right tireBMW recommends winter tires (M+S
radial tires) for operation under
inclement winter driving conditions.
While so-called all season tires (M+S
designation) provide better winter trac-
tion than summer tires with the load
ratings H, V, W, Y and ZR, they gener-
ally do not achieve the performance of
winter tires.
In the interests of sure tracking and safe
steering response, mount winter tires
which are made by the same manufac-
turer and which have the same tread
configuration at all four wheels.Comply with recommended speed
Never exceed the maximum
speed for which the winter tires
are rated.
Unprofessional attempts by laymen to
service tires can lead to damage and
accidents.
Have this work performed by skilled
professionals only. Any BMW center
has the required technical knowledge
and the proper equipment and will be
happy to assist you.<
Tire condition, tire pressureOnce the tire wears to below 0.16 in
(4 mm), winter tires display a percep-
tible decrease in their ability to cope
with winter driving conditions, and
should be replaced in the interest of
safety.
Comply with the specified tire inflation
pressures Ð and be sure to have the
wheel and tire assemblies balanced
every time you change the tires.BMW narrow-link snow chains are
intended for mounting in pairs at the
rear wheels only. Comply with all manu-
facturer's safety precautions when
mounting the chains. Do not exceed a
speed of 30 mph (50 km/h) while
driving with mounted snow chains.