91
Flat Tire Monitor*The conceptAs you drive, the Flat Tire Monitor
keeps track of pressure levels in all four
tires. The system alerts you whenever
the inflation pressure of a tire falls sig-
nificantly below the pressure of another
tire.
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.Functional requirementsIn order for the Flat Tire Monitor to learn
the correct tire inflation pressure,
please do the following:
1. Check the tire inflation pressures in
all tires
2. Compare them with the tire inflation
pressure table on page 26 and cor-
rect them, if necessary
3. Initialize the system.
System limitations
The Flat Tire Monitor cannot pro-
vide you with advance warning of
sudden and severe tire damage caused
by external factors and does not detect
the balanced and very gradual pressure
loss that takes place in all four tires
over an extended period of time.<
On the other hand, the following situa-
tions can lead to a delayed detection of
pressure loss and even to the system
not functioning:
>Driving on snow-covered or slippery
roads
>Performance-oriented driving: slip at
the drive wheels, high levels of lateral
acceleration
>When driving with snow chains, false
warnings and undetected pressure
losses may occur
>When driving with a space-saver
spare tire, the Flat Tire Monitor can-
not function.
Initializing the system
Each time you correct the pres-
sure in a tire, or change a wheel or
tire, reinitialize the system immediately
afterwards. This requires a bit of driv-
ing.<
1. Before driving off, start the engine
but do not start driving
2. Press the button as long as you need
to until the yellow indicator lamp in
the instrument cluster lights up for a
few seconds
3. Drive off.
It takes a few minutes before the Flat
Tire Monitor can detect a flat tire and
issue a warning.
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92
When driving with snow chains or
a space-saver spare tire, do not
initialize the system.<
Flat tire
The indicator lamp in the instru-
ment cluster lights up red. This
visual alert is accompanied by
an acoustic warning signal.
1. Carefully reduce speed and come to
a stop. Avoid sudden braking and
steering maneuvers
2. Determine which wheel is damaged
If this cannot be determined, con-
tact your BMW center.<
3. Replace the damaged wheel, refer to
Changing a wheel on page 147.
After replacing the damaged tire, initial-
ize the system.
Vehicles with Run Flat tires:
1. Carefully reduce your speed to under
50 mph / 80 km/h. Avoid strong
braking and steering maneuvers. Do
not exceed a speed of 50 mph /
80 km/h.
Because the sides of Run Flat
tires are reinforced, a drop in infla-
tion pressure usually cannot be
detected from the outside, refer to Run
Flat tires, page 150.<
2. To continue driving, follow the
instructions under Driving with a
damaged tire on page 151.
System malfunction
The indicator lamp in the instru-
ment cluster lights up yellow.
The Flat Tire Monitor is malfunc-
tioning or out of order. Please refer the
problem to your BMW center.
Brake force displayThe brake force display indicates to the
driver of the vehicle behind you how
hard you are braking your vehicle.
The display has two levels:
>Normal braking: the brake lamps
among the rear lamps and the center
brake lamp light up
>Hard braking or use of ABS: the tail
lamps light up with the same bright-
ness as the brake lamps and thereby
intensify the visual effect of the brake
lamps.
Flat Tire Monitor*
124Wheels 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. It also sig-
nificantly influences the roadholding
ability of your BMW.
Be sure to check the tire inflation
pressure, including 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. If this is not done,
incorrect tire pressures can cause driv-
ing instability and tire damage, ulti-
mately 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 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 – see arrow
– are embedded in the base of the tire's
tread. Their locations are indicated by
the letters TWI – Tread Wear Indicator –
at various points on the tire's shoulder.
When the tread reaches a depth of
1/16 in / 1.6 mm, these indicators
appear and signal that the tires have
worn to the minimum legal level.
125
Do not drive on a deflated – flat –
tire unless your vehicle is
equipped with Run Flat tires. 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.
The ultimate result can assume the
form of a sudden air loss.
Unusual vibrations encountered during
normal vehicle operation can indicate a
damaged tire or some other vehicle
malfunction. This type of problem can
be caused by contact with curbs, etc.
This is also true for irregularities in the
vehicle's handling characteristics, such
as a pronounced tendency to pull to the
left or right. Should this occur, respond
by immediately reducing your speed.
Proceed carefully to the nearest BMW
center 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 sud-
den and complete air loss, can endan-
ger the lives of both the vehicle occu-
pants and other road users.<
Tire replacementTo maintain good handling and vehicle
response, use only tires of a single
tread configuration from a single manu-
facturer.
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 gradesTread wear
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.
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.
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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126
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, underinflation, or
excessive loading, either separately or
in combination, can cause heat buildup
and possible tire failure.
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... 3603 indicates that the tire was
manufactured in week 36 of the year
2003.
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*Before purchasing tires, check if your
BMW is equipped with Run Flat tires.
These are indicated by a circular sym-
bol containing the letters RSC on the
tire sidewall, refer to Changing a wheel.
In this case, use only Run Flat tires,
since no spare wheel is available in the
event of a flat. For more information on
Run Flat tires, refer to page 150.
Run Flat tires are available only in
combination with the Flat Tire
Monitor.<
Tire replacement
127
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. BMW cannot evaluate all tires
and wheels on the market, and is thus
unable to guarantee that the vehicle will
continue to perform safely if unap-
proved tires and/or wheels are
mounted.<
For each tire size, BMW has assessed
the safe performance of specific tire
brands and approved them for use.
Consult any BMW center for details.
Comply with any local/national regula-
tions, for example by recording the tire
type in the vehicle documents.
The correct wheel-tire combina-
tion affects different systems such
as ABS, DSC and ADB-X/DBC. The
function of these systems is impaired if
improper wheel-tire combinations are
used. For this reason, use only tires of
the same manufacture and tread con-
figuration. In the event of a flat tire, for
example, remount the approved wheel
and tire combination as soon as possi-
ble.<
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.
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 winter tires
made by the same manufacturer and
having the same tread configuration on
all four wheels.
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 trained
professionals only. Any BMW center
has the required technical knowledge
and the proper equipment and will be
happy to assist you.
tires. These are indicated by a circular
symbol containing the letters RSC on
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128
the tire sidewall, refer to Changing a
wheel. In this case, use only Run Flat
winter tires, since no spare tire is pro-
vided in the event of a flat tire.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.325xi: in an extreme emergency – for
instance, with the vehicle stuck on one
side, or when obstructions 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
245/40 R 17
225/40 R 18
255/35 R 18
Do not initialize the Flat Tire Moni-
tor after mounting snow chains to
the tires.
When driving with snow chains, it may
be useful to turn off the DSC for a short
time, refer to page 87 or 88.
147
Tailgate lamp5 watt bulb
1. Pull out the bulb socket
2. Replace the bulb.
Changing a wheel
Safety precautions in the event of
a flat tire or wheel change:
Stop the vehicle as far as possible from
passing traffic. Park on a firm, flat, sur-
face. Switch on the hazard warning
flashers. Turn the steering wheel to the
straight-ahead position and engage the
steering lock. Shift into 1st or Reverse,
or if you have an automatic transmis-
sion position the selector lever in Park,
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 a warning triangle or portable hazard
warning lamp is available, set it up on
the roadside at an appropriate distance
from the rear of the vehicle. Comply
with all local safety guidelines and reg-
ulations.
Change the wheel only on a level, firm
surface which is not slippery. Avoid
jacking the vehicle on a soft or slippery
support surface – snow, ice, loose
gravel, etc. – as either the vehicle or the
jack could slip sideways.
Position the jack on a firm support sur-
face.
Do not place wooden blocks or similar
objects under the jack. They could pre-
vent the jack from extending to its full
height and reduce its support capacity.
Do not lie under the vehicle or start the
engine when the vehicle is supported
by the jack. There is otherwise a risk of
fatal injury.<
Your BMW is equipped with a spare tire
or a space-saver spare tire designed for
temporary use in maintaining the vehi-
cle's mobility in an emergency.
To remove the spare tire, lift the
floor panel in the cargo area com-
pletely out, refer to page 113.<
Lamps and bulbs
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