wheel BMW M3 CONVERTIBLE 2004 E46 Owner's Guide

118Wheels 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. If this is not done, incorrect tire
pressures can cause driving instability
and tire damage, ultimately resulting in
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.

119
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.
This can result in a sudden loss of tire
inflation pressure.
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-
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 replacementTo maintain good handling characteris-
tics, only use a full set of tires of the
same brand and tread configuration.
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.DOT 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.
Tire condition
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120
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.
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. applicable on the tire sidewall between
tread shoulder and maximum section
width. For example:
Treadwear 200 Traction AA
Temperature A
Tire ageThe date on which the tire was manu-
factured is indicated by the code on the
sidewall:
DOT ... 3603 indicates that the tire was
manufactured in week 36 of the year
2003.
BMW recommends the replacement of
all tires when the tires are no more than
6 years old, even if a tire life of 10 years
is possible.Following wheel/tire changesComply 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.
Following wheel and/or tire changes
you will need to reinitialize both the
sequential M gearbox with Drivelogic
and the Flat Tire Monitor, refer to
pages 74, 88.
Tire replacement

121
Wheel and tire combinationsThe right choice
BMW recommends using only
wheels and tires that have been
approved by BMW for your particular
vehicle model, as otherwise body con-
tact and serious accidents can result
despite the use of the same nominal
size, e.g. due to manufacturing toler-
ances. If non-approved wheels and
tires are used, BMW cannot evaluate
their suitability, and therefore cannot be
held liable for driving safety.<
BMW tests certain tire brands for each
tire size, classifies them as road-safe
and approves them. Consult your BMW
center for more information. Observe
any country-specific regulations, e.g.
on making a corresponding entry in the
vehicle documents.
The correct wheel and tire combi-
nation affects different systems
such as ABS, DSC, Flat Tire Monitor.
The function of these systems is
impaired if improper wheel and tire
combinations are used.
Therefore, only use tires of the same
brand and same tread configuration on
the vehicle and, for example following a
tire failure, restore the approved wheel
and tire combination as soon as possi-
ble.<
The use of rims and lug bolts that
do not meet the specifications of
the original factory-installed equipment
will affect the safe operation of your
vehicle and may cause an accident and
personal injury.
Never mix tires of different design, such
as steel-belted radials with radial bias-
belted or bias-ply tires, etc. Mixing tire
types will adversely affect roadholding
and can lead to loss of vehicle con-
trol.<
StorageAlways store tires in a cool, dry place.
Store them away from light whenever
possible. Protect the tires against con-
tact with oil, grease and fuel.
Do not exceed the maximum tire infla-
tion pressures specified on the tire
sidewall.
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122
Winter tiresChoosing the right tireBMW recommends the use of winter
tires for operation under winter road
conditions. While all-season tires – with
M+S designation – provide better winter
traction than the corresponding sum-
mer tires, they generally do not achieve
the performance of winter tires.
In the interest of safe tracking and
steering response, install radial tires
made by the same manufacturer and
with the same tread configuration on all
four wheels if you elect to mount winter
tires.
When mounting winter wheels,
observe the different recesses of
the front and rear wheels, as otherwise
damage may result.<
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 depths below approx. 3/16 in /
4 mm, tire 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 with Drivelogic, refer to
page 88.
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 87.<

140
Center high-mount brake lampLED strip in luggage compartment lid.
Please contact a BMW center in case of
a malfunction.
License plate lamps5 watt bulb
1. Place a screwdriver in the slot and
press toward the left to release the
lens
2. Replace the bulb.
Repairing a flat tire
Precautions in case of a flat tire:
Stop the vehicle as far as possible
from passing traffic; switch on the haz-
ard warning flashers.
Turn the steering wheel to the straight-
ahead position and engage the steering
lock. Shift into 1st or reverse and
engage the parking brake.
All passengers should be outside the
vehicle and well away from your imme-
diate working area – behind a guardrail,
for instance.
If necessary, set up your warning trian-
gle or portable hazard warning lamp on
the roadside at an appropriate distance
from the rear of the vehicle. Comply
with all safety guidelines and regula-
tions.<
M Mobility systemYou will find an M Mobility system in
your BMW M3 Convertible for repairing
flat tires. With this system you can
apply a sealing liquid to the inside of
the tire that seals off the damaged point
and then continue driving.
The M Mobility system makes trans-
porting a spare wheel superfluous,
thereby reducing the amount of weight
you have to carry around.
Lamps and bulbs

141
Using the M Mobility systemTo repair a flat tire using the M Mobility
system, proceed as follows:
>Preparing the M Mobility system for
use, refer to the next column
>Components of the M Mobility sys-
tem, refer to page 142
>Filling with sealant, refer to page 142
>Distributing sealant, refer to
page 143
>Inflating tire to correct pressure, refer
to page 143.
Preparing the M Mobility system
for useThe M Mobility system is located in the
luggage compartment under the floor
panel:
1. Lift the floor panel
2. Loosen the M Mobility system from
its storage location.
Before you use the M Mobility sys-
tem, read the warnings and dan-
ger notices on the device carefully.<
If possible, leave the foreign object in
the tire.
Pull off the sticker 5, refer to the second
column below, for the speed limit and
apply it to the steering wheel.
Please keep in mind that the fluids
bottle in the system's sealant con-
tainer has to be changed every 3 years
by your BMW center, if the unit has not
been used.<
Repairing a flat tire
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142
Components of the M Mobility
system1On/Off switch
2Connection hose with manometer for
connecting the compressor with the
sealant container or to connect the
compressor to the wheel
3Manometer for indicating the tire
pressure
4Connector hose from the sealant
container to the wheel
5Sticker with speed limit
6Plug and cable for the cigarette
lighter socket
7Protective gloves, not shown
Filling with sealant1. Take off the round cover and take out
hose 4. Unscrew the valve dust cap
from the defective wheel and screw
the hose to the valve. Keep the dust
cap in a safe place
2. Flip open the cover and pull out the
enclosed protective gloves. Take out
hose 2 with the manometer and
screw it to the terminal for the seal-
ant container as shown in the illustra-
tion
3. Make sure that the system has been
switched off, position 0.
Take out plug 6 and insert it into the
cigarette lighter socket in the pas-
senger compartment, refer to
page 103
Repairing a flat tire

143
4. Make sure that the screw on the rear
of the pressure gauge 3 is tightened
down. Turn on the M Mobility sys-
tem, position I, refer to illustration,
and allow minutes to elapse, to let
the sealant flow in. It does not matter
afterward, what the tire's inflation
pressure is
5. Turn the system off.
Disconnect the connector hose from
the sealant container and the wheel
valve. Stow the M Mobility system in
the luggage compartment.Distributing the sealantRight afterward, drive at least
1 1/4 miles / 2 km, so that the liquid
sealant distributes evenly throughout
the inside of the tire.
Do not exceed a maximum speed
of 40 mph / 60 km/h. If possible,
keep the vehicle speed above 10 mph /
20 km/h.
Stop in a suitable spot.<
Inflating tire to correct pressure1. Take out the hose with the pressure
gauge and screw it onto the valve.
Take the plug out and plug it into the
cigarette lighter socket in the pas-
senger compartment
2. Reset the air pressure to
29 psi/200 kilopascal, and:
>Increase tire pressure: switch on
the M Mobility System, position I.
Switch off the unit briefly to check
the current tire pressure
>Decrease tire pressure: turn the
screw on the back of the manome-
ter, a valve located there will open
Repairing a flat tire
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144
Even if the tire fails to hold the
pressure, you should still carry out
Step 3 before proceeding to drive the
vehicle again, refer to Distributing the
sealant for more information. Then
repeat Steps 1 through 3.
The use of the M Mobility system may
be ineffective if the damaged area in
the tire is larger than approx. 1/8 in /
4 mm. Please consult the nearest BMW
center if the tire cannot be temporarily
repaired with the M Mobility system.<
3. Unscrew the hose from the valve and
stow the M Mobility system in the
luggage compartment. Screw the
dust cap onto the valve again.
Do not exceed the maximum
speed limit described below, oth-
erwise it could lead to accidents.<
When you start driving again, do not
exceed the permissible maximum
speed of 45 mph / 80 km/h.
You will find corresponding
instructions for using the
M Mobility system on the device.
Replace the defective tire as soon as
possible and have the new wheel bal-
anced. Reinitialize the Flat Tire Monitor,
and refer to page 88 for further informa-
tion. Have the M Mobility system
refilled. Contact your BMW center for
this.<
Protect valve stems against dirt using
screw-on dust caps. Dirty valve stems
frequently lead to slow pressure loss.
Battery
Battery posts, terminals, and
related accessories contain lead
and lead compounds. Wash hands after
handling.<
MaintenanceThe battery is completely maintenance-
free. That means that the original bat-
tery acid will normally last for the ser-
vice life of the battery under moderate
climate conditions.
Please consult your BMW center
whenever you have any questions
concerning the battery. when the engine is not running. Use the
connections provided in the engine
compartment. For information on the
connections, see Jump-starting,
page 147.Disposal
Return used batteries to a recy-
cling point or your BMW center.
Maintain the battery in an upright posi-
tion for transport and storage. Secure
the battery against tilting in transit.<
Repairing a flat tire