2002 BMW Z3 air condition

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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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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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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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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 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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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.

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Engine oil To check oil level1. Park the vehicle on a level surface
2. Switch the engine off after it has
reached normal operating tempera-
ture
3. After approx. 5 minutes, pull the
dipstick out and wipe it off with a
clean lint-free cloth, paper towel, or
similar material
4. Push the dipstick carefully all the way
into the guide tube and pull it out
again
5. The oil level should be between the
two marks on the dipstick.
As with fuel economy, oil consumption
is directly influenced by your driving
style and vehicle operating conditions.367de738
The space between the two marks on
the dipstick corresponds to approx.
1.1 US quarts (1 liter). Do not fill beyond
the upper mark on the dipstick. Excess
oil will damage the engine.460de189
To add oilWhile you should wait until the level has
dropped to just above the lower mark
before adding oil, you should never
allow the oil level to fall below this
mark.
BMW engines are designed to
operate without oil additives; the
use of additives could lead to damage
in some cases. This also applies to the
manual and automatic transmission, the
differential and the power steering
system.< 367de344

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The BMW Maintenance SystemService and Warranty Information
Booklet (US models)/Warranty
and Service Guide Booklet
(Canadian models)For detailed information on required
maintenance items and the work
involved, please refer to the Service
and Warranty Information Booklet (US
models) or to the Warranty and Service
Guide Booklet (Canadian models).
Depending upon operating conditions,
it may be advisable to have the body
checked for damage from rocks or
gravel as a precaution against rust.Have your BMW center perform
the maintenance and repair.
Your BMW center is always informed on
the latest maintenance work and repair
techniques and is equipped with the
required special tools. In addition,
checking parts known from experience
to be subject to wear is a permanent
part of the maintenance specifications.
Be sure that all maintenance work is
confirmed in the Service and Warranty
Information Booklet (US models) or the
Warranty and Service Guide Booklet
(Canadian models). These entries will
constitute your proof that the vehicle
has received regular maintenance. They
are also required for warranty claims.<