2001 BMW 325XI tire type

86n
Tire Pressure Control (RDC)
*
The conceptRDC monitors the tire pressures at all
four wheels, even when the vehicle is
moving. The system provides an alert
whenever the inflation pressure drops
significantly below the specified pres-
sure in one or more tires.
In order for the system to "learn" the
correct tire inflation pressure, check the
inflation pressure in all tires. Refer to
the table of "Tire inflation pressures"
(page 28) and correct the pressures if
necessary. Then activate the system.
This indicator lamp in the instru-
ment cluster will inform you if
the tire pressure is not correct.
Activate the systemDepending on the type of equipment,
the switch either has the letters RDC on
it or the RDC-symbol.
1 Turn the ignition key to position 2
(do not start the engine).
2 Press the switch long enough for the
yellow indicator lamp in the instru-
ment cluster to light up for a few
seconds.
3 After a few minutes driving time, RDC
sets the current inflation pressure in
the tires as the target values to be
monitored.
You will only have to repeat this proce-
dure following a correction of the tire
inflation pressure. Otherwise, RDC
functions automatically when the igni-
tion key is in position 2, and thus oper-
ates whenever the vehicle is driven.460de314
In the event of loss in tire
pressureIf the inflation pressure has dropped
significantly over a long period of time
(which is normal for any tire), the indi-
cator lamp will come on with a yellow
lamp.
This alerts you to have the tires inflated
to the specified pressures as soon as
possible.
If you are prompted to check the
tire pressure shortly after a
correction has been made, this indi-
cates that the corrected values were
not accurate. Please check the inflation
pressure again and make corrections
according to the inflation pressure
table. Then activate the system once
again.<

119n
IndexDataTechnologyRepairsCar careControlsOverview
Antilock Brake System (ABS)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 mislead you into taking
increased risks.
Do not make any modifications to
the ABS system. Service proce-
dures on ABS are to be performed by
authorized technicians only. Cornering Brake Control (CBC) CBC is an advanced engineering devel-
opment of ABS. When braking during
cornering with high lateral accelera-
tion, or when braking during a lane
change, vehicle stability is improved
and the steering response is enhanced.In the event of a fault
If the ABS in the instrument
cluster lights up, refer to
page 22. The brake system then
reverts to conventional operation as on
vehicles without ABS. However, have
the brake system checked by your
BMW center as soon as possible. To
prevent undetected defects and cumu-
lative faults from adversely affecting the
brake system, refer any problems to
your BMW center at the earliest oppor-
tunity.
ABS warning lamp for Canadian
models.
If the brake warning lamp
comes on together with the indi-
cator lamps for ABS and
ASC+T/DSC, refer to page 21,
the entire ABS, CBC and
ASC+T/DSC control system has
failed. Continue driving
cautiously and defensively.
Avoid full brake applications. This could
cause the vehicle to lose stability and
you might no longer be able to control
it.
Have the system checked as soon as
possible by your BMW center.
CBC, ABS and ASC+T/DSC
and
ADB/ADB-X/DBC indicator and
warning lamps for Canadian
models.
Dynamic Brake Control (DBC)*DBC is included in the DSC, refer to
information beginning on page 84.
If you step on the brake rapidly, this
system automatically produces
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 brake warning lamp
comes on. Normal braking effi-
ciency and ABS are still fully available.
Have the system checked and repaired
at your BMW center as soon as
possible.
Please observe the section "Infor-
mation for your safety" concerning
the ABS system, which also applies to
the DSC system.<

122n
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. -34 7 (-37 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 its use, treatment with BMW lock
barrel grease is recommended.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.<
Snow chains 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 situation, it may be appropriate
to deactivate the ASC+T/DSC for a
short period of time. Refer to page 80.
BMW 325xi, 330xi: in a worst-case
scenario, if your vehicle is stuck on one
side or you cannot access one tire, then
a chain may be attached to one rear
wheel for a short period of time.Starting offWhen starting from a full stop in deep
snow or for "rocking" the vehicle to free
it, it may be effective to deactivate the
ASC+T/DSC system. Refer to page 80.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-
grades or slopes, shift down to the next
lower gear at an early point. Maintain an
adequate distance between yourself
and the vehicle ahead.BrakesWinter road conditions substantially
reduce the traction available between
the tires and the road surface.
Remember that braking distances will
be significantly longer as a result.
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 procedure. This type of
staggered braking will reduce the
braking distance, and the vehicle still
remains responsive to steering. It allows
you to steer around hazards once you
have reduced the pressure on the brake
pedal.

128n
Wheel and tire combinations The right choice Use only BMW-approved tires. Refer to
page 130.
Due to the high speeds this vehicle can
reach, the use of specific brands, spec-
ifications and sizes is mandatory.
Consult any BMW center for details.
Comply with local/national regulations.
The correct wheel-tire combina-
tion affects different systems such
as ABS, ATC and ASC+T/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. In the
event of a flat tire, for example, remount
the approved wheel-tire combination as
soon as possible.<
Codes on 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 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 187 mph (300 km/h)
ZR = above 150 mph (240 km/h) Example:
Nominal width
in mm
Aspect ratio in %
Radial tire ID code
Rim diameter in inches
Load rating
(not on ZR tires)
Speed rating
(before R on ZR tires)
205/60 R
1591W
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 15 H 2
J