wheel BMW 325Ci CONVERTIBLE 2001 E46 Owner's Guide

92n
Tire Pressure Control (RDC)
*
In the event of a flat tireIf there is a tire failure with loss of pres-
sure, the indicator lamp comes on with
a red lamp. In addition, an acoustic
signal is sounded.
If this occurs, reduce vehicle speed
immediately to stop the vehicle in a safe
location. Avoid hard brake applications.
Do not oversteer. Replace the wheel
and flat tire.
The space-saver spare tire is
provided for temporary use only in
the event of a flat tire. It does not have
RDC electronics and is not monitored.<
RDC 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 been trained to
work with the RDC system and is
equipped with the necessary special
tools.<
System interferenceLocal devices using the same radio
frequency can interfere with the RDC.
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 RDC
electronics.
>if additional wheels with RDC elec-
tronics are on board.
Please contact your BMW center for
additional information.

Overview
Controls and features
Operation, care
and maintenance
Owner service procedures
Technical data
Index Advanced technology
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IndexDataTechnologyRepairsCar careControlsOverview
Special operating instructions:
Break-in procedures120
Driving notes121
Catalytic converter121
Antilock Brake System
(ABS)122
Disc brakes125
Brake system126
Winter operation127
Power steering129
Cellular phones129
Radio reception129
Hardtop130
Wheels and tires:
Tire inflation pressure132
Tire condition132
Tire replacement133
Tire rotation134
Wheel and tire
combinations135
Winter tires136
Snow chains136
Approved wheel and tire
specifications137Under the hood:
Hood140
Engine compartment142
Washer fluids144
Washer nozzles144
Engine oil145
Coolant147
Brake fluid148
Vehicle Identification
Number149
Care and maintenance:
The BMW Maintenance
System150
Caring for your vehicle151
Cleaning and care of the
convertible top157
Airbags159
Vehicle storage160
Laws and regulations:
Technical modifications161
California Proposition
65 Warning161
OBD interface socket162
Car care

122n
Antilock Brake System (ABS)The concept ABS enhances active safety by helping
to prevent the wheels from locking
under braking. This is because locked
wheels are dangerous. When the front
wheels slide, the driver loses steering
control over the vehicle. Traction loss at
the rear wheels can cause the rear end
to break into an uncontrolled skid.
The system can achieve the shortest
braking distances possible under most
conditions (on straight-aways and in
curves, on asphalt, ice, wet road
surfaces, etc.).
ABS is designed to meet two essential
requirements during every brake appli-
cation:
>To help provide vehicle stability.
>To help maintain steering control and
maneuverability Ð on all types of road
surfaces (asphalt, concrete, mud, wet
road surfaces, snow, ice).
Braking with ABSAt about 6 mph (10 km/h), the system
becomes operative. Whenever the
vehicle's speed drops below approx.
4 mph (6 km/h), the ABS is deactivated.
This means that the wheels can lock in
the final phase of a panic stop Ð a factor
of no significance in actual use.
If you are in a situation that requires full
braking, you will exploit the full benefits
of the ABS system if you apply maxi-
mum brake pressure ("panic stop").
Since the vehicle maintains steering
responsiveness, you can nevertheless
avoid possible obstacles with a
minimum of steering effort.
The ABS system closed-loop control
circuit cycles in fractions of a second.
A pulsation at the brake pedal, together
with the sounds associated with the
hydraulic controls, tells you that the
brake system is within its maximum
limit range and reminds you that you
should adapt road speed to the road
conditions.
On road surfaces that have a loose
surface layer on a firm base with good
traction (on gravel or snow, for
example), or when snow chains are
mounted, braking distances may be
longer than with locked wheels. Nevertheless, ABS possesses the
advantage of vehicle stability and
steering response.
Information for your safetyNot even ABS can suspend the laws of
physics. ABS cannot prevent the
consequences of brake applications
with inadequate clearances for safety
between vehicles, when exceeding the
speed limit, or the risks involved when
aquaplaning occurs. Responsibility for
these types of situations remains in the
hands (and at the feet) of the driver. You
should never allow the added safety of
ABS to lull you into a false sense of
security, or mislead you into taking
increased risks.
Do not make any modifications to
the ABS system.
Service procedures on ABS are to be
performed by authorized technicians
only.<

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IndexDataTechnologyRepairsCar careControlsOverview
Disc brakesDisc brakes furnish optimum decelera-
tion and braking control and greater
fade resistance under heavy use.
When the vehicle is driven only occa-
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
discs 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
discs by brake applications is not
reached.
If the brake discs are corroded, they will
tend to respond to braking with a
pulsating effect that even extended
brake applications will fail to cure.
For your own safety: use only
brake pads that BMW has
approved for your particular vehicle
model. BMW cannot evaluate non-
approved brake pads to determine if
they are suited for use, and therefore
cannot ensure the operating safety of
the vehicle if they are installed.<
Driving notesWhen driving in wet conditions and in
heavy rain, it is effective to apply light
pressure to the brakes every few miles
or kilometers. Be aware of traffic condi-
tions to ensure that this maneuver does
not endanger other road users. The
heat which is generated by the brake
applications helps to dry the brake
pads and discs.
Maximum braking force is obtained
while the wheels are not locked, but
rather when they are still barely turning
immediately prior to locking. ABS main-
tains this state automatically. If the
antilock brake system ever fails, you
should revert to pumping the brakes
(refer to page 128).
Extended or steep mountain descents
should be driven in the gear in which
only minimal periodic brake application
is required. This avoids excessive strain
on the brakes and possible
impairment of the braking effect.
You can further increase the engine's
braking effect by selecting a lower gear,
downshifting as far as first gear. When
driving a vehicle with automatic trans-
mission, you can still downshift into first
gear. Refer to page 74.If engine braking should prove to be
inadequate, you should still avoid
extended, continuous braking. Instead
of maintaining low to moderate pres-
sure over an extended period of time,
you should decelerate by applying
more substantial pressure to the brake
pedal (watch for following traffic),
releasing the pedal, and then repeating
the application (staggered braking). The
cooling phases between active braking
intervals prevent the brakes from over-
heating, thus ensuring that full braking
capacity remains available at all times.
Do not coast with the clutch
depressed or with the shift lever
or selector lever in Neutral. Do not drive
with the engine shut off. The engine
provides no braking effect when the
clutch is depressed or the transmission
is in Neutral, and there is no power-
assist for braking or steering when the
engine is not running. Never allow floor
mats, carpets or any other objects to
protrude into the area around the brake,
clutch or accelerator pedals, which can
obstruct pedal travel.<

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IndexDataTechnologyRepairsCar careControlsOverview
Winter operationThe onset of winter is often accompa-
nied by rapid changes in weather.
Adaptations in driving style should be
accompanied by preparations on the
vehicle itself to ensure that your
progress through the winter remains
safe and trouble-free.CoolantBe sure that the coolant mixture
contains the year-round ratio of 50:50
water and extended-duty antifreeze/
corrosion protection. This mixture
provides protection against freezing
down to approx. Ð34 7 (Ð37 6).
Replace the coolant every four years.LocksBMW door lock deicer can be used to
free them if frozen. This deicer also
contains lubricant.
After using the deicer, we recommend
you treat the door lock with BMW lock
cylinder lubricant.
Rubber seals and components To prevent the weather-stripping from
freezing, apply a spray-on rubber treat-
ment or silicone spray to the door, hood
and luggage compartment lid seals.
A full range of car care products is
available from your BMW center. *
BMW snow chains can be mounted on
both summer and winter tires. Mount
them in pairs on the rear wheels only
and comply with the manufacturer's
safety precautions. Do not exceed a
maximum speed of 30 mph (50 km/h).
In this rare situation, it may be effective
to deactivate the ASC+T/DSC for a
brief period of time. Refer to page 88.
Starting offWhen starting up from a full stop in
deep snow or when "rocking" the
vehicle to free it, it may be effective to
deactivate the ASC+T/DSC system for
a brief period of time. Refer to page 88.Driving on low-traction road
surfacesUse smooth, gentle pressure to control
the accelerator pedal. Avoid excessive
engine speeds and shift to the next
higher gear at an early point. On down-
hill grades or slopes, shift down to the
next lower gear at an early point. Main-
tain an adequate distance between
yourself and the vehicle ahead.

128n
Winter operationBrakesWinter road conditions substantially
reduce the amount of traction available
between the tires and the road surface;
the resulting increase in braking
distance is considerable and should
always be kept in mind.
ABS is intended to prevent the wheels
from locking during brake applications,
thus helping to maintain vehicle stability
and steering response.
If the ABS does not respond in a critical
braking situation and the wheels lock:
reduce the pressure on the brake pedal
until the wheels just start to roll again
while still maintaining enough force to
continue braking.
Then increase the pressure, reduce the
pressure when the wheels lock, reapply
pressure etc.
This staggered braking procedure will
reduce stopping distances while
helping you maintain steering control.
You can then attempt to steer around
hazards after you have reduced pres-
sure on the brake pedal.Do not shift down on slick road
surfaces. Doing so could cause
the rear wheels to lose traction and
skid, that could result in the loss of
vehicle control.<
Depress the clutch during hard
braking on road surfaces that
provide only poor or uneven traction.<
Skid control Depress the clutch and let up on the
accelerator pedal, or place the selector
lever for the automatic transmission in
the "Neutral" position. Countersteer
carefully and attempt to regain control
of the vehicle.
ParkingEngage 1st or reverse gear. If your
vehicle is equipped with an automatic
transmission, place the selector lever in
"Park." On vehicles with manual trans-
mission, also apply the parking brake
when parking on inclined surfaces. In
order to prevent the parking brake pads
from locking due to frost or corrosion,
dry them by gently applying the parking
brake as the vehicle is coming to a
stop. Make sure that following traffic is
not endangered.
The brake lamps do not come
on when the parking brake is
applied.<

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IndexDataTechnologyRepairsCar careControlsOverview
To maintain good handling and vehicle
response, use only tires of a single
tread configuration from a single manu-
facturer. BMW tests and approves
wheel/tire combinations, beginning on
page 137.DOT Quality Grades Treadwear
Traction AA A B C
Temperature A B C
All passenger vehicle tires must
conform to Federal Safety
Requirements in addition to these
grades.< Tread wearThe tread wear grade is a comparative
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 (1g) 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
characteristics.< TemperatureThe temperature grades are A (the
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
temperature can lead to sudden tire
failure. The grade C corresponds to a
level of performance which all
passenger vehicle 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.< Uniform Tire Quality Grading Quality grades can be found where
applicable on the tire sidewall between
tread shoulder and maximum section
width. For example:
Tread wear 200 Traction AA
Temperature A
Do not use retreaded tires. Driving
safety may be impaired by their
use. This is due to the possible varia-
tions in casing structures and, in some
cases, to their extreme age, factors that
can lead to a decrease in their
durability.<
Tire replacement

134n
Tire replacement Tire rotationTire ageThe date on which the tire was manu-
factured is indicated by the code on the
sidewall:
DOT ... 4100 means that the tire was
manufactured in week 41of 2000.
BMW recommends the replacement of
all tires when the tires are no more than
6 years old, even if a tire life of 10 years
is possible.
Spare tires over 6 years old should be
used only in case of emergency. A tire
in this condition should be replaced by
a new tire immediately, and should not
be mounted together with new tires.
Between the axlesThe tread wear patterns at the front end
differ from those at the rear Ð the actual
patterns will vary according to indi-
vidual driving conditions. In the inter-
ests of safety and maintaining optimal
handling characteristics, tire rotation is
not recommended.
If a proposed interaxle rotation of tires
is based on economic considerations,
one should consider whether the costs
for the rotation are likely to be recap-
tured by any increase in the service life
of the tires that might be realized. In
principle, tire rotation must be
performed at short intervals (maximum
3,000 miles/5,000 km). Consult your
BMW center for more information.
Should you decide to rotate the tires,
it is essential to comply with the
following:
Rotate tires on the same side only,
since braking characteristics and road
grip could otherwise be adversely
affected.
Following rotation, the tire inflation
pressure should always be corrected.If different tire sizes are mounted
on the front and rear axles (refer
to page 137), the wheels may not be
rotated from one axle to the other.<

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IndexDataTechnologyRepairsCar careControlsOverview
Wheel and tire combinations The right choice Use only BMW-approved tires, begin-
ning on page 137.
Due to the high speeds this vehicle can
reach, the use of specific brands,
specifications and sizes is mandatory.
Consult any BMW center for details.
Comply with local/national regulations.
The correct wheel/tire combina-
tion has an effect on the different
systems such as ABS, ATC, ASC+T/
DSC
and ADB/DBC whose functioning
would be otherwise impaired if the
incorrect wheel/tire combinations were
used.
For this reason, use only tires of the
same manufacture and tread configura-
tion. In the event of a flat tire, for
example, remount the approved wheel/
tire combination as soon as possible.<
Codes on the tires and wheels The tire codes will aid you in selecting
the correct tire.
The codes on radial tires:
The speed rating indicates the approved
maximum speed for the tire.
Summer tires:
S = up to112 mph (180 km/h)
T = up to 118 mph (190 km/h)
H = up to 130 mph (210 km/h)
V = up to 150 mph (240 km/h)
W = up to 167 mph (270 km/h)
Y = up to 187 mph (300 km/h)
ZR = over 150 mph (240 km/h) Example:
Nominal width
in mm
Aspect ratio in X
Radial tire ID code
Rim diameter in inches
Load rating
(not on ZR tires)
Speed rating
(before R on ZR tires)
225/50 R
1692W
Winter tires and all-season tires:
Q M+S = up to 100 mph (160 km/h)
T M+S = up to 118 mph (190 km/h)
H M+S = up to 130 mph (210 km/h)
Codes stamped on light-alloy wheels:
Protect tire valve from dirt by using
screw-on valve stem caps. Dirt in the
valves frequently leads to slow leaks. Example:
Rim width
in inches
Code letter for
flange type
Symbol for full-drop
center rim
Rim diameter in inches
Hump on the 2 rim shoulders
7 x 16 H 2
J

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Winter tiresChoosing the right tireBMW recommends winter tires (M+S
radial tires) for driving in adverse winter
road conditions. So-called all-season
tires with the M+S identification mark
do indeed possess better winter trac-
tion than summer tires that have the H,
V, W, Y and ZR speed ratings, but they
generally fail to provide the same levels
of performance as winter tires.
In the interest of safe tracking and
steering response, install winter tires
made by the same manufacturer having
the same tread configuration on all four
wheels.
Mount only winter tires which have
been approved by BMW. Any BMW
center will be glad to provide you with
information on the best winter tires for
every particular driving condition.
Do not exceed specified
maximum speeds
Never exceed the maximum speed
for which the tires are rated.
Unprofessional attempts by laymen to
service tires can lead to damage and
accidents.
Have this work performed by skilled
professionals only. Any BMW center
has the required technical knowledge
and the proper equipment and will be
happy to assist you.<
Tire condition, tire pressureWinter tires display a perceptible loss in
their ability to cope with winter driving
conditions once the tread wears to
below 0.16 in (4 mm), and therefore in
the interest of safety, should be
replaced.
Comply with the specified tire inflation
pressures Ð and be sure to have the
wheel and tire assemblies balanced
every time you change the tires.
StorageAlways store tires in a cool, dry place.
Store them away from light whenever
possible. Protect the tires against
contact with oil, grease and fuel.Snow chains
*
Use narrow-link BMW snow chains
on
winter tires only in pairs and only on the
rear wheels. Comply with all manufac-
turer's safety precautions when
mounting the chains.