IndexDataTechnologyRepairsCar careControlsOverview
137n
Catalytic converter Antilock Brake System (ABS)
Be sure to comply with the
instructions above to prevent
unburned fuel from reaching the cata-
lytic converter. Otherwise, the catalytic
converter could respond by over-
heating, leading to serious damage.
Extreme temperatures occur at the
catalytic converter on this and every
catalyst-equipped vehicle. Heat shields
are installed adjacent to some sections
of the exhaust system. Never remove
these shields; do not apply under-
coating to their surfaces. When driving,
standing at idle, and parking the
vehicle, take care to avoid contact
between the exhaust system and flam-
mable materials (grass, hay, leaves,
etc.). Such contact could lead to a fire,
resulting in serious personal injury and
property damage.<
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.
With ABS, you will achieve the shortest-
possible braking distances under all
given conditions (braking while driving
straight ahead or in curves, different
road surfaces).
ABS is designed to meet two essential
requirements during every brake appli-
cation:
>To help provide vehicle stability.
>To help retain steering and maneu-
vering capability on all types of road
surfaces (asphalt, cement, dirt, wet
surfaces, snow and ice).
Braking with ABS The system becomes operative once
the vehicle exceeds a speed of approx.
6 mph (10 km/h). The ABS is inactive
again whenever the vehicle's speed
drops back below approx. 4 mph
(6 km/h).
To shorten the braking distance — espe-
cially on steep, poor road surfaces when
driving slowly straight ahead — the
system allows one or both front wheels
to lock for a short time. Nevertheless,
the vehicle still retains steering
response since this "poor road logic" is
deactivated again automatically as you
steer.
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 avoid possible
obstacles with a minimum of steering
effort, despite the full brake application.
The ABS system's 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
138n
Antilock Brake System (ABS)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, deep sand or snow,
for example), braking distances may be
longer than with locked wheels.This is
also true if snow chains are mounted.
However, ABS continues to provide
enhanced vehicle stability and steering
response under these conditions. Information for your safety Not even ABS can suspend the laws of
physics. ABS alone cannot prevent
accidents when the brakes are applied
without an adequate safety distance
between vehicles, if the vehicle is
driven with excessive speed, or if aqua-
planing 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 that could affect your
own safety and that of others.
Do not make any modifications to
the ABS system.
Service procedures on ABS are to be
performed by authorized technicians
only.<
Cornering Brake Control (CBC) CBC is an advanced engineering
design of the ABS. When braking
during cornering with high lateral accel-
eration, or when braking during a lane
change, vehicle stability is further
improved and the steering response is
enhanced. Electronic Brake Force
Distribution (EBV) EBV governs brake application pres-
sure at the rear wheels to achieve
stable brake response.
If the EBV fails (refer to the next
page), avoid full or "panic" brake
applications. Full or panic brake appli-
cations can result in overbraking at the
rear axle, and braking stability is no
longer ensured.<
Dynamic Brake Control (DBC)
If you apply the brakes rapidly, this
system automatically produces the
maximum braking force boost and thus
helps to achieve the shortest possible
braking distance during "panic stops."
All of the benefits of the ABS system
are exploited under these circum-
stances.
Do not reduce the pressure on the
brake pedal for the duration of the
brake application. When the brake
pedal is released, the DBC is deacti-
vated.
In the event of a malfunction,
the yellow warning lamp comes
on. Have the system checked
and repaired at your BMW
center as soon as possible.
Refer to the "Information for your
safety" covering the ABS system.
This information also applies in general
for DBC.<
IndexDataTechnologyRepairsCar careControlsOverview
139n
Antilock Brake System (ABS) In the event of a fault
If the brake warning lamp
comes on red together with the
yellow indicator lamps for ABS
and DSC (refer to pages 22
to 24), ABS, CBC, DSC, DBC,
EBV and HDC have failed. You
may continue driving, but drive
defensively and with extra
caution. Avoid full brake applications
because the vehicle could become
unstable and go out of control.
Have the system checked by the
nearest BMW center.
If all three warning lamps come on
yellow:
ABS, CBC, DSC, DBC and HDC have
failed. The effect of the EBV Brake
Force Distribution at the rear wheels,
which achieves stable brake response,
is largely preserved. Optimum brake
force and braking stability are no longer
assured. Continue to drive; drive
cautiously and defensively and avoid
full brake applications.
Have the system checked by your BMW
center as soon as possible.
Following an interruption in
battery power, the ABS, CBC,
DSC, DBC and HDC systems are no
longer available. After you drive for only
a few yards or meters or if you turn the
steering wheel from stop to stop while
the vehicle is stationary and the engine
is running, the functions are activated
again and the three warning lamps will
go out.<
Indicator and warning lamps for
Canadian models.
140n
Disc brakes Disc 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 which
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 which even extended
application will fail to cure.
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 suited for use, and therefore
cannot ensure the operating safety of
the vehicle if they are installed.<
Driving notes When driving in wet conditions and in
heavy rain, it is advisable to apply light
pressure to the brake pedal every few
miles (kilometers). Watch 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 continue to rotate,
peaking when the wheels remain on the
verge of locking without actually doing
so. ABS maintains this state automati-
cally. If the ABS fails, you should revert
to the staggered braking technique
(refer to page 142).
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 69.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), then
releasing the pedal, then repeating the
application. This staggered braking
technique allows the brakes to cool in
the intervals between active braking
phases, preventing overheating and
ensuring that full braking capacity
remains available at all times.
Do not coast with the clutch
depressed or with the transmis-
sion 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 transmis-
sion is in neutral, and there is no
power-assist for braking or steering
when the engine is not running.
Have brake inspections performed at
an BMW center only. If you do not,
parts of the four-wheel drive system
could be damaged. Never allow floor
mats, carpets or any other objects to
protrude into the area around the accel-
erator, clutch and brake pedals and
obstruct their movement.<
142n
Winter operation Rubber seals and components In order to prevent the weather-strip-
ping from freezing, apply BMW rubber
treatment or silicone spray to the seals
on the doors, hood and liftgate/tailgate.
A full range of car care products is
available from your BMW center.< Snow chains Mount BMW snow chains
* only on tire
size 235/65 R 17. Always mount chains
in pairs and on the rear wheels only.
Read and comply with the chain manu-
facturer's safety precautions. Do not
exceed a maximum speed of 30 mph
(50 km/h).
Starting offWhen starting in deep snow or
"rocking" the vehicle free, it may be
advisable to deactivate the DSC system
briefly. Refer to page 94.
Driving on low-traction road
surfaces Use smooth, gentle pressure to control
the accelerator pedal. Avoid excessive
engine speeds and shift to the next
higher gear at an early point. Also shift
to the next lower gear at an early point
when approaching grades or slopes.
Maintain an adequate distance
between yourself and the car ahead. BrakingWinter road conditions substantially
reduce the amount of traction available
between the tires and the road surface.
The resulting increases in braking
distance are considerable and should
be kept in mind at all times.
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. Following
that, increase pedal pressure again.
Reduce the pressure as the wheels
lock, then reapply pressure. Repeat this
braking sequence.
This type of staggered braking will
reduce the braking distance, and the
vehicle still remains responsive to
steering.
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 if you want to decelerate.
Doing so could cause the wheels to
lose traction and skid, thus resulting in
the loss of vehicle control.<
Depress the clutch during hard
braking on road surfaces that
provide only poor or uneven traction.<
Index
Data
Technology
Repairs
Car care
Controls
Overview
147nTire replacement Tire rotation
Tire age
The date on which the tire was manu-
factured is indicated by the code on the
sidewall:
DOT ... 4100 indicates that the tire was
manufactured in week 41 of 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.
Although tires may have a theoretical
service life of up to 10 years, BMW
strongly recommends that you replace
all tires after an absolute maximum of
6 years.
Between the axles
The tread wear patterns at the front-
and rear axle are different and will vary
according to individual driving condi-
tions. In the interests of safety and
maintaining optimal handling character-
istics, tire rotation is not recommended.
When considering the potential
economic benefits of interaxle tire rota-
tion, you must decide whether the
expense of having the tires rotated is
likely to be amortized during the antici-
pated extension in tire life. In principle,
interaxle tire rotation should be
performed at short intervals, with a
maximum of 3,000 miles (5,000 km).
Consult your BMW center for more
information.
Should you decide to rotate the tires, it
is essential that you comply with the
following:
Rotate tires on the same side only,
since braking characteristics and road
grip could otherwise be adversely
affected.
Following tire rotation, correct the tire
inflation pressure. If different tire sizes are mounted
on the front and rear axles (refer to
page 150), the wheels may not be
rotated from one axle to the other. <
148n
Wheel and tire combinationsThe right choice
Use only wheels and tires
approved by BMW for the corre-
sponding vehicle model, as otherwise
the tires may make contact with the
body as the result of tolerances despite
the same nominal size being used,
resulting in serious accidents. If non-
approved wheels and tires are used,
BMW cannot evaluate their suitability,
and therefore cannot be held liable for
driving safety.<
For wheel and tire specifications
approved by BMW, refer to page 150.
The correct wheel-tire combina-
tion affects different systems such
as ABS, ATC and DSC. The function of
these systems is impaired if improper
wheel-tire combinations are used.
For this reason, use only tires of the
same brand and tread pattern on the
vehicle and, for example, restore the
approved wheel-tire combination
following a flat tire as soon as
possible.<
Codes on the tires and wheels The code on tires has the following
meaning.
Codes on radial tires:
The speed rating indicates the
approved maximum speed for the tire.
Summer tires:
S = up to 112 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 186 mph (300 km/h)
ZR= over 150 mph (240 km/h) Example:
Nominal width
in mm
Aspect ratio in X
Belt rating code for
radial tires
Rim diameter in inches
Load rating
(not on ZR tires)
Speed rating
(before R on ZR tires)
235/65 R 17 104 H
All-season, all-terrain and winter 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 on light-alloy wheels:
Protect valve stems and valves from dirt
using screw-on valve stem caps. Dirt in
the valves frequently leads to slow
leaks. Storage Store tires in a cool, dry place,
protecting them against light when-
ever possible. Protect the tires against
contact with oil, grease and fuel. Example:
Rim width
in inches
Code letter for
flange type
Symbol for full-drop
center rim
Rim diameter in inches
Special extended hump
on the 2 rim shoulders
7.5 x 17 SEH 2
J
IndexDataTechnologyRepairsCar careControlsOverview
161n
Brake fluid Vehicle Identification
If the indicator lamp for the
brake hydraulic system appears
or if the CHECK BRAKE FLUID
warning appears in the Check
Control: the brake fluid level is
too low in the reservoir.
The brake fluid reservoir is located
under the microfilter housing trim panel
on the driver's side of the vehicle. For
adding brake fluid or for determining
and correcting the cause of brake fluid
loss, consult your BMW center. Your
BMW center is familiar with the specifi-
cations for factory-approved brake
fluids (DOT 4).
Brake fluid loss may result in extended
brake pedal travel. For this situation,
refer to the notes on page 141.
Brake fluid is hygroscopic, that is,
it absorbs moisture from the air
over time.
In order to ensure the safety and reli-
ability of the brake system, have the
brake fluid changed every two years by
a BMW center. Refer also to the Service
and Warranty Information Booklet (US
models) or the Warranty and Service
Guide Booklet (Canadian models).
Brake fluid is toxic and damages the
vehicle's paint. You should always store
it in its original container and in a loca-
tion which is out of reach of children.
Do not spill the fluid and do not fill the
brake fluid reservoir beyond the "MAX"
mark. The brake fluid could ignite upon
contact with hot engine parts and
cause serious burns.<
Comply with the applicable envi-
ronmental laws regulating the
disposal of brake fluid.<
Vehicle Identification NumberIn the engine compartment, stamped
on the right-hand strut dome (arrow)
and on the upper edge of the instru-
ment panel on the left-hand side. 530us103