2004 BMW 745i tire pressure

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What you will need
1Screwdriver handle
2Emergency-release tool
30.4 in/10 mm open-end wrench
You will find the required tools in the
onboard tool kit mounted on the inside of
the luggage compartment lid, refer to
page 200.
Insert the emergency-release tool in the
screwdriver handle as shown in the illustra-
tion.
Releasing
1.Remove the floor mat and the cover on
the spare tire
2.Guide the emergency-release tool with
the screwdriver handle into the open-
ing, arrow 1
3.Apply the open-end wrench to the
hexagon on the emergency-release
tool.
Press against the resistance from the
spring to guide the emergency-release
tool all the way in, then hold it in place.
Turn the emergency-release tool in the
direction indicated by arrow 2, continu-
ing until you hear the mechanism snap
into place and feel resistance; maintain pressure on the tool after the mecha-
nism engages
4.Use the open-end wrench to turn the
emergency-release tool against the
drive unit's mechanical resistance, con-
tinuing to rotate it in arrow direction 2
until you feel a substantial increase in
turning effort
To prevent possible damage to the
rear brakes, always make sure that
the parking brake is completely released
before driving the vehicle.<
5.Return the tools to their places
6.Return the spare tire cover and the floor
mat to their original locations.
Have any defects repaired at the
nearest BMW center. The technicians
can also return the parking brake to normal
operational status after it has been
released manually in response to malfunc-
tion.<
Following manual release, the actual
status of the parking brake may vary
from that displayed by the indicator lamp.<
Operation after interruptions in
power supply
The parking brake may only be used
again, if it was released manually after
an interruption in power supply, i.e. as a
result of a discharged or disconnected bat-
tery. If this is not done, the parking brake
may fail to operate correctly. Even with the
parking brake engaged, there would be a
danger of the vehicle rolling on steep
hills.<
Once the electrical power supply has been
restored you can again use the parking
brake:
With the ignition on and the
vehicle stationary, briefly press
the button three times at inter-
vals of approx. 5 seconds. This
initializes the system as follows:
>Initializing the disengaged setting
>Engaging: the system registers the new
status and the brake setting is initial-

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Flat Tire Monitor
The concept
The Flat Tire Monitor keeps track of the
inflation pressures in the four fitted tires as
you drive. The system provides an alert
whenever the inflation pressure of one tire
drops significantly in relation to the pres-
sure of another tire.
The check of the tire inflation pressure is
based on monitoring the relative speeds of
the wheels. A flat tire is detected and
reported on the basis of a deviation in cer-
tain speed ratios.
Functional requirements
So that the Flat Tire Monitor can learn the
correct inflation pressure, please perform
the following:
1.Check the inflation pressures in all tires
2.Compare with the inflation pressure
table on page 189 and correct if neces-
sary
3.Initialize the system.
Limits of the system
The Flat Tire Monitor cannot indicate
sudden severe tire damage caused
by outside factors and does not detect a
natural, even pressure drop in all four
tires.<
In the following situations, on the other
hand, there can be delays in detecting tire
pressure losses, and even system failure:
>When you are driving on snow-covered
or slippery road surfaces
>In the case of performance-oriented
driving: slip on the drive wheels, high
lateral acceleration
>False alarms and undetected loss of
pressure may occur when you are driv-
ing with snow chains fitted.
Initializing the system
Perform the initialization immediately
after correcting the inflation pressure,
changing a tire or changing a wheel or all
wheels. A drive is necessary for this pur-
pose.<
1.Start the engine, but do not drive off
2.Select "FTM" from the "Settings" menu
and confirm. The initialization menu
appears
3.Select "SET" and confirm
4.Drive off.
Status: "FTM is being initialized" is dis-
played.
It takes at least 10 minutes before the Flat
Tire Monitor can detect and report a flat
tire.
When driving with snow chains, do
not initialize the system.<
Select and confirm to exit from the
menu.

Technology for comfort, convenience and safety
96
Flat tire
Indicator lamp
The symbol in the Info Display lights
up red and a message appears
simultaneously. In addition, an
acoustic signal sounds.
Please note any supplementary information
that appears on the Control Display. You
can find more information on the Check
Control starting at page 82.
1.Reduce speed and stop the vehicle
carefully. Avoid sudden braking and
steering maneuvers
2.Identify damaged tire
If identification is not possible,
contact your BMW center.<
3.Replace the damaged tire, refer to
Changing wheels on page 202.
Vehicles with run-flat tires:
1.Cautiously reduce the vehicle speed to
below 50 mph/80 km/h. Avoid sudden
braking and steering maneuvers. Do
not exceed a vehicle speed of 50 mph/
80 km/h
Due to the reinforcement on the
side walls of the run-flat tires,
inflation pressure loss can not usually
be recognized from the outside, refer to
Run-flat tires on page 205.<
2.To continue driving, comply with the
instructions for driving with damaged
tires on page 205.
System malfunctions
Indicator lamp
The symbol in the Info Display lights
up yellow and a message appears
simultaneously. Please contact
your BMW center for assistance.
Please note any supplementary information
that appears on the Control Display.
Self-leveling suspension*
In the event of malfunction
A Check Control message appear-
ing together with this symbol indi-
cates a malfunction in the self-lev-
eling suspension. Please take note of the
additional information on the Control Dis-
play.
Stop and inspect the vehicle. If the rear of
the vehicle is visibly lower than the front,
possibly accompanied by a tilt noticeable
when you compare the left rear with the
right rear, please respond by immediately
proceeding to the nearest BMW center.
Drive with appropriate caution in the mean-
time. The vehicle has reduced ground
clearance and driving comfort may be
noticeably reduced. Even if the attitude of
the vehicle is normal, you should consult
the nearest BMW center if the warning
lamp indicates a system fault.
Brake force display
The Brake force display indicates the inten-
sity with which you are applying your
brakes to drivers of following vehicles.
The display consists of two stages:
>Normal braking:
The brake lamps in the tail lamp assem-
blies and the high-mount brake lamp on
the rear tray light up during braking
>Heavy braking and braking with ABS:
The tail lamps also light up with the
same intensity as the standard brake
lamp units to enhance the warning
effect of the brake lamps.

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to as hydroplaning, and is characterized
by a partial or complete loss of contact
between tires and road surface, ultimately
undermining your ability to steer and brake
the vehicle.<
Driving through water
Do not drive through water on the
road if it is deeper than 1 ft/30 cm,
and then only at walking speed at the most.
Otherwise, the vehicle's engine, the electri-
cal systems and the transmission may be
damaged.<
Brake system
Braking with ABS
The best way to achieve the best response
from the ABS is to apply maximum pres-
sure to the brake pedal Ð panic stop. Since
the vehicle maintains steering responsive-
ness, you can nevertheless avoid possible
obstacles with a minimum of steering
effort.
Pulsation at the brake pedal combines with
sounds from the hydraulic circuits to indi-
cate to the driver that ABS is in its active
mode.
Do not drive with your foot resting on
the brake pedal. Otherwise, even light
but consistent pedal pressure can lead to
high temperatures, brake wear and possi-
bly even brake failure.<
Disc brakes
Driving in wet conditions
While driving in wet conditions and in
heavy rain, it is a good idea to apply light
pressure to the brake pedal every few
miles. Monitor 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 to
ensure that full braking efficiency will then
be available when you need it.
Hills
You can retain full and unimpaired braking
efficiency by downshifting to a gear in
which only minimal brake applications are
needed when descending long or steep
downhill stretches.
You can further enhance the engine's
braking effect by selecting a lower gear
in the automatic transmission's manual
mode, downshifting as far as first gear
on extremely steep stretches, refer to
page 67. This strategy helps you avoid
placing excessive loads on the brake sys-
tem.
Never allow the vehicle to coast with
the transmission in Neutral Ð or with
the engine switched off Ð as there is no
engine braking when the transmission is in
Neutral, and no power-assist for brakes
and steering when the engine is not run-
ning.
Never allow floor mats, carpets or any other
objects to protrude into the area around the
accelerator and brake pedals and obstruct
their movement.<
Corrosion
When the vehicle is driven only occasion-
ally, during extended periods when the
vehicle is not used at all, and in operating
conditions where brake applications are
less frequent, there is an increased ten-
dency for corrosion to form on rotors, while
contaminants accumulate on the brake
pads. This occurs because the minimal
pressure which must be exerted by the
pads during brake applications to clean the
rotors is not reached.
Should corrosion form on the brake rotors,
the brakes will tend to respond with a pul-
sating effect that even extended applica-
tion will fail to cure.
Brake pads
If the brake pad wear warning lamp
appears in the Check Control,
accompanied by a text. Please take
careful note of the additional information on
the Control Display.

Wheels and tires
188
Wheels and tires
Tire inflation pressure
Information for your safety
It is not merely the tire's service life, but
also driving comfort and Ð to a great extent
Ð driving safety that depend on the condi-
tion of the tires and the maintenance of the
specified tire pressure.
Check the tire inflation pressure regu-
larly and correct it if necessary,
including the spare wheel: at least every
two weeks and before beginning a longer
trip. If you fail to observe this precaution
you may be driving on tires with incorrect
tire pressures, a condition that can not only
compromise your vehicle's stability, but
also lead to tire damage and the risk of an
accident.
Do not drive with deflated, i.e. flat tires,
except run-flat tires. A flat tire will seriously
impair your vehicle's handling and braking
response. Attempts to drive on a flat tire
can lead to loss of control over the vehi-
cle.<
Checking inflation pressure
Only check tire inflation pressure when
the tires are cold. i.e. after a maximum of
2 hours' driving or when the vehicle has
been parked for at least 2 hours. When tires
are warm, the tire inflation pressure
increases.
After correcting the inflation pressure(s),
always reinitialize the Flat Tire Monitor,
refer to page 95.
Inflation pressure for original tires
The inflation pressures for your standard
tires can be found on the door pillar when
you open the driver's door.
Inflation pressure for other tire sizes
The table below provides all the correct
inflation pressures for the specified tire
sizes at ambient temperature.
For correct identification of the right
tire inflation pressure for your tires,
observe the specifications for the corre-
sponding tire size.<

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745i, 745Li
760Li
Tire sizePressure specifications in psi/kPa
All pressure specifications
in the table are indicated in
psi/kilopascal with cold tires.
Cold = ambient temperature
245/50 R 18 100 V M+S
245/55 R 17 102 W
245/50 R 18 100 W
245/55 R 17 102 Q M+S
245/50 R 18 100 Q M+S32/220 35/240 35/240 42/290
Front: 245/45 R 19 98 W 32/220 - 35/240 -
Rear: 275/40 R 19 101 W - 35/240 - 42/290
Front: 245/40 R 20 95 Y 32/220 - 35/240
Rear: 275/35 R 20 98 Y - 35/240 - 42/290
More details on the permitted load and weights can be found on page 214.
Tire sizePressure specifications in psi/kPa
All pressure specifications
in the table are indicated in
psi/kilopascal with cold tires.
Cold = ambient temperature
245/50 R 18 100 V M+S
245/50 R 18 100 W
245/50 R 18 100 Q M+S35/240 38/260 38/260 42/290
Front: 245/45 R 19 98 Y 35/240 - 38/260 -
Rear: 275/40 R 19 101 Y - 38/260 - 42/290
Front: 245/40 R 20 95 Y 35/240 - 38/260
Rear: 275/35 R 20 98 Y - 38/260 - 42/290
More details on the permitted load and weights can be found on page 214.

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Temperature
The temperature grades are A Ð the
highest Ð, B, and C, representing the tire's
resistance to the generation of heat and its
ability to dissipate heat when tested under
controlled conditions 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 car tires must meet
under the Federal Motor Vehicle Safety
Standard No. 109. Grades B and A repre-
sent 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, underinflation, or excessive load-
ing, either separately or in combination,
can cause heat buildup and possible tire
failure.<
Run-flat tires
You will recognize run-flat tires by a circular
symbol containing the letters RSC on the
side of the tire, refer to page 193.
M+S
Winter and all-season tires.
These have better winter properties than
summer tires.
Tire condition
Inspect your tires frequently for tread wear,
signs of damage and for foreign objects
lodged in the tread. Check the tread depth.
Tire tread
The tread depth should not fall below e in/
3 mm.
At tread depths below e in/3 mm, there is
an increased risk of high-speed hydroplan-
ing, even when only small amounts of
water are present on the road surface.As winter tires display a noticeable loss in
their ability to cope with cold-weather driv-
ing conditions once the tread wears to
below k/K in/4 mm, to ensure continued
safety you should always have such tires
replaced.
Wear indicators at the tread-groove base,
refer to arrow, are distributed over the tire's
circumference and are marked on the side
of the tire with TWI Ð Tread Wear Indicator.
These indicators signal at a tread depth
of k/FK in/1.6 mm that the legally permitted
wear limit has been reached.
Tire damage
Unusual vibrations encountered dur-
ing normal vehicle operation can
indicate tire failure or some other vehicle
defect. This can, for example, be caused
by driving over curbs.
These kinds of problems may also be
signaled by other changes in vehicle
response, such as a strong tendency to
pull to the left or right. Should this occur,
respond by immediately reducing your
speed. Carefully proceed Ð or have your
vehicle towed Ð to the nearest BMW center
or tire dealer to have the wheels or tires
inspected.
Tire damage, extending to sudden and
complete loss of pressure in extreme
cases, can pose a potentially lethal safety
hazard for the vehicle's occupants and
other road users alike.<

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Storage
Always store wheels and tires in a cool, dry
place with as little exposure to light as pos-
sible. Always protect tires against all con-
tact with oil, grease and fuels.
Do not exceed the maximum tire inflation
pressure indicated on the side wall of the
tire.
Run-flat tires*
You will recognize run-flat tires by a circular
symbol containing the letters RSC on the
side of the tire. They consist of self-con-
tained tires and special rims. The tire rein-
forcement ensures that the tire retains
some residual safety in the event of pres-
sure drop and driving remains possible to
a restricted degree.
If you switch from summer to winter
tires, or vice versa, use run-flat tires,
as in the event of a breakdown there is no
spare wheel available. In this case, BMW
recommends that you consult your BMW
center. Your BMW center is qualified to
handle run-flat tires and equipped with the
necessary special tools.<
Continuing driving with a damaged
tire
Driving on run-flat tires can continue,
depending on the vehicle load and the
severity of the tire damage, at a maximum
speed of 50 mph/80 km/h.
In the case of complete inflation pressure
loss, 0 psi/kPa, or obvious tire damage,
you can estimate the possible distance for continued driving on the basis of the fol-
lowing guide values:
>With low load:
1 to 2 persons without luggage:
Approx. 150 miles/250 km
>With medium load:
2 persons, luggage compartment full, or
4 persons without luggage:
Approx. 90 miles/150 km
>With full load:
More than 4 persons, luggage compart-
ment full:
Approx. 30 miles/50 km.
Drive reservedly and do not exceed
a speed of 50 mph/80 km/h. With
inflation pressure loss, the driving charac-
teristics change, for example reduced track
stability on braking, extended braking dis-
tance, and altered self-steering character-
istics.<
Snow chains*
BMW only tests certain snow chains, clas-
sifies them as road-safe and approves
them. Consult your BMW center for more
information. BMW recommends only using
these approved, narrow-link snow chains.
These snow chains are approved exclu-
sively for use in pairs on the rear wheels,
and should only be mounted on tires
with the dimensions 245/50 R 18. Observe
the manufacturer's instructions when
installing snow chains.Do not exceed a
vehicle speed of 30 mph/50 km/h with the
chains mounted.
After mounting snow chains, do not
activate the Flat Tire Monitor.
When you are driving with snow chains, it
can be beneficial to switch off DSC briefly,
refer to page 93.<