2001 BMW 320i sensor

99n
IndexDataTechnologyRepairsCar careControlsOverview
Automatic climate control
*
1 Air on the windshield and on the
side windows
2 Air flow toward the upper body
The side rotary dials allow you to
open and close the air supply
through an infinitely-variable range,
while the levers change the air flow
direction. The center rotary dial
controls the temperature of the air
as it flows out. Refer to page 102
3 Front footwell ventilation
There are corresponding air vents in
the rear footwell as well
4 Recirculated air mode/Automatic
recirculated air control (AUC)101
5 Air supply101
6 Temperature100
7 Automatic air distribution100
8 Individual air distribution100
9 Air grill for interior temperature
sensor Ð please keep clear and
unobstructed
10 Display for temperature and air
supply100
11 Defrost the windshield and side
windows101
12 Air conditioner101
13 Rear window defroster71, 102

117n
IndexDataTechnologyRepairsCar careControlsOverview
Brakes:
Do not drive with your foot resting
on the brake pedal. Even light but
consistent pedal pressure can lead to
high temperatures, brake wear, and
possibly to brake failure.
Aquaplaning:
Reduce your speed when you drive on
wet or slushy roads. If you do not, a
wedge of water can form between the
tires and the road surface. This
phenomenon is referred to as aqua-
planing or hydroplaning. It is character-
ized by a partial or complete loss of
contact between the tires and the road
surface. The ultimate results are loss of
steering and braking control.
Driving through water:
Do not drive through water that is
deeper than 1 foot (30 cm). If you must
drive through water accumulations up
to that depth, drive only at walking
speed. Driving at a faster speed could
cause damage to the engine, the elec-
trical systems and the transmission.
Package tray:
Never use the rear window shelf to
store heavy or bulky objects. If you do
so, such objects could pose the risk of
injury to vehicle occupants during
braking or evasive maneuvers or in a
crash.
Clothes hooks:
When suspending clothing from the
hooks, be sure that they will not
obstruct the driver's vision. Do not hang
heavy objects on the hooks. If you do
so, such objects could pose the risk of
personal injury during braking or
evasive maneuvers. 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 only when the engine is
cold. If you attempt to tow-start with
a warm engine, unburned residual
fuel in the catalytic converter could
ignite and cause damage. It is better
to jump-start the vehicle with outside
assistance.
>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 allow the engine to run with
any of the spark plug cables discon-
nected.
Driving notes Catalytic converter

146n
Washing your vehicle You can have your BMW washed in
an automatic car wash, even when it
is new. Car wash systems that do not
employ brushes are preferable.
Wipe away tough dirt and loosen and
remove dead insects before washing
the vehicle.
In order to avoid spots, do not wash the
vehicle when the hood is warm, or
during or immediately after exposure to
strong sunlight.
When using an automatic car wash, be
sure that:
>The car wash system is suited for the
dimensions of your vehicle.
>No damage will occur on vehicles
with attached body accessories (such
as spoilers or antennas). Consult the
car wash operator if necessary.
>The wheels and tires of your vehicle
cannot be damaged by the convey-
ance devices of the car wash system.
>The vehicle is cleaned with minimum
brush pressure, and that ample water
is available for washing and rinsing.Vehicles with rain sensor:
Clean the windshield regularly. Wax
from automatic car washes or insects
can cause malfunctions in the function
of the rain sensor.
Deactivate the rain sensor
(refer to page 70) when passing
through an automatic car wash. Failure
to do so could result in damage caused
by unintended wiper activation.<
Parts of the vehicle that are
inaccessible to the automatic washer Ð
such as door sills, door and hood
edges, etc. Ð should be cleaned by
hand.
In the winter months, it is especially
important to be sure that the vehicle is
washed on a regular basis. Large quan-
tities of dirt and road salt are difficult to
remove, and they also cause damage
to the vehicle.
If spray wands or high-pressure
washers are used, be sure to
maintain an adequate distance between
the spray source and the vehicle's
surface. Inadequate distance and
excessive pressure can damage or
weaken the finish, making it more
susceptible to subsequent attack. In
addition, moisture could penetrate to
vehicle components, leading to long-
term damage.<
When cleaning the headlamps,
please observe the following:
Do not clean by wiping with a dry cloth
(this causes scratches). Never use
abrasives or strong solvents. Remove
dirt and contamination (such as insects)
by soaking with BMW Car Shampoo
and then rinsing with plenty of water.
Always use a deicer spray to remove
accumulated ice and snow Ð never use
a scraper.<
After washing the vehicle, apply
the brakes briefly to dry them.
Braking efficiency might otherwise be
reduced by the moisture and the brake
rotors could also be corroded.<
Caring for your vehicle

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IndexDataTechnologyRepairsCar careControlsOverview
Caring for your vehicleWindow careYou can use window and glass cleaner
to clean inside window surfaces and
mirrors without smearing and streaking.
Never use polishing pastes or abrasive
(quartz) cleansers on mirror lenses.
Clean the wiper blades with soapy
water. The wiper blades should be
replaced twice a year Ð before and
after the cold season. This is especially
important for vehicles with a rain
sensor.
Use only wiper blades approved
by BMW.<
Caring for other vehicle
components and materials Light-alloy wheels should be treated
with alloy wheel cleaner, especially
during the winter months. However, do
not use aggressive products contain-
ing acids, strong alkalis or abrasives.
Do not use steam cleaners operating at
temperatures above 140 7 (+60 6).
Follow the manufacturer's instructions.
If your vehicle has chrome parts
* such
as the window frames and door handles,
clean these parts carefully with ample
clean water and a shampoo supplement
if desired, especially if they have an
accumulation of road salt. Use chrome
polish as an additional treatment.
Plastic components, vinyl upholstery,
headliners, lamp lenses, the clear cover
of the instrument panel and compo-
nents with a sprayed dull black surface
can be cleaned with water (add plastic
shampoo as required). Do not allow
moisture to soak through the seats or
headliner. Never use solvents such as
lacquer thinner, heavy-duty grease
remover, fuels, or similar substances.
Rubber components should be cleaned
with water only; a rubber treatment or
silicone spray may also be applied.Do not remove safety belts to clean
them. Clean them with mild soapy
water only. Do not use chemicals or dry
cleaners to clean safety belts, since this
could damage the belt fabric.
After cleaning, never allow the inertia
reel to retract the belts until they are
completely dry. Dirty safety belts
prevent the inertia reel mechanism from
retracting the strap properly, and thus
constitute a safety hazard.
Heavily soiled floor carpets and mats
*
can be cleaned with an interior cleaner.
The floor mats can be removed from
the vehicle for cleaning.
Use only a damp cloth to clean trim
panels made of real wood
* and other
parts constructed of real wood
*. Follow
up by drying with a soft cloth.
Use cleaning and car-care
products that you can obtain at
your BMW center.<

Overview
Controls and features
Operation, care
and maintenance
Owner service procedures
Technical data
Index Advanced technology
177n
IndexDataTechnologyRepairsCar careControlsOverview
Adaptive Transmission Control
(ATC)178
Airbags179
Automatic Stability Control plus
Traction (ASC+T)/Dynamic
Stability Control (DSC)180
Radio reception181
Four-wheel drive182
Safety belt tensioner183
Interior rearview mirror
with automatic dimming
feature184
Rain sensor185
Tire Pressure Control (RDC)186
Self-diagnostics187
Xenon lamps188
Technol-

179n
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 simultaneously. 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
protection and side airbags in the front
and 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 necessarily
accompanied by a certain amount of
ignition and inflation noise. The gas
required to inflate the airbags is not
dangerous, and the smoke associated
with it dissipates.
The entire process is completed within
fractions of a second.
Airbags

180n
ASC+T/DSC
*
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 will also respond by
applying the brakes to the rear wheels.
In addition, DSC permanently monitors
the vehicle's current operating condition
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 only 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 driving stability.
The braking intervention may be
accompanied by sounds specific to the
system.

184n
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.