If the anti-lock brake system warning light comes on,
the check tire pressure system may not be working
properly. See your dealer for service. Also, see
Anti-Lock Brake System Warning Light on page 3-45.
The check tire pressure system detects differences in tire
rotation speeds that are caused by changes in tire
pressure. The system can alert you about a low tire – but
it does not replace normal tire maintenance. SeeTires on
page 5-57.
When the LOW TIRE PRESSURE HOLD SET TO
RESET message appears on the Driver Information
Center and the LOW TIRE PRESSURE message comes
on the message center, you should stop as soon as
you can and check all your tires for damage. If a tire is
at, seeIf a Tire Goes Flat on page 5-76. Also check
the tire pressure in all four tires as soon as you can. See
In ation - Tire Pressure on page 5-64.Any time you adjust a tire’s pressure or have one or more
tires repaired or replaced, you’ll need to reset, or
calibrate, the check tire pressure system. You’ll also need
to reset the system whenever you rotate the tires, buy
new tires and install or remove the compact spare.
Do not reset the check tire pressure system without rst
correcting the cause of the problem and checking
and adjusting the pressure in all four tires. If you reset
the system when the tire pressures are incorrect,
the check tire pressure system will not work properly
and may not alert you when a tire is low or high.
To reset the system, do the following:
1. With the engine off, turn the ignition to ON.
2. Press the MODE button until the DIC reads LOW
TIRE PRESSURE HOLD SET TO RESET.
3. Press and hold the SET button until you hear a
chime, and TIRE PRESSURE RESET is displayed.
5-66
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, 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
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.
5-71