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DRIVING AND OPERATING 257
.Objects that are close to the front of
your vehicle.
ACC Automatically Disengages
ACC may automatically disengage and
you will need to manually apply the
brakes to slow the vehicle when:
.The sensors are blocked.
.The Traction Control System (TCS)
or StabiliTrak/ESC system has
activated or been disabled.
.There is a fault in the system.
.The radar falsely reports blockage
when driving in a desert or remote
area with no other vehicles or
roadside objects. A DIC message
may display to indicate that ACC is
temporarily unavailable.
The ACC indicator will turn white
when ACC is no longer active.
In some cases, when ACC will not
activate, regular Cruise Control may
be used. See “Switching Between ACC
and Regular Cruise Control ”previously
in this section. Always consider
driving conditions before using either
cruise control system. Notification to Resume ACC
ACC will maintain a follow gap behind
a detected vehicle and slow your
vehicle to a stop behind that vehicle.
If the stopped vehicle ahead has
driven away and ACC has not
resumed, the vehicle ahead indicator
will flash as a reminder to check
traffic ahead before proceeding. In
addition, the left and right sides of the
Safety Alert Seat will pulse three
times, or three beeps will sound. See
“Alert Type
”and “Adaptive Cruise Go
Notifier” in“Collision/Detection
Systems” underVehicle Personalization
0 117.
When the vehicle ahead drives away,
ACC resumes automatically if the stop
was brief. If necessary, press RES+ or
the accelerator pedal to resume ACC.
If stopped for more than two minutes
or if the driver door is opened and the
driver seat belt is unbuckled, the ACC
automatically applies the Electric
Parking Brake (EPB) to hold the
vehicle. The EPB status light will turn
on. See Electric Parking Brake 0237.
To release the EPB, press the
accelerator pedal. A DIC warning message may display
indicating to shift to P (Park) before
exiting the vehicle.
{Warning
If ACC has stopped the vehicle, and
if ACC is disengaged, turned off,
or canceled, the vehicle will no
longer be held at a stop. The vehicle
can move. When ACC is holding the
vehicle at a stop, always be
prepared to manually apply the
brakes.
{Warning
Leaving the vehicle without placing
it in P (Park) can be dangerous. Do
not leave the vehicle while it is
being held at a stop by ACC. Always
place the vehicle in P (Park) and
turn off the ignition before leaving
the vehicle.
ACC Override
If using the accelerator pedal while
ACC is active, the ACC indicator turns
blue on the instrument cluster and in
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306 VEHICLE CARE
California Perchlorate
Materials Requirements
Certain types of automotive
applications, such as airbag initiators,
seat belt pretensioners, and lithium
batteries contained in electronic keys,
may contain perchlorate materials.
Perchlorate Material–special
handling may apply. See
www.dtsc.ca.gov/hazardouswaste/
perchlorate.
Accessories and
Modifications
Adding non-dealer accessories or
making modifications to the vehicle
can affect vehicle performance and
safety, including such things as
airbags, braking, stability, ride and
handling, emissions systems,
aerodynamics, durability, and
electronic systems like antilock
brakes, traction control, and stability
control. These accessories or
modifications could even cause
malfunction or damage not covered by
the vehicle warranty. Damage to suspension components
caused by modifying vehicle height
outside of factory settings will not be
covered by the vehicle warranty.
Damage to vehicle components
resulting from modifications or the
installation or use of non-GM certified
parts, including control module or
software modifications, is not covered
under the terms of the vehicle
warranty and may affect remaining
warranty coverage for affected parts.
GM Accessories are designed to
complement and function with other
systems on the vehicle. See your
dealer to accessorize the vehicle using
genuine GM Accessories installed by a
dealer technician.
Also, see
Adding Equipment to the
Airbag-Equipped Vehicle 058.
Vehicle Checks
Doing Your Own
Service Work
{Warning
It can be dangerous to work on
your vehicle if you do not have the
proper knowledge, service manual,
tools, or parts. Always follow
owner’s manual procedures and
consult the service manual for your
vehicle before doing any
service work.
If doing some of your own service
work, use the proper service manual.
It tells you much more about how to
service the vehicle than this manual
can. To order the proper service
manual, see Publication Ordering
Information 0408.
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340 VEHICLE CARE
all-season tires can be identified by
the last two characters of this TPC
code, which will be“MS.”
Consider installing winter tires on the
vehicle if frequent driving on snow or
ice-covered roads is expected.
All-season tires provide adequate
performance for most winter driving
conditions, but they may not offer the
same level of traction or performance
as winter tires on snow or ice-covered
roads. See Winter Tires 0340.
Winter Tires
This vehicle was not originally
equipped with winter tires. Winter
tires are designed for increased
traction on snow and ice-covered
roads. Consider installing winter tires
on the vehicle if frequent driving on
ice or snow covered roads is expected.
See your dealer for details regarding
winter tire availability and proper tire
selection. Also, see Buying New Tires
0 354.
With winter tires, there may be
decreased dry road traction, increased
road noise, and shorter tread life. After changing to winter tires, be alert
for changes in vehicle handling and
braking.
If using winter tires:
.Use tires of the same brand and
tread type on all four wheel
positions.
.Use only radial ply tires of the same
size, load range, and speed rating as
the original equipment tires.
Winter tires with the same speed
rating as the original equipment tires
may not be available for H, V, W, Y,
and ZR speed rated tires. If winter
tires with a lower speed rating are
chosen, never exceed the tire's
maximum speed capability.
Run-Flat Tires
This vehicle, when new, may have had
run-flat tires. There is no spare tire,
no tire changing equipment, and no
place to store a tire in the vehicle.
{Warning
While driving with run-flat tires at
a reduced inflation pressure, avoid
making sudden stops or severe
maneuvers as the handling
capabilities of the tires will be
reduced. Driving too fast could
cause loss of control and you or
others could be injured. Do not
drive over 80 km/h (50 mph) with
the tire operating at low pressure.
Drive cautiously and check the tire
pressure as soon as possible.
Run-flat tires can be driven up to
80 km (50 mi) at speeds less than
80 km/h (50 mph) after a loss of
inflation pressure has occurred. There
is no need to stop on the side of the
road to change the tire. The possible
driving range after a pressure loss will
vary based on the vehicle load and
driving conditions. As soon as
possible, contact the nearest
authorized GM or run-flat servicing
facility for inspection and repair or
replacement.
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354 VEHICLE CARE
Treadwear indicators are one way to
tell when it is time for new tires.
Treadwear indicators appear when the
tires have only 1.6 mm (1/16 in) or
less of tread remaining. SeeTire
Inspection 0352 and
Tire Rotation 0352 for additional
information.
The rubber in tires ages over time.
This also applies to the spare tire,
if the vehicle has one, even if it is
never used. Multiple factors including
temperatures, loading conditions, and
inflation pressure maintenance affect
how fast aging takes place. GM
recommends that tires, including the
spare if equipped, be replaced after six years, regardless of tread wear. To
identify the age of a tire, use the tire
manufacture date, which is the last
four digits of the DOT Tire
Identification Number (TIN) molded
into one side of the tire sidewall. The
last four digits of the TIN indicate the
tire manufactured date. The first two
digits represent the week and the last
two digits, the year. For example, the
third week of the year 2020 would
have a 4-digit DOT date of 0320. Week
01 is the first full week (Sunday
through Saturday) of each year.
Vehicle Storage
Tires age when stored normally
mounted on a parked vehicle. Park a
vehicle that will be stored for at least
a month in a cool, dry, clean area
away from direct sunlight to slow
aging. This area should be free of
grease, gasoline, or other substances
that can deteriorate rubber.
Parking for an extended period can
cause flat spots on the tires that may
result in vibrations while driving.
When storing a vehicle for at least a
month, remove the tires or raise the
vehicle to reduce the weight from the
tires.
Buying New Tires
GM has developed and matched
specific tires for the vehicle. The
original equipment tires installed
were designed to meet General
Motors Tire Performance Criteria
Specification (TPC Spec) system
rating. When replacement tires are
needed, GM strongly recommends
buying tires with the same TPC
Spec rating.
GM's exclusive TPC Spec system
considers over a dozen critical
specifications that impact the
overall performance of the vehicle,
including brake system
performance, ride and handling,
traction control, and tire pressure
monitoring performance. GM's
TPC Spec number is molded onto
the tire's sidewall near the tire
size. If the tires have an all-season
tread design, the TPC Spec
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356 VEHICLE CARE
Different Size Tires and
Wheels
If wheels or tires are installed that are
a different size than the original
equipment wheels and tires, vehicle
performance, including its braking,
ride and handling characteristics,
stability, and resistance to rollover
may be affected. If the vehicle has
electronic systems such as antilock
brakes, rollover airbags, traction
control, electronic stability control,
or All-Wheel Drive, the performance
of these systems can also be affected.
{Warning
If different sized wheels are used,
there may not be an acceptable
level of performance and safety if
tires not recommended for those
wheels are selected. This increases
the chance of a crash and serious
injury. Only use GM specific wheel
and tire systems developed for the
vehicle, and have them properly
installed by a GM certified
technician.See
Buying New Tires 0354 and
Accessories and Modifications 0306.
Uniform Tire Quality
Grading
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 tires, compact 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.
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
All Passenger Car Tires Must
Conform to Federal Safety
Requirements In Addition To
These Grades.
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 one-half
(1½) times as well on the
government course as a tire
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VEHICLE CARE 357
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
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. 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.Temperature
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,
and excessive temperature can
lead to sudden tire failure. The
grade C corresponds to a level of
performance which all passenger
car tires must meet under the
Federal Motor Safety Standard
No. 109. Grades B and A represent
higher levels of performance on
the laboratory test wheel than the
minimum required by law.
Warning: The temperature grade
for this tire is established for a tire
that is properly inflated and not
overloaded. Excessive speed,
underinflation, or excessive
loading, either separately or in
combination, can cause heat
buildup and possible tire failure.
Wheel Alignment and Tire
Balance
The tires and wheels were aligned and
balanced at the factory to provide the
longest tire life and best overall
performance. Adjustments to wheel
alignment and tire balancing are not
necessary on a regular basis. Consider
an alignment check if there is unusual
tire wear or the vehicle is significantly
pulling to one side or the other. Some
slight pull to the left or right,
depending on the crown of the road
and/or other road surface variations
such as troughs or ruts, is normal.
If the vehicle is vibrating when driving
on a smooth road, the tires and
wheels may need to be rebalanced.
See your dealer for proper diagnosis.
Wheel Replacement
Replace any wheel that is bent,
cracked, or badly rusted or corroded.
If wheel nuts keep coming loose, the
wheel, wheel bolts, and wheel nuts
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358 VEHICLE CARE
should be replaced. If the wheel leaks
air, replace it. Some aluminum wheels
can be repaired. See your dealer if any
of these conditions exist.
Your dealer will know the kind of
wheel that is needed.
Each new wheel should have the same
load-carrying capacity, diameter,
width, offset, and be mounted the
same way as the one it replaces.
Replace wheels, wheel bolts, wheel
nuts, or Tire Pressure Monitor System
(TPMS) sensors with new GM original
equipment parts.
{Warning
Using the wrong replacement
wheels, wheel bolts, or wheel nuts
can be dangerous. It could affect
the braking and handling of the
vehicle. Tires can lose air, and
cause loss of control, causing a
crash. Always use the correct wheel,
wheel bolts, and wheel nuts for
replacement.
Caution
The wrong wheel can also cause
problems with bearing life, brake
cooling, speedometer or odometer
calibration, headlamp aim, bumper
height, vehicle ground clearance,
and tire or tire chain clearance to
the body and chassis.
Used Replacement Wheels
{Warning
Replacing a wheel with a used one
is dangerous. How it has been used
or how far it has been driven may
be unknown. It could fail suddenly
and cause a crash. When replacing
wheels, use a new GM original
equipment wheel.
Tire Chains
{Warning
If the vehicle has 235/40R18 or
235/35R19 size tires, do not use tire
chains. There is not enough
clearance. Tire chains used on a
vehicle without the proper amount
of clearance can cause damage to
the brakes, suspension, or other
vehicle parts. The area damaged by
the tire chains could cause loss of
control and a crash. Use another
type of traction device only if its
manufacturer recommends it for
the vehicle's tire size combination
and road conditions. Follow that
manufacturer's instructions. To
avoid vehicle damage, drive slow
and readjust or remove the traction
device if it contacts the vehicle. Do
not spin the wheels. If traction
devices are used, install them on
the rear tires.
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INDEX 423
Chains, Tire . . . . . . . . . . . . . . . . . . . . . . . . . 358
ChargingWireless . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
Charging System Light . . . . . . . . . . . . . . 97
Check Engine Light (MalfunctionIndicator) . . . . . . . . . . . . . . . . . . . . . . . . . 97
Child Restraints Infants and Young Children . . . . . . . 60
Lower Anchors and Tethersfor Children . . . . . . . . . . . . . . . . . . . . . . . 65
Older Children . . . . . . . . . . . . . . . . . . . . . 59
Securing . . . . . . . . . . . . . . . . . . . . . . . . 72, 74
Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Circuit Breakers . . . . . . . . . . . . . . . . . . . . . 331
Cleaning Exterior Care . . . . . . . . . . . . . . . . . . . . . . 370
Interior Care . . . . . . . . . . . . . . . . . . . . . . 375
Climate Control Systems Dual Automatic . . . . . . . . . . . . . . . . . . . 196
Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Cluster, Instrument . . . . . . . . . . . . . . 88, 90
Collision Damage Repair . . . . . . . . . . . 406
Compartments Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
Compass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Competitive Driving Mode . . . . . . . . . 246
Composite Materials . . . . . . . . . . . . . . . . 218 Compressor Kit, Tire Sealant . . . . . . . 360
Connected Services
Connections . . . . . . . . . . . . . . . . . . . . . . . 419
Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . 420
Navigation . . . . . . . . . . . . . . . . . . . . . . . . . 418
Connections Connected Services . . . . . . . . . . . . . . . 419
Control Traction and ElectronicStability . . . . . . . . . . . . . . . . . . . . . . . . . . 239
Control of a Vehicle . . . . . . . . . . . . . . . . 204
Controls
Steering Wheel . . . . . . . . . . . . . . . . . . . . 137
Convex Mirrors . . . . . . . . . . . . . . . . . . . . . . 23
Coolant Engine Temperature Gauge . . . 94, 95
Engine Temperature Warning
Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196
Cooling System . . . . . . . . . . . . . . . . . . . . . 317
Cornering Lamps . . . . . . . . . . . . . . . . . . . 130
Courtesy Lamps . . . . . . . . . . . . . . . . . . . . . 130
Courtesy Transportation Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . 405
Coverage Explanations . . . . . . . . . . . . . 163
Cruise Control . . . . . . . . . . . . . . . . . . . . . . . 248
Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Cruise Control, Adaptive . . . . . . . . . . . 251 Cruise Control, Super . . . . . . . . . . . . . . . 260
Cupholders . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
Customer Assistance . . . . . . . . . . . . . . . 402
Offices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 401
Text Telephone (TTY) Users . . . . . 402
Customer Information Publications Ordering
Information . . . . . . . . . . . . . . . . . . . . . . 408
Customer Satisfaction Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . 399
Cybersecurity . . . . . . . . . . . . . . . . . . . . . . . . 410
D
Damage Repair, Collision . . . . . . . . . . . 406
Danger, Warning, and Caution . . . . . . . . 2
Data Collection Infotainment System . . . . . . . . . . . . . 412
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 412
Data Recorders, Event . . . . . . . . . . . . . . 411
Database Coverage Explanations . . . . . . . . . . . . . . . . . . . . . . 163
Daytime Running Lamps (DRL) . . . 128
Defensive Driving . . . . . . . . . . . . . . . . . . . 204
Delayed Locking . . . . . . . . . . . . . . . . . . . . . 17
Destination . . . . . . . . . . . . . . . . . . . . . . . . . . 155
Diagnostics Connected Services . . . . . . . . . . . . . . . 420
Differential, Limited-Slip . . . . . . . . . . . 248