2003 BMW 325xi SEDAN tire pressure

85
Tire Pressure Monitor (TPM)*The conceptTPM monitors the tire pressures at all
four tires even while the vehicle is mov-
ing. The system provides an alert when-
ever the inflation pressure drops signifi-
cantly below the specified pressure in
one or more tires.
This indicator lamp in the instru-
ment cluster informs you when
the tire pressure deviates from
the target values.
Initializing the systemInitializing is necessary to familiarize the
system with the correct inflation pres-
sures.
Repeat this process after tire replace-
ment, tire rotation or any changes in tire
inflation pressure.
1. Check the tire inflation pressures in
all the tires, comparing them with the
inflation pressure chart on page 25
and adjusting their pressure if neces-
sary
2. Turn ignition key to position 2, do not
start the engine
3. Press the button long enough for the
yellow indicator lamp in the instru-
ment cluster to light up for a few sec-
onds
4. After a few minutes' driving time,
TPM sets the current inflation pres-
sures in the tires as the target values
to be monitored.In the event of loss in inflation
pressureIf the inflation pressure has dropped
significantly over a long period of time,
which is normal for any tire, the yellow
indicator lamp will come on.
This alerts you to have the tires inflated
to the specified pressures as soon as
possible.
If you are prompted to check the
tire pressure shortly after a cor-
rection has been made, this indicates
that the corrected values were not
valid. Please check the inflation pres-
sure again and make corrections
according to the inflation pressure
table. Then reinitialize the system. sure, a red light will appear in the indi-
cator lamp. This visual alert is accom-
panied by an acoustic warning signal.
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86
If this occurs, reduce vehicle speed
immediately and stop the vehicle in a
safe location. Avoid hard brake applica-
tions. Do not oversteer. Replace the
defective tire, refer to page 141.
The space-saver spare tire is pro-
vided for temporary use only in the
case of a tire failure. It does not have
TPM electronics and is not monitored.
The spare tire that has the same dimen-
sions as the tires already mounted on
the vehicle is equipped with the neces-
sary TPM electronics and will also be
monitored once the tire has been
mounted and the system initialized.<
The TPM cannot alert you to
severe and sudden tire damage
caused by external factors.<
Have the tires changed by your
BMW center.
Your BMW center has the information
needed for working with TPM and is
equipped with the necessary special
tools. quency can interfere with TPM.
The yellow indicator lamp will come on
during the malfunction.
The indicator lamp also comes on
>in the event of a system fault
>if a wheel is mounted without the
appropriate electronics
>if, in addition to the spare tire, addi-
tional wheels with TPM electronics
are on board.
Please refer the problem to your BMW
center.
Flat Tire Monitor*The conceptAs you drive, the Flat Tire Monitor
keeps track of pressure levels in all four
tires in order to detect and warn of any
substantial pressure loss.
The system actually detects pressure
loss by monitoring differences in the
relative speeds of the four wheels. It
interprets variations outside specified
limits as severe pressure loss, and then
responds by generating a warning.
Tire Pressure Monitor (TPM)*

87
Initializing the systemInitializing is necessary to familiarize the
system with the correct inflation pres-
sure.
Repeat this process after any changes
in tire inflation pressure, tire rotation or
replacement. Do not carry out further
system initialization after adjusting the
inflation pressure and letting the system
"learn" the correct pressures.
1. Check the tire inflation pressures in
all the tires, comparing them with the
inflation pressure chart on page 25
and adjusting their pressure if neces-
sary
2. Turn the ignition key to position 2
3. Press button as long as you need to
until the indicator lamp in the instru-
ment cluster lights up. After a little
while, the indicator lamp will go out
by itself
4. After a few minutes' driving time, the
Flat Tire Monitor adopts the current
pressure levels as the reference, and
from that point on, can detect and
report a flat tire.
To activate/deactivate the systemThe Flat Tire Monitor automatically
assumes operation whenever you turn
the ignition key to position 2. Unless
manually deactivated, it is always on
during normal vehicle operation.
To deactivate the system: press the
button, the yellow indicator lamp comes
on.
To activate the system: press the but-
ton again, the indicator lamp goes out.
You should deactivate the system
before driving with snow chains, as the
chains can generate spurious warnings
and/or prevent the system from detect-
ing actual pressure loss.
Flat Tire Monitor*
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88
Flat tire
The red warning lamp in the
instrument cluster lights up to
warn of pressure loss and tire
failure. This visual alert is accompanied
by an acoustic warning signal. Reduce
your speed immediately, and steer and
brake gently as you bring the vehicle to
a stop.
To reset the warning lamp: after replac-
ing the damaged tire you will need to
reset the red warning lamp manually:
maintain pressure on the Flat Tire Moni-
tor button until the warning lamp goes
out. Then reinitialize the system.
The Flat Tire Monitor cannot pro-
vide you with advance warning of
sudden and severe tire damage caused
by external factors.
The system also does not detect the
gradual and minor loss of pressure that
all tires display over extended periods
of time.<
Check tire inflation pressures on a
regular basis, correcting them as
necessary; refer to page 25.
The system may respond to operation
on slippery or snow-covered road sur-
faces with false warnings or delays in
detecting actual pressure loss.
Performance-oriented driving – slip at
the drive wheels, high rates of lateral
acceleration – can also increase the
time that the Flat Tire Monitor requires
to detect a flat.<
System malfunctionsThe yellow indicator lamp in the instru-
ment cluster lights up and remains on
until the problem is corrected.
Please refer the problem to your BMW
center.
Flat Tire Monitor*

115
Driving notes
Brakes: do not drive with your foot
resting on the brake pedal. Even
light but consistent pedal pressure can
lead to high temperatures, brake wear
and possibly even brake failure.
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 phenomenon can lead to partial or
complete loss of contact between the
tires and road surface, as well as loss of
vehicle control and braking ability.
Driving through water: do not drive
through water on the road if it is deeper
than 1 ft/30 cm, and then only at walk-
ing speed. Otherwise, the vehicle's
engine, the electrical systems and the
transmission may be damaged.
Rear tray: never use it to store heavy or
hard objects, as otherwise occupants
could be injured during braking maneu-
vers.
Clothes hooks: when hanging clothing
from the hooks, be sure that they will
not obstruct the driver's vision. Do not
hang heavy objects on the hooks. If you
do so, they could cause personal injury
during braking or evasive maneuvers.<
Antilock Brake System (ABS)The conceptABS keeps the wheels from locking
during braking, thereby enhancing
active driving safety.Braking with ABSIf you are in a situation that requires full
braking, you will exploit the full benefits
of the ABS system if you apply maxi-
mum pedal 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.
Pulsation at the brake pedal combined
with sounds from the hydraulic circuits
indicates to the driver that ABS is in its
active mode.Dynamic Brake Control (DBC)DBC is included in the DSC, refer to
page 80.
The system responds to sudden, high-
intensity applications of force to the
brake pedal by automatically braking
the vehicle with maximum boost to
achieve the shortest possible braking
distances during "panic stops". This
system exploits all the benefits of ABS.Do not reduce the pressure exerted
against the brake pedal until the brak-
ing maneuver has been completed.
DBC is deactivated when you release
the brake pedal.
Cornering Brake Control (CBC)CBC is an advanced engineering devel-
opment of ABS. When braking during
cornering with high lateral accelera-
tion, or when braking during a lane
change, vehicle stability is improved
and the steering response is enhanced.
OverviewControlsMaintenanceRepairsDataIndex

117 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 inflation pressure.
Incorrect tire inflation pressure is a fre-
quent cause of tire damage. Tire pres-
sure also has a major effect on your
BMW's handling response.
Be sure to check the tire inflation
pressure, including the pressure
of the space-saver spare tire or the
spare tire, on a regular basis, at least
twice a month and before every
extended journey, refer to page 25.
Otherwise, incorrect tire pressure can
lead to poor handling, to tire damage
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 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 vehi-
cle so that the permitted load on the
tires is not exceeded. Overloading can
lead to overheating and internal tire
damage.
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. This type of problem can be
caused by contact with curbs, etc. This
is also true for irregularities in the vehi-
cle's handling characteristics, such as a
pronounced tendency to pull to the left
or right. Should this occur, respond by
immediately reducing your speed. Pro-
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119
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, underinflation, 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:
Tread wear 200
Traction AA
Temperature A
BMW advises against using
retreaded tires, since driving
safety may be impaired. This is due to
the possible variations in casing struc-
tures and, in some cases, to their
extreme age, which can lead to a
decrease in their durability.<
Tire ageThe date on which the tire was manu-
factured is indicated by the code on the
sidewall:
DOT... 3502 indicates that the tire was
manufactured in week 35 of the year
2002.
BMW recommends the replacement of
all tires – including the spare tire* –
when the tires are no more than 6 years
old, even if a tire life of 10 years is pos-
sible.Run Flat tires*Run Flat tires consist of self-supporting
tires and special rims. The tire rein-
forcement ensures that the tire retains
some residual safety in the event of
pressure drop and driving remains pos-
sible to a restricted degree. The vehicle
is equipped with a Tire Pressure Moni-
tor (TPM) or Flat Tire Monitor, which
indicate a flat tire.
For additional information on the Tire
Pressure Monitor (TPM) or Flat Tire
Monitor, refer to page 85 or 86.
Run Flat tires are only possible in
conjunction with the Tire Pres-
sure Monitor (TPM) or Flat Tire Moni-
tor.<
Tire replacement
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121
Tire condition, tire pressureAt tread depths below approx. 3/16 in /
4 mm, winter tires display a perceptible
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 — 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 any
BMW center for details. BMW recom-
mends using only these approved fine-
link snow chains. Use them in pairs on
either summer or winter tires, but only
on both rear wheels.
BMW 325xi, 330xi: only in an emer-
gency – for instance, with the vehicle
stuck on one side, or when obstruc-
tions make it impossible to reach one
tire – a chain may also be mounted on
just one tire for the limited period
needed to resolve the problem.
Comply with all manufacturer's safety
precautions when mounting the chains.
Do not exceed a speed of 30 mph /
50 km/h when using snow chains.You cannot mount snow chains on the
following tires:
225/50 R 16
225/45 R 17
225/40 R 18
245/40 R 17
255/35 R 18Winter tires
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