overheating BMW 325XI 2001 Owners Manual

118n
Catalytic converter Antilock Brake System (ABS)
Be sure to comply with the
instructions above to prevent
unburned fuel from reaching the cata-
lytic convertor. If you do not, the cata-
lytic converter could respond by
overheating, 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 extra 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.
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 ABSThe system becomes operative once
the vehicle exceeds a speed of approx.
6 mph (10 km/h). Below approx. 4 mph
(6 km/h), it is once again 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
maximum 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 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.
However, ABS continues to provide
enhanced vehicle stability and steering
response under these conditions.
Information for your safetyNot even ABS can suspend the laws of
physics. ABS cannot prevent the

125n
IndexDataTechnologyRepairsCar careControlsOverview
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
condition of the tires and the mainte-
nance 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.
Check tire inflation pressures
regularly Ð include the space-
saver spare tire or spare tire Ð at least
twice a month and before beginning a
longer trip (refer to page 29). If this is
not done, incorrect tire pressures can
cause driving instability and tire
damage, ultimately resulting in an acci-
dent.<
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
moderate 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
exceeded. Overloading can lead to
overheating 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