Cadillac 2011 STS Owner's Manual page 411

Accordingly, when the low tire pressure telltale
illuminates, you should stop and check your tires as
soon as possible, and inflate them to the proper
pressure. Driving on a significantly under inflated tire
causes the tire to overheat and can lead to tire failure.
Under inflation also reduces fuel efficiency and tire
tread life, and may affect the vehicle's handling and
stopping ability.
Please note that the TPMS is not a substitute for proper
tire maintenance, and it is the driver'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.
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
combined with the low tire pressure telltale. When the
system detects a malfunction, the telltale will flash
for approximately one minute and then remain
continuously illuminated. 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. 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.
See
additional information.
See
information regarding Part 15 of the Federal
Communications Commission (FCC) rules and
Industry Canada Standards RSS-210/220/310.
for
for
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