2003 BMW M3 CONVERTIBLE service

115 Wheels and tires
Tire inflation pressureInformation for your safetyThe factory-approved tires are matched
to your vehicle and have been selected
to provide optimum safety and driving
comfort when used properly.
It is not merely the tire's service life, but
also driving comfort and – above all else
– driving safety that depend on the con-
dition of the tires and the maintenance
of the specified tire pressure.
Incorrect tire inflation pressure is
a frequent cause of tire damage. It
also significantly influences the road-
holding ability of your BMW. Check tire
inflation pressures on a regular basis,
refer to page 25, at least every two
weeks and before beginning a longer
trip. Incorrect tire pressure can other-
wise lead to driving instability, tire dam-
age and accidents.<
Tire conditionTire tread – tire damageInspect your tires frequently for tread
wear, signs of damage and for foreign
objects lodged in the tread. Check the
tread depth.
Tread depth should not be allowed to
go below 1/8 in / 3 mm, even though
the legally specified minimum tread
depth is only 1/16 in / 1.6 mm.
Below 1/8 in / 3 mm tread depth, there
is a great risk of hydroplaning, even at
relatively moderate speeds and with
only small amounts of water on the
road. Tread wear indicators in the
tread-groove base – see arrow – are
distributed around the wheel circumfer-
ence and are labeled on the tire side-
wall with TWI – Tread Wear Indicator. At
a tread depth of 1/16 in / 1.6 mm, the
indicators signal that the legally permis-
sible wear limit has been reached.
Do not drive 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 can lead to
overheating and internal tire damage.
You could have a blowout as a result.
Unusual vibrations encountered during
normal vehicle operation can indicate
tire failure or some other vehicle defect.
This type of problem can be caused by
contact with curbs, etc. This is also true
for irregularities in the vehicle's han-
dling characteristics, such as a pro-
nounced tendency to pull to the left or
right. Should this occur, respond by
immediately reducing your speed. Pro-
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116
ceed carefully to the nearest BMW cen-
ter or professional tire center, or have
the vehicle towed in to have it, its
wheels or its tires inspected.
Tire damage, up to and including blow-
outs, can endanger the lives of both the
vehicle occupants and other road
users<
Tire replacementDOT quality grades>Treadwear
>Traction AA A B C
>Temperature A B C
All passenger car tires must con-
form to Federal Safety Require-
ments 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 – 1
1/2 – 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. 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 tem-
perature 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 Standard No. 109.
Tire condition
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119
Do not exceed specified
maximum speeds
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. Your BMW center
will be glad to assist you with both their
expertise and the proper equipment for
your vehicle.<
Tire condition, tire pressureAt tread depth below approx. 3/16 in /
4 mm, their performance under winter
driving conditions deteriorates notice-
ably. Worn tires should therefore be
replaced for safety considerations.
Comply with the specified tire inflation
pressures – and be sure to have the
wheel and tire assembly balanced
every time you change a tire or wheel.
Snow chains*Only certain snow chains have been
tested by BMW and determined and
approved as roadworthy. Consult your
BMW center for more information.
BMW recommends using only these
approved fine-link snow chains. Use
them in pairs on winter tires, but only on
both rear wheels.
Comply with all manufacturer's safety
precautions when mounting the chains.
Do not exceed a speed of 30 mph /
50 km/h with snow chains.
After mounting or removing snow
chains, always reinitialize the sequential
M gearbox SMG II, refer to page 89.
It is not possible to mount snow
chains on tires with 18- and 19-
inch wheels.
Deactivate the Flat Tire Monitor when
using snow chains. Malfunction warn-
ings and undetected losses in pressure
are a possibility when driving with snow
chains.
For additional information, refer to
page 88.<
Winter tires
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120In the engine compartment
HoodTo releasePull the lever located under the left-
hand side of the instrument panel.
Do not attempt to service your
vehicle if you do not have the
required technical background. Failure
to work in an informed, professional
manner when servicing components
and materials constitutes a safety haz-
ard for vehicle occupants and other
road users. If you are not familiar with
the guidelines, please have the opera-
tions performed by your BMW center.<
To openPull the release handle and open the
hood.
It is not possible to drive off using
SMG II when the hood is open.<
To closePull the hood downwards and allow the
hood to fall from a minimum height of
1 ft/30 cm so that it audibly engages.
Check for proper locking by pulling on
the hood at the left and right above the
headlamps.
To avoid injuries, be sure that the
travel path of the hood is clear
when it is closed, following the same
safety precautions used in all closing
procedures.
If you notice while driving that the hood
is not completely closed, stop immedi-
ately and close it securely.<
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127
3. If necessary, add coolant. If the cool-
ant is low, slowly add coolant until
the correct level is reached — do not
overfill.
Comply with the applicable envi-
ronmental laws regulating the dis-
posal of antifreeze agents with corro-
sion inhibitor.<
Brake fluidIndicator lamp
The brake warning lamp comes
on when the parking brake is
not engaged: brake fluid level
too low, refer to page 18.
Brake warning lamp for Cana-
dian models.
Adding brake fluidFor adding brake fluid or for determin-
ing and correcting the cause of brake
fluid loss, consult your BMW center.
Your BMW center is familiar with the
specifications for factory-approved
brake fluids – DOT 4.
Due to loss in brake fluid, pedal travel
can lengthen and braking efficiency
may be reduced. Refer to the informa-
tion on page 112.
Brake fluid is hygroscopic, that is,
it absorbs moisture from the air
over time.
In order to ensure the safety and reli-
ability of the brake system, have the
brake fluid changed every two years by
a BMW center. Refer also to the Service
and Warranty Information Booklet for
US models or the Warranty and Service
Guide Booklet for Canadian models.
Brake fluid is toxic and damages the
vehicle's paint. You should always store
it in its closed original container and in
a location inaccessible to children.
Do not spill the brake fluid and do not
fill the brake fluid reservoir beyond the
MAX mark. The brake fluid could ignite
upon contact with hot engine parts and
cause serious burns.<
Comply with the applicable envi-
ronmental laws regulating
the disposal of brake fluid.<
Coolant
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128Maintenance
The BMW Maintenance SystemThe BMW Maintenance System has
been designed as a reliable means of
providing maximum driving and operat-
ing safety – and as cost-effectively for
you as possible. Please keep in mind
that regular maintenance is not only
necessary for the safety of your vehicle,
but also plays a significant role in main-
taining the resale value of the vehicle.Service interval displayWhile conventional systems rely on dis-
tance traveled alone to determine when
service is due, the BMW Maintenance
System has for years taken the actual
conditions under which the vehicle
operates into consideration, because
miles can be traveled in many different
ways:
For example, 62,000 miles/100,000 km
short-distance driving are not equal to
the same 62,000 miles/100,000 km of
long-distance travel.
The BMW Maintenance System
includes the Engine Oil Service and
Inspections I and II.
Have a break-in inspection per-
formed at 1,250 miles/2,000 km
regardless of the service interval indi-
cated on the display.<
Determining the maintenance intervals
according to the actual loads on the
vehicle covers every kind of operating
situation. Minimal-use drivers – who
drive significantly fewer than
6,200 miles/10,000 km annually –
should have the engine oil changed at
least every 2 years since oil deterio-
rates over time, regardless of use.
Service and Warranty Information
Booklet for US models/Warranty
and Service Guide Booklet for
Canadian modelsFor additional information on required
maintenance intervals and procedures,
please refer to the Service and War-
ranty Information Booklet for US mod-
els, or the Warranty and Service Guide
Booklet for Canadian models.
As a precaution against corrosion, it is
advisable to have the body checked for
damage from rocks or gravel at the
same time, depending upon operating
conditions.
Have your BMW center perform
maintenance and repair.
Be sure that all maintenance work is
recorded in the Service and Warranty
Information Booklet for US models, or
in the Warranty and Service Guide
Booklet for Canadian models. These
entries are your verification for the reg-
ular maintenance of your vehicle and
are required for the performance of
warranty repairs.<
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130Laws and regulations
California Proposition 65 warningCalifornia laws require us to state the
following warning:
Engine exhaust, some of its con-
stituents, and certain vehicle com-
ponents contain or emit chemicals
known to the State of California to
cause cancer and birth defects and
reproductive harm. In addition, certain
fluids contained in vehicles and certain
products of component wear contain or
emit chemicals known to the State of
California to cause cancer and birth
defects or other reproductive harm.
Battery posts, terminals and related
accessories contain lead and lead com-
pounds. Wash your hands after hand-
ling.
Used engine oil contains chemicals that
have caused cancer in laboratory ani-
mals. Always protect your skin by
washing thoroughly with soap and
water.<
OBD interface socketThe Onboard Diagnostic (OBD) inter-
face socket is located on the left of the
driver's side at the bottom of the instru-
ment panel and under a cover. The
cover has the letters OBD on it.
The purpose of the OBD system is to
assure proper emission-control system
operation for the vehicle's lifetime by
monitoring emission-related compo-
nents and systems for deterioration and
malfunction.
An illuminated indicator informs
you of the need for service, not
that you need to stop the vehi-
cle. However, the systems should be
checked by your BMW center at the
earliest possible opportunity.
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131
If the indicator blinks or flashes, this
indicates a high level of engine misfire.
Reduce speed and contact your near-
est BMW center immediately. Severe
engine misfiring for even a short period
of time can seriously damage emission-
control system components, especially
the catalytic converter.
Service Engine Soon warning
lamp for Canadian models.
If the fuel filler cap is not on tight
enough, the OBD system can
detect leaking vapor and the indicator
will light up. If the fuel filler cap is then
tightened, the indicator will usually go
out after a short period of time. OverviewControlsMaintenanceRepairsDataIndex
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