BMW 320i 2003 Owners Manual

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OverviewControlsMaintenanceRepairsDataIndex

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113
Overview
Controls and features
Operation, maintenance
Owner service procedures
Technical data
Index
OverviewControlsMaintenanceRepairsDataIndex

114Special operating instructions
Break-in proceduresTo ensure that your vehicle continues to
provide maximum economy throughout
an extended service life, we request
that you devote careful attention to the
following instructions.Engine and differentialThe first 1,250 miles/2,000 km:
Attempt to constantly vary both vehicle
and engine speeds during these initial
miles while remembering to avoid
engine speeds in excess of 4,500 rpm
and/or vehicle speeds of over
100 mph / 160 km/h:
Always obey all official speed limits.
Refrain from using full throttle and avoid
pressing the accelerator beyond the
kickdown point.
You can then proceed to increase both
engine and vehicle speeds once the ini-
tial 1,250 miles/2,000 km have elapsed.
Please remember to observe these
same break-in procedures if either the
engine or the differential should have to
be replaced later in the course of the
vehicle's service life.
TiresOwing to technical factors associated
with their manufacture, tires do not
achieve their full traction potential until
an initial break-in period has elapsed.
We thus ask you to drive with extra care
during the first 200 miles/300 km.
Always obey all official speed limits.
When the vehicle is operated on
wet or slushy roads, a wedge of
water may form between the tire and
the road surface. This phenomenon is
referred to as hydroplaning and can
lead to partial or complete loss of trac-
tion, vehicle control and braking effec-
tiveness. Reduce your speed on wet
roads. before the brake pads and rotors
achieve the optimal pad-surface and
wear patterns required for trouble-free
operation and an extended service life
later on.
To break in the separate parking brake
drums, apply the parking brake lightly
when coasting to a standstill – at a traf-
fic signal, for instance; use caution to
avoid posing a danger to other road
users.
You can prevent corrosion in the drums
by periodically repeating this proce-
dure.
The brake lamps do not come on
when the parking brake is set.
Vacuum for the brake system servo unit
on your BMW is available only when the
engine is running. When you move the
vehicle with the engine off – when tow-
ing, for example – substantially higher
levels of pedal force will be required to
brake the vehicle. before the clutch starts to operate at
optimum efficiency. Remember to
engage the clutch carefully during this
initial period.

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.
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Brake systemBrake fluid levelIf the brake fluid level is too low and
brake pedal travel has become longer,
there may be a defect in one of the
brake system's hydraulic circuits.
Proceed to the nearest BMW cen-
ter. It may be necessary to apply
higher levels of pressure to the pedal
when stopping and braking distances
may also be longer. Please remember
to adapt your driving style accord-
ingly. with the vehicle parked or in storage,
and operating conditions in which brak-
ing is restricted to gentle, low-pressure
applications will all increase the ten-
dency for corrosion to form on the
rotors; this is often accompanied by a
simultaneous accumulation of contami-
nation on the brake pads. The pads
must exert a certain minimal level of
pressure against the rotors for the disc
brakes' inherent self-cleaning effect to
remain effective; the pressure available
under the above conditions may not
provide adequate cleansing.
If the brake rotors are corroded, they
will tend to respond to braking with a
pulsating effect that even extended
brake applications will fail to cure.
When driving in heavy rain and on wet
roads 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
pose a hazard to you or to other road
users. The heat generated in this pro-
cess helps dry the pads and rotors to
ensure that your brake system will
respond with undiminished efficiency
when you need it.
When descending steep hills and
extended grades, downshift to a gear
that will allow you to continue safely
with only a minimal amount of braking.
By minimizing the loads placed on the
brake system, this strategy helps
ensure that optimal brake system
response will remain available at all
times. Use care to avoid exceeding the
approved engine-speed range, refer to
page 71.
Do not coast with the clutch
depressed or with the transmis-
sion or selector lever in Neutral. Do not
coast with the engine shut off. The
engine provides no braking effect when
the clutch is depressed and there is no
power-assist for braking or steering
when the engine is not running.
BMW 325xi, 330xi: always refer all
brake inspection and service work to
your BMW center, as failure to observe
the special procedures could result in
damage to components of the all-wheel
drive.
Never allow floor mats, carpets or any
other objects to protrude into the area
around the accelerator, clutch and
brake pedals and obstruct their move-
ment. For your own safety: use only
brake pads that BMW has
released for your particular vehicle
model. BMW cannot evaluate non-
approved brake pads to determine if
they are suitable for use, and therefore
cannot ensure the operating safety of
the vehicle if they are installed.<

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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118
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 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.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. 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.
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.
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
Tire condition

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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120
Wheel and tire combinationsThe right choice
BMW recommends using only
wheels and tires that have been
approved by BMW for use on your par-
ticular model. Although other wheels
and tires may theoretically have the
same dimensions, variations in factors
such as manufacturing tolerances can
result in contact between tire and body-
work, ultimately leading to serious acci-
dents. 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 various systems such
as ABS, ASC+T/DSC and ADB/
ADB-X/DBC. The function of these sys-
tems is impaired if improper wheel-tire
combinations are used.
For this reason, use only tires of the
same manufacture and tread configura-
tion. In the event of a flat tire, for exam-
ple, remount the approved wheel and
tire combination as soon as possible.<
StorageStore tires in a cool, dry place, protect-
ing them against light whenever possi-
ble. Protect the tires against contact
with oil, grease and fuel.
Winter tiresChoosing the right tireBMW recommends winter tires – M+S
tires – for operation under inclement
winter driving conditions. While all-sea-
son tires – M+S designation – provide
better winter traction than the corre-
sponding summer tires, they generally
do not achieve the performance of win-
ter 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.<