2006 BMW Z4 3.0SI ROADSTER tire pressure

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51
Malfunction
The warning lamp for the brake system
lights up in yellow. The drive-off assis-
tant has failed. The car will not be held
in place after the brake is released. Have the
system checked as soon as possible.
Flat Tire Monitor FTM
The concept
The Flat Tire Monitor monitors tire pressures
while the car is being driven. The system
reports any significant loss of pressure in one
tire in relation to another.
In the event of tire pressure loss, the rolling
radius of the tire changes, thereby affecting the
rotational speed of the wheels. This change is
detected, and a flat tire warning is issued to the
driver.
System requirements
To ensure a reliable flat tire warning, the system
must be initialized with the correct tire inflation
pressures.
The system must be reinitialized each
time a tire inflation pressure has been cor-
rected or a wheel or tire has been changed.<
System limitations
The Flat Tire Monitor is unable to warn
the driver of sudden, severe tire damage
caused by external factors, nor can it identify
the gradual loss of pressure that will inevitably
occur in all four tires over a lengthy period of
time.<
The system could issue a false warning or func-
tion in a delayed manner in the following situa-
tions:
>System was not initialized
>Driving on a snow-covered or slippery road
surface
>Performance-oriented driving: slip at the
drive wheels, high levels of lateral accelera-
tion
>Driving with snow chains attached
Initializing the system
The initialization is completed while you
are driving, and can be interrupted at any
time. Initialization is continued automatically
when you continue driving.
When driving with snow chains, do not initialize
the system.<
1.Start the engine immediately before pulling
away, but do not drive off yet.
2.Press the button until the yellow indicator
lamp in the instrument cluster lights up for a
few seconds.
3.Drive off.
Initialization is completed during the drive,
without any feedback issued.
Flat tire warning
The warning lamp in the instrument
cluster lights up in red. A signal also
sounds. There is a flat tire or a signifi-
cant loss of tire pressure.
1.Cautiously reduce speed to 50 mph/
80 km/h or lower. Avoid strong braking and
steering maneuvers. Do not exceed a maxi-
mum speed of 50 mph/80 km/h.
If the car is not equipped with Run-
Flat Tires, refer to page84, the stan-
dard equipment by design, do not continue
driving. Otherwise a severe accident could
result after a tire puncture.<
2.At the next opportunity, check the air pres-
sure in all four tires.
If the inflation pressure is correct in all
four tires, it is possible that the Flat
Tire Monitor was not initialized. In this case,
initialize the system.<

Technology for driving comfort and safety
52 3.In the event of complete tire pressure loss,
0 psi/0 kilopascal, you can estimate the
possible distance for continued driving on
the basis of the following guidelines:
>With a light load:
1 person without luggage:
approx. 155 miles/250 km
>With a medium load:
1 person, cargo bay full,
or
2 persons without luggage:
approx. 90 miles/150 km
>With a full load:
2 persons, cargo bay full:
approx.30miles/50km.
Drive cautiously. Do not exceed a speed
of 50 mph/80 km/h. Driving characteris-
tics change if there is a loss of tire pressure.
This includes reduced tracking stability in brak-
ing, extended braking distance and altered nat-
ural steering characteristics.
If unusual vibration or loud noises occur during
the journey, this may be an indication that the
damaged tire has finally failed. Reduce your
speed and pull over to the side of the road at the
earliest opportunity. Otherwise, parts of the tire
could come loose and cause an accident. Do
not continue driving. Contact a BMW Center.<
Electric Power Steering EPS
The concept
The electric power steering is a direct, sporting
steering system. A special combination of elec-
tric motor and transmission helps you steer
more easily. As your speed increases, steering
power assistance is reduced.
Malfunction
The indicator lamp stays lit:
The system is malfunctioning or defec-
tive.
Steering remains operational.
Have the system checked as soon as possible.
Brake Force Display
The brake lamps light up in two stages,
depending on how sharply you apply the
brakes.
>Normal braking:
The brake lamps and the center brake lamp
light up.
>Sharp braking:
A larger portion of the brake lamps lights up.
Airbags
The following airbags are located under the
marked covers:
1Front airbags
2Side airbags
3Knee airbags
Protective action
Comply with the instructions on page30,
or the occupants' personal safety will be
diminished.<
The front airbags help protect the driver and
passenger in the event of a frontal impact in
which safety belts alone cannot provide suffi-
cient protection. When needed, the side airbags

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cannot be ruled out that vehicle electronics and
the mobile communications device interfere
with one another. In addition, it is not ensured
that the radio waves emitted during transmis-
sion are directed outside of the vehicle inte-
rior.<
Interior and exterior mirrors with
automatic dimming feature*
The automatic dimming feature of the interior
and exterior mirrors
* is controlled by two photo
cells in the interior rearview mirror. In the Road-
ster, one is located in the mirror glass, see
arrow. In the Coupe, it is located at the bottom
of the mirror frame. The other photo cell is on
the back of the mirror.
In order to ensure that the system functions
correctly, keep the photocells clean, do not
cover the area between the interior rearview
mirror and windshield, and do not affix adhesive
labels or stickers of any kind to the windshield
directly in front of the mirror.
Hydroplaning
When driving on wet or slushy roads,
reduce vehicle speed. If you do not, a
wedge of water may form between the tires and
the road surface. This situation, known as
hydroplaning, means that the tire can com-
pletely lose contact with the road surface, so
that neither the car can be steered nor the brake
be properly applied.<
The risk of hydroplaning increases with declin-
ing tread depth on the tires, refer also to Mini-
mum tread depth on page83.
Driving through water
Drive through water on the road only if it is
not deeper than 1 ft/30 cm, and then only
at walking speed at the most. Otherwise, the
vehicle's engine, the electrical systems and the
transmission may be damaged.<
Moisture inside the vehicle
Make sure that the passenger compart-
ment does not become wet and that liq-
uids are transported in closed containers.
Otherwise, moisture could penetrate and dam-
age electronic components inside the vehicle.<
Use the parking brake on inclines
On inclines, keep the vehicle from rolling
by using the parking brake rather than by
slipping the clutch, which would lead to a high
degree of clutch wear.<
Braking safely
Your BMW is equipped with ABS as a standard
feature. Applying the brakes fully is the most
effective way of braking in situations in which
this is necessary. Since the vehicle maintains
steering responsiveness, you can still avoid
possible obstacles with a minimum of steering
effort.
Pulsation at the brake pedal combines with
sounds from the hydraulic circuits to indicate to
the driver that ABS is in its active mode.
Wet roads
When roads are wet or there is heavy rain,
briefly exert gentle pressure on the brake pedal
every few miles. Watch traffic conditions to
ensure that this maneuver does not endanger
other road users. The resulting heat dries the
brake rotors and brake pads. Immediate braking
force is then available if necessary.
Inclines
To prevent overheating and, as a result,
diminished braking effectiveness, drive
down long or steep downhill grades in the gear
that requires the least braking. Otherwise, even
light but consistent pedal pressure can lead to

Special operating instructions
72 high temperatures, brake wear and possibly
even brake failure.<
You can increase the engine's braking effect by
shifting down, all the way to first gear if neces-
sary. This strategy helps you avoid placing
excessive loads on the brake system. Down-
shifting in manual mode of the automatic trans-
mission, refer to page41.
Never drive with the clutch held down,
with the transmission in idle or with the
engine switched off; otherwise, engine braking
action will not be present or there will be no
power assistance to the brakes or steering.
Never allow floor mats, carpets or any other
objects to protrude into the area around the
pedals, otherwise pedal function could be
impaired.<
Corrosion on the brake rotors
Limited vehicle use, extended periods with the
vehicle parked or in storage, and operating con-
ditions in which braking is restricted to gentle,
low-pressure applications will all increase the
tendency for corrosion to form on the rotors and
contamination to accumulate on the brake
pads. This occurs because the minimal pres-
sure 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.
When the vehicle is parked
Condensation forms while the air conditioning
or automatic climate control is in operation, and
then exits under the vehicle. Traces of con-
densed water on the ground underneath the
vehicle are thus normal.
Before driving into a car wash
For general information about taking care of
your BMW, refer to the Caring for your vehicle
brochure.
Cargo loading
Avoid overloading the vehicle so that the
permissible carrying capacity of the tires
is not exceeded. Otherwise, overheating and
inner damage to the tires may result. The ulti-
mate result can assume the form of a sudden air
loss.<
Determining the maximum load
1.Locate the following statement on your
vehicle's placard
*:
The combined weight of occupants
and cargo should never exceed
XXX kg or YYY lbs. Otherwise, overloading
can result in damage to the vehicle and
unstable driving conditions.<
2.Determine the combined weight of the
driver and passenger that will be riding in
your vehicle.
3.Subtract the combined weight of the driver
and passenger from XXX kilograms or
YYY pounds.
4.The resulting figure equals the available
amount of cargo and luggage load capacity.
For example, if the YYY amount equals
551 lbs and there will be two 150 lbs occu-
pants in your vehicle, the amount of avail-
able cargo and luggage load capacity is
251 lbs.
551 lbs minus 300 lbs = 251 lbs
5.Determine the combined weight of luggage
and cargo being loaded on the vehicle. That
weight may not safely exceed the available
cargo and luggage load capacity calculated
in step 4.

Wheels and tires
80
Wheels and tires
Tire inflation pressure
Information for your safety
It is not merely the tire's service life, but also
driving safety and driving comfort that largely
depend on the condition of the tires and the
maintenance of the specified tire pressure.
Check tire inflation pressures regularly
and correct them if necessary: at least
every two weeks and before every extended
journey. If you fail to observe this precaution
you may be driving on tires with incorrect tire
pressures, a condition that can not only com-
promise your vehicle's driving stability, but also
lead to tire damage and the risk of an accident.
Do not drive with deflated, i.e. flat tires, except
when using Run-Flat Tires. A flat tire will seri-
ously impair your vehicle's handling and braking
response. Attempts to drive on a flat tire can
lead to loss of control over the vehicle.<
Checking pressure
Check the tire inflation pressures only when the
tires are cold. This means after a maximum of
1.25 miles/2 km driving or when the vehicle has
been parked for at least 2 hours. Warm tires
have higher inflation pressures.
Inflation pressure specifications
The specified inflation pressures for your stan-
dard tires are provided on the placard on the
B-pillar and are visible when the driver's door is
open.Reinitialize the Flat Tire Monitor after cor-
recting the tire inflation pressure. Refer to
page51.<
The following tire inflation pressure tables show
the inflation pressures for the specified tire
sizes at ambient temperature.
The inflation pressures in the table apply
to BMW-approved tire sizes and recom-
mended tire brands. Your BMW Center will be
glad to supply this information.<
To determine the correct tire inflation pressure
for your tires, refer to the following tables.
Tire size
The inflation pressures in the table apply to
BMW-approved tire sizes and recommended
tire brands. Your BMW Center will be glad to
supply this information.

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Z4 Roadster 3.0i
Z4 Roadster 3.0si
Tire sizePressure specifications in psi/kPa
All pressure specifications in the table are
indicated in psi/kilopascal with cold tires,
cold = ambient temperature
225/50 R 16 92 V
225/45 R 17 91 W
205/55 R 16 91 H M+S
225/50 R 16 92 H M+S
225/45 R 17 91 H/V M+S30/210 35/240
Front: 225/45 R 17 91W
Rear: 255/40 R 17 94 W30/210
––
35/240
Front: 225/40 R 18 88 W
Rear: 255/35 R 18 90 W30/210
––
35/240
You will find more information about permissible loads and weights on page109.
Tire sizePressure specifications in psi/kPa
All pressure specifications in the table are
indicated in psi/kilopascal with cold tires,
cold = ambient temperature
225/45 R 17 91 W
225/45 R 17 91 H/V M+S33/230 38/260
Front: 225/45 R 17 91W
Rear: 255/40 R 17 94 W33/230
––
38/260
Front: 225/40 R 18 88 W
Rear: 255/35 R 18 90 W33/230
––
38/260
You will find more information about permissible loads and weights on page109.

Wheels and tires
82
Z4 Coupe 3.0si
Tire coding
Understanding the lettering on the tire sidewall
makes it easier to identify and choose the cor-
rect tires.
Tire size
Speed code letter
Q = up to 100mph or 160km/h
T = up to 118mph or 190km/h
H = up to 131mph or 210km/h
V = up to 150mph or 240km/h
W = up to 167mph or 270km/h
Y = up to 186mph or 300km/h
Tire Identification Number
Tires with DOT codes meet the guidelines of
the U.S. Department of Transportation.DOT code:
Tire age
The date on which the tire was manufactured is
indicated by the code on the sidewall:
DOT … 5005 indicates that the tire was manu-
factured in week 50 of the year 2005.
BMW recommends the replacement of all tires
every 6 years at the latest, even if a tire usage of
10 years is possible.
Uniform Tire Quality Grading
Quality grades can be found where applicable
on the tire sidewall between tread shoulder and
maximum section width. For example:
Treadwear 200 Traction AA
Temperature A
DOT Quality Grades
Tread wear
Traction AA A B C
Temperature A B C
Tire sizePressure specifications in psi/kPa
All pressure specifications in the table are
indicated in psi/kilopascal with cold tires,
cold = ambient temperature
225/45 R 17 91 W
225/45 R 17 91 H/V M+S33/230 39/270
Front: 225/45 R 17 91W
Rear: 255/40 R 17 94 W33/230
––
39/270
Front: 225/40 R 18 88 W
Rear: 255/35 R 18 90 W33/230
––
39/270
You will find more information about permissible loads and weights on page109.
e.g.
Nominal width in mm
Aspect ratio in Ξ
Radial belt construction
Rim diameter in inches
Load rating,
not on ZR tires
Speed code letter, in
front of the R on ZR tires225/50 R1692 V
e.g.
Manufacturer's code
for tire make
Tire size and
tire design
Tire ageDOT xxxx xxx 5005

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approved wheels and tires are used, BMW can-
not evaluate their suitability, and therefore can-
not be held liable for driving safety.<
You can inquire about the correct wheel/tire
combination at your BMW Center.
The correct combination of wheels and tires is
also necessary to ensure reliable operation of
various vehicle systems such as ABS and DSC.
To maintain good handling and vehicle
response, only use tires of a single brand and
tread configuration. After a tire has been dam-
aged, for instance, mount the original wheel and
tire combination again as soon as possible.
Recommended tire brands
Certain makes of tire are recommended by
BMW for each tire size. They are marked with a
clearly visible BMW designation on the sidewall
of the tire.
When properly used, these tires meet the high-
est standards in terms of safety and handling
characteristics.
Run-Flat Tires
When mounting new tires or changing over
from summer to winter tires and vice versa,
mount Run-Flat Tires for your own safety. In the
event of a flat, moreover, no spare wheel is
available. Your BMW Center will be glad to pro-
vide you with more information.
For safety reasons, BMW recommends
that damaged Run-Flat Tires be replaced
rather than repaired.<
Special characteristics of winter tires
BMW 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 summer tires, they
generally do not achieve the full performance of
winter tires.
Pay attention to speed
Always comply with the speed limit for the
winter tires mounted on your car; failure
to do so could result in tire damage and acci-
dents.<
If the car is capable of speeds higher than that
permitted for the winter tires, a label stating the
maximum permitted speed for the mounted
tires must be displayed in your field of view.
Specialist tire dealers and your BMW Center
can supply these labels.
Storage
Store tires in a cool, dry place, protecting them
against light whenever possible. Protect the
tires from contact with oil, grease and fuel. Do
not exceed the maximum tire inflation pressure
indicated on the sidewall of the tire.
Snow chains*
Only certain fine-link snow chains have been
tested by BMW, classified as safe for use and
recommended. Consult your BMW Center for
more information. Attach snow chains in pairs
and only to the rear wheels.
Observe the manufacturer's instructions when
mounting snow chains. Do not exceed a speed
of 30 mph/50 km/h when using snow chains.
You are not permitted to mount snow chains to
tires of the following sizes:
>255/40 R 17
>255/35 R 18
Do not initialize the Flat Tire Monitor if
snow chains are mounted, otherwise the
instrument might issue an incorrect reading.
When driving with snow chains, you may find it
helpful to activate DTC temporarily, refer to
page50.<