2004 BMW 325I SEDAN wheel

87
Dynamic Stability Control (DSC)The conceptDSC maintains vehicle stability, even in
critical driving situations.
The DSC is operational every time you
start the engine.
DSC incorporates the Dynamic Traction
Control (DTC) and Cornering Brake
Control (CBC) functions.
For information on vehicles with all-
wheel drive, refer to page 89 ff.Indicator lamps
The indicator lamp in the instru-
ment cluster goes out shortly
after the ignition has been
switched on; refer to page 19.
>The indicator lamp flashes: DSC is
actively controlling drive torque and
braking intervention
>The indicator lamp stays lit: DSC has
been switched off with the button;
DTC and DBC are operational. DTC
control intervention is not indicated.
The indicator lamp and the
brake warning lamp continu-
ously light up in yellow:
The DSC, DTC and DBC have
been switched off manually or
there is a system malfunction.
The vehicle will remain completely
operational, however, without DSC. In
the event of a fault, please consult your
BMW center.
Indicator and warning lamps for
Canadian models.
Deactivating the DSC/activating
the DTCPress the DSC button briefly; the indi-
cator lamp comes on and stays on.
DSC is deactivated; DTC is operational.
In the following rare situations, it may
prove useful to activate the DTC for a
brief period:
>When rocking the vehicle or starting
off in deep snow or on loose surfaces
>When driving on snow-covered
grades, in deep snow, or on a snow-
covered surface that has been
packed down from being driven on
>When driving with snow chains.
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91
Hill Descent Control (HDC)*The conceptBy reducing the vehicle's speed on
steep downhill stretches, HDC main-
tains predictable vehicle handling
response to provide you with control of
your BMW during extreme descents.
The vehicle slows to a pace just slightly
faster than walking speed.
HDC is available for activation at vehi-
cle speeds below approx. 22 mph /
35 km/h. When driving down steep
hills, the vehicle reduces speed auto-
matically down to about double walking
speed – approx. 7.5 mph / 12 km/h –
and then maintains this speed at a con-
stant.
You can use the accelerator or brakes
to vary this speed within a range from
approx. 3 mph / 5 km/h to approx.
15 mph / 25 km/h.
In conjunction with the multifunction
steering wheel, you can use the +/–
button to set the cruise control to a tar-
get speed in the range from
approx. 3 mph / 5 km/h to approx.
15 mph / 25 km/h.
HDC is automatically deactivated once
vehicle speed again exceeds approx.
37 mph / 60 km/h.
To activate the systemPress the HDC button; the green indi-
cator lamp integrated within the button
comes on.
The indicator lamp flashes whenever
the system is actively intervening to
control your speed with automatic
brake applications.To deactivate the systemPress the button again, the indicator
lamp goes out.
HDC is automatically deactivated once
the vehicle accelerates to more than
37 mph / 60 km/h, as well as whenever
you switch off the ignition.
To use HDCVehicles with manual transmission:
You should always ensure that either
reverse or first gear is engaged before
using HDC, as the engine's braking
effect is most pronounced in these
gears, and only reduced engine braking
is available in higher gears.
Vehicles with automatic transmission:
HDC is available for use in all ranges.System malfunctionsAre signaled by the indicator lamp,
which responds to problems by going
out while HDC is in operation or by fail-
ing to come on when you activate the
system:
HDC has been temporarily deactivated
as a result of high brake temperatures.
If the DSC indicator lamp comes
on at the same time:
Malfunction in HDC and DSC
system. Refer the problem to your
BMW center.
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92
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.

93
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*
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121
General driving notes
Brakes: do not rest your foot on
the brake pedal while driving.
Even light but consistent pedal pres-
sure can lead to high temperatures,
brake wear and possibly even brake
failure.
Hydroplaning: when driving on wet or
slushy roads, reduce road speed. If you
do not, a wedge of water can form
between tires and 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 parcel tray: never use it to store
heavy or hard objects; otherwise, occu-
pants could be injured if the vehicle is
braked hard.
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 87.
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 sys-
tem 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
design of the ABS. When braking while
cornering at high speed or braking dur-
ing high lateral acceleration, or when
braking during a lane change, vehicle
stability is improved and steering
response is enhanced.
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122
Brake systemBrake fluid levelLow brake fluid level in the reservoir
combined with longer than usual pedal
travel may indicate 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. sionally, during extended periods when
the vehicle is not used at all, and in
operating conditions where brake appli-
cations are less frequent, there is an
increased tendency for corrosion of the
rotors and accumulation of contamina-
tion on the brake pads. This occurs
because the minimal pressure that must
be exerted by the pads to clean the
rotors by brake applications is not
reached.
Corrosion on brake rotors is signaled by
a running or pulsation during braking;
even extended subsequent braking will
not cure this phenomenon.
It is a good idea to periodically dry the
brakes with a gentle application when
driving in rain and on wet roads. Watch
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 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.
This helps avoid placing excessive
loads on the brake system. Use care to
avoid exceeding the approved engine-
speed range, refer to page 80.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.
325xi, 330xi: always refer all brake
inspection and service work to your
BMW center, as failure to observe the
special procedures could result in dam-
age 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.<
Brake pads
For your own safety: use only
brake pads which BMW has
approved for your specific 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.<

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. Tire pres-
sure also has a major effect on your
BMW's handling response.
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 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.

125
Do not drive on a 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 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 abnormalities 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-
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.
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. 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.
Tire condition
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