air condition BMW 325Ci COUPE 2001 E46 Owner's Guide

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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 120).
Extended or steep mountain descents
should be driven in the gear in which
only minimal periodic brake applica-
tions 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
transmission, you can still downshift
into first gear. Refer to page 67.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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Information for your safetyThe factory-approved radial tires are
matched to the vehicle and have been
selected to provide optimum safety and
driving comfort on your vehicle.
It is not merely the tire's service life, but
also driving comfort and Ð above all else
Ð driving safety that depend on the con-
dition of the tires and the maintenance
of the specified tire pressure.
Incorrect inflation pressure is a frequent
cause of tire damage. It also signifi-
cantly influences the roadholding ability
of your BMW.
Be sure to check the tire inflation
pressure Ð including the space-
saver spare tire or the spare tire Ð on a
regular basis, at least twice a month
and before doing any extended driving.
Refer to page 27. If this is not done, in-
correct tire pressures can cause driving
instability and tire damage, ultimately
resulting in an accident.<
Tire tread Ð 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 0.12 in (3 mm), even though
the legally specified minimum tread
depth is only 0.063 in (1.6 mm). At a
tread depth of 0.063 in (1.6 mm), tread
depth indicators (arrow) in the tread-
groove base indicate that the legally-
permissible wear limit has been
reached. Below 0.12 in (3 mm) tread
depth, there is an increased risk of
aquaplaning, even at relatively moder-
ate speeds and with only small amounts
of water on the road.390de331
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 vehicle so that
the permitted load on the tires is not ex-
ceeded. Overloading can lead to over-
heating and increases the rate at which
damage develops inside the tires. You
could have a blowout as a result.
Unusual vibrations encountered during
normal vehicle operation can indicate
tire failure or some other vehicle defect.
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 and
its tires inspected.
Tire damage (up to and including blow-
outs) can endanger the lives of both the
vehicle occupants and other road
users.<
Tire inflation pressure Tire condition

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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 127.DOT Quality GradesTreadwear
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 as-
phalt 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 tem-
perature 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

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Winter tires

Choosing the right tire

BMW 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, 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
your particular driving conditions.

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 pressure

Winter 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.

Storage

Always 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.

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 mount-
ing the chains.

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IndexDataTechnologyRepairsCar careControlsOverview
Engine oilChecking the oil level 1 Park the vehicle on a level surface.
2 Shut the engine off after it has
reached normal operating tempera-
ture.
3 After approx. 5 minutes, pull the dip-
stick out and wipe it off with a clean
lint-free cloth, paper towel, or similar
material.
4 Carefully push the dipstick all the way
into the guide tube and pull it out
again.
5 The oil level should be between the
two marks on the dipstick.
As with fuel economy, oil consumption
is directly influenced by your driving
style and vehicle operating conditions.462de244
The oil volume between the two marks
on the dipstick corresponds to approx.
1.1 US quarts (1 liter). Do not fill beyond
the upper mark on the dipstick. Excess
oil will damage the engine.460de189
To add oil Wait until the level has dropped to just
above the lower mark before adding oil.
However, never let the oil drop below
the lower mark.
BMW engines are designed to
operate without oil additives; the
use of additives could lead to damage
in some cases. This is also true for the
manual transmission, the automatic
transmission, the differential and the
power steering.<462de245

140n
The BMW Maintenance System has
been designed as a reliable means of
providing maximum driving and oper-
ating safety Ð and as cost-effectively as
possible for you.
Please keep in mind that regular main-
tenance is not only necessary for the
safety of your vehicle, but also plays a
significant role in maintaining the resale
value of the vehicle.
Service Interval DisplayAdvanced technology is employed to
calculate the optimal maintenance
intervals. These are then indicated in
the Service Interval Display. While
conventional systems rely on distance
traveled alone to determine when
service is due, the BMW Maintenance
System has for years considered the 46cus018
actual conditions under which the
vehicle operates, because miles can be
traveled in many different ways:
From a maintenance point of view,
62,000 miles (100,000 km) of short-
distance urban driving are not equiva-
lent to the same distance covered at
moderate speeds in long-distance
highway travel.
The BMW Maintenance System
includes the Engine Oil Service and
Inspections I and II.
Determining the maintenance intervals
according to the actual use of the
vehicle covers every kind of operating
situation. However, even those who
drive only short distances Ð i. e. signifi-
cantly less than 6,000 miles (10,000 km)
annually Ð should have the engine oil
changed at least every 2 years since oil
deteriorates over time, regardless of
use.Service and Warranty Information
Booklet (US models)/Warranty
and Service Guide Booklet
(Canadian models)For additional information on mainte-
nance intervals and procedures, please
refer to the Service and Warranty Infor-
mation Booklet (US models), or the Warranty and Service Guide Booklet
(Canadian models).
As a precaution against rust, it is advis-
able to have the body checked for
damage from rocks or gravel at the
same time, depending upon operating
conditions.
Have your BMW center perform
maintenance and repair.
Your BMW center is always informed on
the latest maintenance work and repair
techniques and equipped with the
required special tools. In addition,
checking parts known from experience
to be subject to wear is a permanent
part of the maintenance specifications.
Be sure that all maintenance work is
confirmed in the Service and Warranty
Information Booklet (US models), or in
the Warranty and Service Guide
Booklet (Canadian models). These
entries are your verification for the
regular maintenance of your vehicle
and are required for the performance of
warranty repairs.<
The BMW Maintenance System

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IndexDataTechnologyRepairsCar careControlsOverview
Battery LocationThe battery is located at the right-rear
of the luggage compartment. Remove
the luggage compartment floor panel
(refer to page 41), and give a screw-
driver or a coin a f turn counterclock-
wise to release the two fasteners plus
an additional fastener in the upper-
center side trim panel to release and
remove. In order to remove the storage
tray, slide the side trim panel slightly
upward.
Battery posts, terminals, and
related accessories contain lead
and lead compounds. Wash hands after
handling.<460de176
Charge conditionYou can read the charge condition
of the battery with the "Magic Eye
*"
(a hydrometer):
>Green: adequate charge.
>Black: not adequately charged. The
battery must be recharged. Please
contact your BMW center for addi-
tional information.
>Yellow: replace the battery.
The service life specified for the
battery can be achieved only if it is
always kept adequately charged. If the
vehicle is primarily used for stop-and-
go traffic, be sure to check the charge
state often.<
460de252
Battery careThe battery is completely maintenance-
free. That means that the original
electrolyte will normally last for the
service life of the battery under
moderate climatic conditions.
For all questions that regard the
battery, please consult your BMW
center. Since the battery is absolutely
maintenance free, the following is for
your information only.<

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IndexDataTechnologyRepairsCar careControlsOverview
Deceleration sensors continuously
monitor the acceleration forces acting
upon the vehicle. If, as the result of a
frontal collision, a deceleration is
reached at which the protection of the
safety belts alone is no longer
adequate, the gas generators of the
driver and passenger-front airbags are
ignited. However, the passenger-side
airbag is only triggered if an additional
sensor has recognized that the
passenger seat is occupied.
In the event of a side collision, the head
and side airbags in the front or rear
* are
triggered if necessary.
390de319
The airbags located under the marked
covers inflate and unfold in a matter of
a few milliseconds. In this process, they
tear through the designed separation
points of the upholstered covers or
press them out.
Because the inflation process must be
virtually instantaneous, it is accompa-
nied by a certain amount of ignition and
inflation noise, which will be drowned
out by the noise from the accident
itself. The gas required to inflate the
airbags is not dangerous, and the
associated smoke then dissipates.
The entire process is completed within
fractions of a second.Highly sensitive sensors monitor the
number of revolutions of the wheels.
When equipped with DSC, they also
monitor steering angle, lateral accelera-
tion, brake pressure and the movement
of the vehicle around its vertical axis.
If differences in the wheel speeds
occur, ASC+T counteracts the danger
of wheelspin by reducing engine
torque; if necessary, ASC+T will also
respond by applying the brakes to the
rear wheels.
In addition, DSC permanently monitors
the vehicle's current operating condi-
tion and compares it with an ideal
condition that is calculated from the
sensor's signals. If deviations from this
occur (understeering or oversteering,
for instance), DSC can stabilize the
vehicle in fractions of a second by
reducing engine output and with the
assistance of braking intervention at
individual wheels. As a result,
dangerous skids can be prevented even
as they are just beginning. But this is
only possible within the laws of physics.
You may need some time to become
accustomed to this system's interven-
tion. However, it provides optimum
drive force and vehicle stability.
The braking intervention may be
accompanied by sounds specific to
the system.
Airbags ASC+T/DSC
*

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IndexDataTechnologyRepairsCar careControlsOverview
Interior rearview mirror with automatic dimming feature
*
The interior rearview mirror with auto-
matic dimming feature reduces blinding
from following traffic by adapting the
intensity of the reflected images to
correspond to levels of light registered
by the unit's sensors. The mirror reverts
to its undimmed setting as soon as the
light source disappears. One lamp
sensor is mounted on the front of the
mirror housing. This sensor, which is
directed forward, measures light inten-
sity in the area ahead of the vehicle.
The second sensor is integrated within
the mirror's glass. The electronic
control system compares the light
intensity from front and rear. The differ-
ence provides the basic parameter
used to modulate an electrical current
and induce chemical changes in a
semisolid layer incorporated in the lens.463us013
The semisolid reacts chemically to this
electrical current, thus providing
dimming of the mirror through an infi-
nitely-variable range (electrochromic
technology).
As a result, it is no longer necessary to
dim the mirror manually, and the driver
can concentrate completely on traffic
conditions.

180n
Self-diagnostics All of the important electrical and elec-
tronic systems in the vehicle are tested
regularly and automatically Ð the driver
does not have to perform any extra
operations or adjustments.
The indicator lamps come on briefly
after the ignition has been turned on.
While you are driving, the functional
status of the actuator motors (for the
windshield wipers, power windows,
seats, sliding/tilt sunroof, etc.) is
constantly being analyzed by electrical
measurements in the relays.462us038
In the same manner, the electrical
resistance of the airbag ignition genera-
tors and all of the remaining airbag
components is measured at all times.
Any fault in this system would be
detected immediately by a current fluc-
tuation that would necessarily accom-
pany it. The fault would be indicated
immediately by the airbag warning
lamp.
Even after you shut off the engine, the
overall functional status of your vehicle
is monitored. For example, all of the
flaps of the heating and ventilation
system travel to the nearest limit posi-
tion. This way you can be assured that
the defrost function is always available,
even if, for example, a defect crops up
in the air conditioner/automatic climate
control during the night while the
engine has been turned off.
A calibration cycle runs every tenth time
the engine is shut off. During this cycle,
the actuator motors of all the heating
and ventilation flaps travel to their limit
stops in both directions. The limit
positions and the return travel paths are
checked in this manner in order to
ensure that appropriate adjustments for
the operating elements can be made at
any time.You will hear the sounds of the air flaps
as the air conditioner/automatic climate
control carries out its self-diagnostic
functions after the ignition has been
shut off. All of the other self-diagnostics
functions operate silently in the back-
ground.
Any possible faults detected during
these self-diagnostics can be read out
and corrected by your BMW center
during the next regularly scheduled
maintenance.