Mercedes-Benz S 450 4MATIC Operator's Manual page 596

Warning!
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recom-
mended by the vehicle manufacturer on the
vehicle Tire and Loading Information placard
or the tire inflation pressure label. If your ve-
hicle has tires of a different size than the
size indicated on the vehicle Tire and Load-
ing Information placard or the tire inflation
pressure label, you should determine the
proper tire inflation pressure for those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitor-
ing system (TPMS) that illuminates a low tire
pressure telltale when one or more of your
tires is significantly underinflated. Accord-
ingly, when the low tire pressure telltale illu-
minates, you should stop and check your
tires as soon as possible, and inflate then to
the proper pressure. Driving on a significant-
ly underinflated tire causes the tire to over-
heat and can lead to tire failure.
G
Under-inflation also reduces fuel efficiency
and tire tread life, and may effect the vehi-
cle's handling and stopping ability. Please
note that the TPMS is not a substitute for
proper tire maintenance, and it is the driv-
er's responsibility to maintain correct tire
pressure, even if under-inflation has not
reached the level to trigger illumination of
the TPMS low tire pressure telltale.
USA only:
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate
when the system is not operating properly.
The TPMS malfunction indicator is com-
bined with the low tire pressure telltale.
When the system detects a malfunction, the
telltale will flash for approximately
one minute and then remain continuously il-
luminated. This sequence will continue upon
subsequent vehicle start-ups as long as the
malfunction exists. When the malfunction
indicator is illuminated, the system may not
be able to detect or signal low tire pressure
as intended.
Operation
Tires and wheels
TPMS malfunctions may occur for a variety
of reasons, including the installation of
replacement or alternate tires or wheels on
the vehicle that prevent the TPMS from
functioning properly. Always check the
TPMS malfunction telltale after replacing
one or more tires or wheels on your vehicle
to ensure that the replacement or alternate
tires and wheels allow the TPMS to continue
to function properly.
i
If a condition causing the TPMS to malfunc-
tion develops, it may take up to 10 minutes for
the system to signal a malfunction using the
TPMS telltale flashing and illumination se-
quence.
The telltale extinguishes after a few minutes driv-
ing if the malfunction has been corrected.
i
Operating radio transmission equipment
(e.g. wireless headsets, two-way radios) in or
near the vehicle could cause the TPMS to mal-
function.
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