Vehicle Care 10-37
RelaysUsage
DRL2 Daytime Running
Lamps 2 Relay
LT/UNLCK Driver Side Unlock
Relay
DRL Daytime Running
Lamps Relay
SPARE Spare
FRT/WSW Front Windshield
Washer RelayWheels and Tires
Tires
Your new vehicle comes with
high-quality tires made by a
leading tire manufacturer. If you
ever have questions about your
tire warranty and where to
obtain service, see your vehicle
Warranty booklet for details.
For additional information refer
to the tire manufacturer.
{WARNING
Poorly maintained and improperly
used tires are dangerous.
.Overloading your tires can
cause overheating as a result
of too much flexing. You
could have an air-out and a
serious accident. See
Vehicle
Load Limits on page 9‑12.
(Continued)
WARNING (Continued)
.Underinflated tires pose the
same danger as overloaded
tires. The resulting accident
could cause serious injury.
Check all tires frequently to
maintain the recommended
pressure. Tire pressure
should be checked when your
tires are cold. See Tire
Pressure on page 10‑44.
.Overinflated tires are more
likely to be cut, punctured or
broken by a sudden
impact —such as when you
hit a pothole. Keep tires at
the recommended pressure.
.Worn, old tires can cause
accidents. If your tread is
badly worn, or if your tires
have been damaged,
replace them.
10-38 Vehicle Care
Tire Sidewall Labeling
Useful information about a tire is
molded into its sidewall. The
examples below show a typical
passenger vehicle tire and a
compact spare tire sidewall.
Passenger (P-Metric) Tire Example
(A) Tire Size:The tire size is a
combination of letters and
numbers used to define a
particular tire's width, height, aspect ratio, construction type,
and service description. See the
“Tire Size”
illustration later in this
section for more detail.
(B) TPC Spec (Tire
Performance Criteria
Specification)
:Original
equipment tires designed to
GM's specific tire performance
criteria have a TPC specification
code molded onto the sidewall.
GM's TPC specifications meet or
exceed all federal safety
guidelines.
(C) DOT (Department of
Transportation)
:The
Department of Transportation
(DOT) code indicates that the
tire is in compliance with the
U.S. Department of
Transportation Motor Vehicle
Safety Standards. (D) Tire Identification Number
(TIN)
:The letters and numbers
following the DOT (Department
of Transportation) code is the
Tire Identification Number
(TIN). The TIN shows the
manufacturer and plant code,
tire size, and date the tire was
manufactured. The TIN is
molded onto both sides of the
tire, although only one side may
have the date of manufacture.
(E) Tire Ply Material
:The type
of cord and number of plies in
the sidewall and under the tread.
(F) Uniform Tire Quality
Grading (UTQG)
:Tire
manufacturers are required to
grade tires based on three
performance factors: treadwear,
traction, and temperature
resistance. For more information
see Uniform Tire Quality
Grading
on page 10‑54.
10-40 Vehicle Care
(F) Tire Size:A combination of
letters and numbers define a
tire's width, height, aspect ratio,
construction type, and service
description. The letter T as the
first character in the tire size
means the tire is for temporary
use only.
(G) TPC Spec (Tire
Performance Criteria
Specification)
:Original
equipment tires designed to
GM's specific tire performance
criteria have a TPC specification
code molded onto the sidewall.
GM's TPC specifications meet or
exceed all federal safety
guidelines.
Tire Designations
Tire Size
The following illustration shows
an example of a typical
passenger vehicle tire size.
(A) Passenger (P-Metric) Tire:
The United States version of a
metric tire sizing system. The
letter P as the first character in
the tire size means a passenger
vehicle tire engineered to
standards set by the U.S. Tire
and Rim Association. (B) Tire Width
:The three-digit
number indicates the tire section
width in millimeters from
sidewall to sidewall.
(C) Aspect Ratio
:A two-digit
number that indicates the tire
height-to-width measurements.
For example, if the tire size
aspect ratio is 60, as shown in
item C of the illustration, it would
mean that the tire's sidewall is
60 percent as high as it is wide.
(D) Construction Code
:A
letter code is used to indicate
the type of ply construction in
the tire. The letter R means
radial ply construction; the
letter D means diagonal or bias
ply construction; and the letter B
means belted-bias ply
construction.
Vehicle Care 10-41
(E) Rim Diameter:Diameter of
the wheel in inches.
(F) Service Description
:These
characters represent the load
index and speed rating of the
tire. The load index represents
the load carry capacity a tire is
certified to carry. The speed
rating is the maximum speed a
tire is certified to carry a load.
Tire Terminology and
Definitions
Air Pressure:The amount of
air inside the tire pressing
outward on each square inch of
the tire. Air pressure is
expressed in psi (pounds per
square inch) or kPa (kilopascal). Accessory Weight
:This
means the combined weight
of optional accessories.
Some examples of optional
accessories are, automatic
transmission, power steering,
power brakes, power windows,
power seats, and air
conditioning.
Aspect Ratio
:The relationship
of a tire's height to its width.
Belt
:A rubber coated layer of
cords that is located between
the plies and the tread. Cords
may be made from steel or other
reinforcing materials.
Bead
:The tire bead contains
steel wires wrapped by steel
cords that hold the tire onto
the rim. Bias Ply Tire
:A pneumatic tire
in which the plies are laid at
alternate angles less than
90 degrees to the centerline of
the tread.
Cold Tire Pressure
:The
amount of air pressure in a tire,
measured in psi (pounds per
square inch) or kPa (kilopascal)
before a tire has built up heat
from driving. See Tire Pressure
on page 10‑44.
Curb Weight
:The weight of a
motor vehicle with standard and
optional equipment including the
maximum capacity of fuel, oil,
and coolant, but without
passengers and cargo.
10-48 Vehicle Care
TPMS Malfunction Light and
Message
The TPMS will not function properly
if one or more of the TPMS sensors
are missing or inoperable. When the
system detects a malfunction, the
low tire warning light flashes for
about one minute and then stays on
for the remainder of the ignition
cycle. A DIC warning message is
also displayed. The low tire warning
light and DIC warning message
come on at each ignition cycle until
the problem is corrected. Some of
the conditions that can cause the
malfunction light and DIC message
to come on are:
.One of the road tires has been
replaced with the spare tire,
if your vehicle has one. The
spare tire does not have a
TPMS sensor. The TPMS
malfunction light and DIC
message should go off once you
re-install the road tire containing
the TPMS sensor.
.The TPMS sensor matching
process was started but not
completed or not completed
successfully after rotating the
vehicle's tires. The DIC message
and TPMS malfunction light
should go off once the TPMS
sensor matching process is
performed successfully. See
“TPMS Sensor Matching
Process”later in this section.
.One or more TPMS sensors are
missing or damaged. The DIC
message and the TPMS
malfunction light should go off
when the TPMS sensors are
installed and the sensor
matching process is performed
successfully. See your dealer/
retailer for service.
.Replacement tires or wheels do
not match your vehicle's original
equipment tires or wheels. Tires
and wheels other than those
recommended for your vehicle
could prevent the TPMS from
functioning properly. See Buying
New Tires on page 10‑52.
.Operating electronic devices or
being near facilities using radio
wave frequencies similar to the
TPMS could cause the TPMS
sensors to malfunction.
If the TPMS is not functioning it
cannot detect or signal a low tire
condition. See your dealer/retailer
for service if the TPMS malfunction
light and DIC message comes on
and stays on.
TPMS Sensor Matching
Process
Each TPMS sensor has a unique
identification code. Any time you
rotate your vehicle's tires or replace
one or more of the TPMS sensors,
the identification codes will need to
be matched to the new tire/wheel
position. The sensors are matched
to the tire/wheel positions in the
following order: driver side front tire,
passenger side front tire, passenger
side rear tire, and driver side rear
tire using a TPMS diagnostic tool.
See your dealer/retailer for service.
Vehicle Care 10-55
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 25 to 30 cm
(10 to 12 inches), 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
specified 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 significantly 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
specified government test
surfaces of asphalt and
concrete. A tire marked C may
have poor traction performance.
Temperature –A, B, C
The temperature grades are
A (the highest), B, and C,
representing the tire's resistance
to the generation of heat and
its ability to dissipate heat
when tested under controlled
conditions on a specified
indoor laboratory test wheel.
Sustained high temperature can
cause the material of the tire to
degenerate and reduce tire life,
10-84 Vehicle Care
10. Now start the vehicle with thegood battery and run the
engine for a while.
11. Try to start the vehicle that had the dead battery. If it will not
start after a few tries, it
probably needs service.
Notice: If the jumper cables are
connected or removed in the
wrong order, electrical shorting
may occur and damage the
vehicle. The repairs would not be
covered by the vehicle warranty.
Always connect and remove the
jumper cables in the correct
order, making sure that the
cables do not touch each other or
other metal.
Jumper Cable Removal
A. Heavy, Unpainted Metal Engine Part or Remote Negative (−)
Terminal
B. Good Battery or Remote Positive (+) and Remote
Negative (−) Terminals
C. Dead Battery or Remote Positive (+) Terminal To disconnect the jumper cables
from both vehicles, do the following:
1. Disconnect the black
negative (−) cable from the
vehicle that had the dead
battery.
2. Disconnect the black negative (−) cable from the
vehicle with the good battery.
3. Disconnect the red positive (+) cable from the vehicle with the
good battery.
4. Disconnect the red positive (+) cable from the other vehicle.
Vehicle Care 10-85
Towing
Towing the Vehicle
To avoid damage, the disabled
vehicle should be towed with all four
wheels off the ground. Consult your
dealer/retailer or a professional
towing service if the disabled
vehicle must be towed.
To tow the vehicle behind another
vehicle for recreational
purposes—such as behind a
motorhome, see Recreational
Vehicle Towing following.
Recreational Vehicle
Towing
Recreational vehicle towing
means towing the vehicle behind
another vehicle –such as behind a
motorhome. The two most common
types of recreational vehicle towing
are known as dinghy towing and
dolly towing. Dinghy towing is
towing the vehicle with all four
wheels on the ground. Dolly towing
is towing the vehicle with two
wheels on the ground and two
wheels up on a device known as
a dolly. Here are some important things to
consider before recreational vehicle
towing:.What is the towing capacity
of the towing vehicle?
Be sure to read the tow
vehicle manufacturer's
recommendations.
.What is the distance that will be
travelled? Some vehicles have
restrictions on how far and how
long they can tow.
.Is the proper towing equipment
going to be used? See your
dealer/retailer or trailering
professional for additional
advice and equipment
recommendations.
.Is the vehicle ready to be
towed? Just as preparing the
vehicle for a long trip, make sure
the vehicle is prepared to be
towed.