2001 BMW 525I SPORT WAGON overheating

22n
Indicator and warning lampsTechnology that monitors itselfMany of the systems of your BMW
monitor themselves automatically, both
during engine starts and while you are
driving. Indicator and warning lamps
that are identified by "l" are tested for
proper functioning whenever the igni-
tion key is turned. They each light up
once for different periods of time.
If a fault should occur in one of these
systems, the corresponding lamp does
not go out after the engine is started or
it lights up while the vehicle is moving.
You will see how to react to this below.
Red: stop immediately
Battery charge current l
The battery is no longer being
charged. There is a malfunction
of the alternator V-belt or in the charg-
ing circuit of the alternator. Please con-
tact the nearest BMW center.
If the ribbed V-belt is defective, do
not continue driving. The engine
could be damaged due to overheating.
If the ribbed V-belt is defective, in-
creased steering effort is also re-
quired.<
Engine oil pressure l
Comes on while the engine is
running and the "STOP!ENGINE
OILPRESS" message appears in the
Check Control: stop vehicle immedi-
ately and switch off engine. Check level
of oil in engine, top up as required. If oil
level is correct: please contact the
nearest BMW center.
Do not continue driving. The en-
gine could be damaged because
of inadequate lubrication.<
Tire Pressure Control (RDC)
* l
In addition, there is an acousti-
cal warning signal: a tire failure
has occurred. Reduce vehicle speed
immediately and stop the vehicle. Avoid
hard brake applications. Do not over-
steer. For additional information: refer
to page 103.
Parking brake
*,
brake hydraulic system l
Comes on when you engage the
parking brake. For additional informa-
tion: refer to page 70.
Comes on although the parking brake is
released: have the brake fluid level
checked. Before driving further, be
sure to read the notes on pages 146
and 168.
Also comes on with the message
"CHECK BRAKE PADS" in the Check
Control.
Parking brake* warning lamp/
Brake hydraulic system for
Canadian models.

142nCatalytic converter
The catalytic converter reduces harmful
exhaust emissions, and is designed for
use with unleaded fuel only.
Even minute quantities of lead would be
enough to permanently damage both
the catalytic converter and the system
oxygen sensor.
To ensure efficient, trouble-free engine
operation and avoid potential damage:
>Be sure to comply with the scheduled
maintenance requirements.
> Fill the fuel tank well before it is
empty.
> Tow-start the vehicle only when the
engine is cold, since unburned fuel
may otherwise reach the catalytic
converter. It is better to start the vehi-
cle with an outside starting aid. >
Avoid other situations in which the
fuel is not burned, or burns incom-
pletely, such as engaging the starter
frequently or for extended periods, or
repeated start attempts in which the
engine does not start (stopping and
restarting an engine which is running
properly does not present a problem).
Never let the engine run with any of
the spark plug cables disconnected. Be sure to comply with the in-
structions above to prevent un-
burned fuel from reaching the catalytic
converter. Otherwise there is danger of
overheating and damage to the cata-
lytic converter.
Extreme temperatures occur at the cat-
alytic converter on this and every cata-
lyst-equipped vehicle. Heat shields are
installed adjacent to some sections of
the exhaust system. Never remove
these shields; do not apply undercoat-
ing to their surfaces. When driving,
standing at idle, and parking the vehi-
cle, take care to avoid contact between
the exhaust system and flammable ma-
terials (grass, hay, leaves, etc.). Such
contact could lead to a fire, resulting in
personal injury and property damage. <

Index
Data
Technology
Repairs
Car care
Controls
Overview
145nDisc brakes
Driving notes
When driving in wet conditions and in
heavy rain, it is effective 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 rotors.
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
described below (refer to page 147).
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 im-
pairment of the braking effect.
The braking effect of the engine can be
further increased by downshifting, into
first gear, if necessary. In the manual
mode of the automatic transmission,
you can also downshift into first gear.
Refer to page 76. Should engine braking prove inade-
quate, you should still avoid extended,
continuous braking. Instead of main-
taining low to moderate pressure 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 avail-
able at all times.
Do not coast with the clutch de-
pressed or with the transmission
or selector lever in Neutral. Do not
coast 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.
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. <
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. Conventional
braking efficiency is available without
limitations.
Have the system checked and repaired
at your BMW center as soon as possi-
ble.
For "Information for your safety"
covering the ABS system, refer to
page 144. This information also gener-
ally applies for DBC. <

150n
Information for your safety
The factory-approved radial tires are
matched to the car 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 – above all else
– driving safety which 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 –
including the spare tire – regularly
(refer to page 29), at least every two
weeks and before beginning a longer
trip. If this is not done, incorrect tire
pressures can cause driving instability
and tire damage, ultimately resulting in
accidents. <
Tire tread – tire damage
Inspect 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
exceeded. Overloading can lead to
overheating and increases the rate at
which damage develops inside the
tires. The ultimate result can assume
the form of a sudden air loss.
Unusual vibrations encountered during
normal vehicle operation can indicate
tire failure or some other vehicle defect,
as can variations in normal vehicle
response, such as a pronounced ten-
dency to pull to the left or right. Should
this occur, respond by immediately
reducing your speed and carefully
proceeding to the nearest BMW center
or professional tire center, or having 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