2001 BMW M ROADSTER COUPE sensor

26n
Refueling Fuel specifications Tire inflation pressure
When handling fuels, comply with
all of the applicable safety precau-
tions displayed at gas stations.
Never carry spare fuel containers in
your vehicle. Whether they are empty or
full, these containers can leak, cause an
explosion, or lead to fire in the event of
a collision.<
The engine uses lead-free gasoline
only.
Required fuel:
>Premium Unleaded Gasoline,
min. 91 AKI.
AKI = Anti Knock Index
Do not use leaded fuels. The use
of leaded fuels will cause perma-
nent damage to the system's oxygen
sensor and the catalytic converter.<
The inflation pressures are indicated on
a label attached to the B-pillar behind
the driver's door (visible with door
open).Check tire pressuresOn the next page you will find all pres-
sure specifications, indicated in psi
(kilopascal [kPa]) with the tires at
ambient temperature.
After correcting the tire inflation
pressure, re-initialize the Tire
Pressure Warning (RDW) system, refer
to page 67.<367de388
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88n
Catalytic converterThe catalytic converter reduces harmful
exhaust emissions.
It 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's oxygen sensor.
To ensure efficient, trouble-free engine
operation and to 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. Tow-starting when the
engine is warm could cause unburned
fuel to ignite to the catalytic converter,
resulting in significant damage. It is
better to start the vehicle with an
outside starting aid.>Avoid any other situations in which
the fuel would not be (completely)
burned, for instance:
Frequent or consecutive extended
starting attempts or repeated starting
attempts when the engine fails to
start. (Shutting down and restarting
an engine which is running properly
does not present a problem.)
Never let the engine run with any of
the spark plug connectors discon-
nected.Be sure to comply with the
instructions above to prevent
unburned fuel from reaching the cata-
lytic converter. This could cause over-
heating, leading to serious damage to
the catalytic converter.
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 while the engine
is idling, or when parking, be careful to
avoid contact between the hot exhaust
system and easily-flammable materials
(hay, dry grass, leaves, etc.). Such
contact could cause a fire, resulting in
personal injuries and property
damage.<
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150n
Deceleration sensors continuously
monitor the physical forces acting upon
the vehicle. In the event of a severe
frontal impact, the gas generators of
the driver- and passenger-side front
airbags are ignited simultaneously.
However, the passenger-side front
airbag is only triggered if an additional
sensor has recognized that the
passenger seat is occupied.
If it is necessary during a side impact, a
side airbag will be triggered on the side
where the collision occurs.
390de012
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 breaking
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 it dissipates together
with the associated smoke.
The entire process is completed within
a fraction of a second.The AM frequency bands (medium-
wave, long-wave and short-wave) make
it possible to receive stations from a
great distance, because the broadcast
signals travel not only along the ground
as surface waves, but also as atmos-
pheric waves that are reflected from the
ionosphere.
Frequency-modulation (FM) provides
substantially better sound quality than
the other frequencies. However,
because FM transmissions rely on line-
of-sight broadcast waves, their effec-
tive reception range is limited.
The limitations which are inherent to
radio reception in a moving vehicle
have been minimized by the use of
innovative systems.
365de062
Airbags Radio reception
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151n
IndexDataTechnologyRepairsCar careControlsOverview
Highly sensitive sensors monitor the
number of revolutions of the wheels,
steering angle, lateral acceleration,
brake pressure and the movement of
the vehicle around its vertical axis.
If differences in wheel revolutions
should occur, the system will recognize
the potential danger this loss of traction
can cause and reduces the drive torque
going to the wheels. The system will
also apply the brakes to all four wheels,
if necessary.
In addition, DSC permanently monitors
the vehicle's current operating condi-
tion and compares it with an ideal
condition that is calculated from the
sensor's signals.
If conditions such as understeering or
oversteering should occur, DSC will
help stabilize the vehicle in fractions of
a second by reducing engine power
output, and applying the brakes to indi-
vidual wheels.
As a result, many dangerous skids can
be prevented even as they are just
beginning, within physically feasible
limits.You may need some time to become
accustomed to this system's interven-
tion. However, it provides optimum
drive force and vehicle stability.
The braking intervention may be
accompanied by a certain degree of
noise.
The safety belt tensioner responds to
severe frontal impacts by tightening the
belts to ensure that occupants remain
firmly positioned in their seats. A gas-
pressure system retracts the buckle
assembly to tension the shoulder and
lap belts within fractions of a second.
This tends to further reduce the
tendency to slide under the lap belt.
390de330
Dynamic Stability Control (DSC) Safety belt tensioner
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152n
Interior rearview mirror with automatic dimming featureThe 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 light sensor is mounted on the
front of the mirror housing. This sensor
is directed forward. It measures light
intensity in the area ahead of the
vehicle. A second light sensor is
located on the lower edge of the mirror.
The electronic control system
compares the light intensity from front
and rear. The difference provides the
basic parameter used to modulate an
electrical current and induce chemical 367de398
changes in a semisolid layer incorpo-
rated in the lens.
The semisolid reacts chemically to this
electrical current, thus providing infi-
nitely variable dimming of the mirror
(electrochromic technology).
As a result, it is no longer necessary to
dim the inside rearview mirror manually,
and the driver can concentrate
completely on traffic conditions.
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