When a low tire pressure condition is detected,
the TPMS illuminates the low tire pressure warning
light, located in the instrument panel cluster,
and at the same time the LOW TIRE PRESSURE
warning message on the Driver Information
Center (DIC) displays. The low tire pressure
warning light and the DIC warning message
appear at each ignition cycle until the tires are
in ated to the correct in ation pressure. For
additional information and details about the DIC
operation and displays seeDIC Controls and
Displays on page 204andDIC Warnings
and Messages on page 206.
You may notice, during cooler weather conditions,
that the low tire pressure warning light and the
LOW TIRE PRESSURE DIC warning message
may come on when the vehicle is rst started, and
then turn off as you start to drive. This may be
an early indicator that the air pressure in the tire(s)
is getting low and needs to be in ated to the
proper pressure.
Each tire, including the spare (if provided), should
be checked monthly when cold and in ated to
the in ation pressure recommended by the vehicle
manufacturer on the vehicle placard or tire
in ation pressure label. (If your vehicle has tires ofa different size than the size indicated on the
vehicle placard or tire in ation pressure label, you
should determine the proper tire in ation
pressure for those tires.)
As an added safety
feature, your vehicle
has been equipped with
a tire pressure
monitoring system
(TPMS) that illuminates
a low tire pressure
telltale when one
or more of your tires is
signi cantly
under-in ated.
Accordingly, when the low tire pressure telltale
illuminates, you should stop and check your tires
as soon as possible, and in ate them to the
proper pressure. Driving on a signi cantly
under-in ated tire causes the tire to overheat and
can lead to tire failure. Under-in ation also
reduces fuel efficiency and tire tread life, and may
affect the vehicle’s handling and stopping ability.
424
Uniform Tire Quality Grading
Quality grades can be found where applicable on
the tire sidewall between tread shoulder and
maximum section width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration (NHTSA), which
grades tires by treadwear, traction, and
temperature performance. This applies only to
vehicles sold in the United States. The grades are
molded on the sidewalls of most passenger car
tires. The Uniform Tire Quality Grading (UTQG)
system does not apply to deep tread, winter-type
snow tires, space-saver, or temporary use
spare tires, tires with nominal rim diameters of
10 to 12 inches (25 to 30 cm), or to some
limited-production tires.
While the tires available on General Motors
passenger cars and light trucks may vary with
respect to these grades, they must also conform
to federal safety requirements and additional
General Motors Tire Performance Criteria (TPC)
standards.
Treadwear
The treadwear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a speci ed
government test course. For example, a tire
graded 150 would wear one and a half (1.5) times
as well on the government course as a tire
graded 100. The relative performance of tires
depends upon the actual conditions of their use,
however, and may depart signi cantly from
the norm due to variations in driving habits, service
practices, and differences in road characteristics
and climate.
Traction – AA, A, B, C
The traction grades, from highest to lowest, are
AA, A, B, and C. Those grades represent the tire’s
ability to stop on wet pavement as measured
under controlled conditions on speci ed
government test surfaces of asphalt and concrete.
A tire marked C may have poor traction
performance.
Warning:The traction grade assigned to this tire
is based on straight-ahead braking traction
tests, and does not include acceleration, cornering,
hydroplaning, or peak traction characteristics.
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