Page 1 of 424

Seats and Restraint Systems........................... 1-1
Front Seats
............................................... 1-3
Rear Seats
............................................... 1-9
Safety Belts
.............................................1-10
Child Restraints
.......................................1-30
Air Bag System
.......................................1-54
Restraint System Check
............................1-64
Features and Controls..................................... 2-1
Keys
........................................................ 2-3
Doors and Locks
....................................... 2-8
Windows
.................................................2-14
Theft-Deterrent Systems
............................2-17
Starting and Operating Your Vehicle
...........2-20
Mirrors
....................................................2-39
Storage Areas
.........................................2-41
Sunroof
..................................................2-52
Vehicle Personalization
.............................2-54
Instrument Panel............................................. 3-1
Instrument Panel Overview
.......................... 3-2
Climate Controls
......................................3-17
Warning Lights, Gages and Indicators
.........3-20
Audio System(s)
.......................................3-36
Driving Your Vehicle....................................... 4-1
Your Driving, the Road, and Your Vehicle
..... 4-2
Towing
...................................................4-42Service and Appearance Care.......................... 5-1
Service
..................................................... 5-3
Fuel
......................................................... 5-4
Checking Things Under the Hood
................. 5-8
Rear Axle
...............................................5-47
Four-Wheel Drive
.....................................5-48
Front Axle
...............................................5-49
Bulb Replacement
....................................5-50
Windshield Wiper Blade Replacement
.........5-56
Tires
......................................................5-58
Appearance Care
.....................................5-79
Vehicle Identification
.................................5-87
Electrical System
......................................5-88
Capacities and Specifications
.....................5-94
Normal Maintenance Replacement Parts
......5-96
Maintenance Schedule..................................... 6-1
Maintenance Schedule
................................ 6-2
Customer Assistance Information.................... 7-1
Customer Assistance Information
.................. 7-2
Reporting Safety Defects
............................ 7-8
Index................................................................ 1
2003 GMC Sonoma Owner ManualM
2003 - Sonoma Owner Manual
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Vehicle Damage Warnings
Also, in this book you willfind these notices:
Notice:These mean there is something that could
damage your vehicle.
A notice will tell you about something that can damage
your vehicle. Many times, this damage would not be
covered by your warranty, and it could be costly. But the
notice will tell you what to do to help avoid the
damage.
When you read other manuals, you might see CAUTION
and NOTICE warnings in different colors or in different
words.
You’ll also see warning labels on your vehicle. They use
the same words, CAUTION or NOTICE.
Vehicle Symbols
Your vehicle has components and labels that use
symbols instead of text. Symbols, used on your vehicle,
are shown along with the text describing the operation
or information relating to a specific component, control,
message, gage or indicator.
If you need helpfiguring out a specificnameofa
component, gage or indicator, reference the following
topics:
•Seats and Restraint Systems in Section 1
•Features and Controls in Section 2
•Instrument Panel Overview in Section 3
•Climate Controls in Section 3
•Warning Lights, Gages and Indicators in Section 3
•Audio System(s) in Section 3
•Engine Compartment Overview in Section 5
iv
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or the instrument panel...
or the safety belts!
With safety belts, you slow down as the vehicle does.
You get more time to stop. You stop over more distance,
and your strongest bones take the forces. That’s why
safety belts make such good sense.
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Securing a Child Restraint in a
Center Seat Position
Don’t use child restraints in these positions.
The restraints won’t work properly.
Securing a Child Restraint in the
Right Front Seat Position
If your child restraint is equipped with the LATCH
system, seeLower Anchorages and Top Tethers for
Children (LATCH System) on page 1-44.
Your vehicle has a passenger air bag. If your vehicle is
a regular cab pickup or an extended cab pickup,
there’s a switch on the instrument panel that you can
use to turn off the right front passenger’s air bag
when you want to secure a rear-facing child restraint at
the right front passenger’s position. SeeAir Bag Off
Switch on page 1-60for more on this, including
important safety information.
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CAUTION: (Continued)
They aren’t designed to inflate at all in rollover,
rear or low-speed frontal crashes, or in many
side crashes. And, for some unrestrained
occupants, air bags may provide less
protection in frontal crashes than more
forceful air bags have provided in the past.
Everyone in your vehicle should wear a safety
belt properly — whether or not there’s an air
bag for that person.
{CAUTION:
Air bags inflate with great force, faster than the
blink of an eye. If you’re too close to an
inflating air bag, as you would be if you were
leaning forward, it could seriously injure you.
Safety belts help keep you in position before
and during a crash. Always wear your safety
belt, even with air bags. The driver should sit
as far back as possible while still maintaining
control of the vehicle.
{CAUTION:
Anyone who is up against, or very close to,
any air bag when it inflates can be seriously
injured or killed. Air bags plus lap-shoulder
belts offer the best protection for adults, but
not for young children and infants. Neither the
vehicle’s safety belt system nor its air bag
system is designed for them. Young children
and infants need the protection that a child
restraint system can provide. Always secure
children properly in your vehicle. To read how,
see the parts of this manual called “Older
Children” and “Infants and Young Children”.
There is a air bag
readiness light on the
instrument panel, which
shows the air bag symbol.
The system checks the air bag electrical system for
malfunctions. The light tells you if there is an electrical
problem. SeeAir Bag Readiness Light on page 3-24.
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Where Are the Air Bags?
The driver’s air bag is in the middle of the steering
wheel.The right front passenger’s air bag is in the instrument
panel on the passenger’s side.
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What Makes an Air Bag Inflate?
In an impact of sufficient severity, the air bag sensing
system detects that the vehicle is in a crash. The
sensing system triggers a release of gas from the
inflator, which inflates the air bag. The inflator, air bag,
and related hardware are all part of the air bag
modules inside the steering wheel and in the instrument
panel in front of the right front passenger.
HowDoes an Air Bag Restrain?
In moderate to severe frontal or near-frontal collisions,
even belted occupants can contact the steering wheel or
the instrument panel. Air bags supplement the
protection provided by safety belts. Air bags distribute
the force of the impact more evenly over the occupant’s
upper body, stopping the occupant more gradually.
But air bags would not help you in many types of
collisions, including rollovers, rear impacts and many
side impacts, primarily because an occupant’s motion is
not toward those air bags. Air bags should never be
regarded as anything more than a supplement to safety
belts, and then only in moderate to severe frontal or
near-frontal collisions.
What Will You See After an Air Bag
Inflates?
After an air bag inflates, it quickly deflates, so quickly that
some people may not even realize the air bag inflated.
Some components of the air bag module—the steering
wheel hub for the driver’s air bag, or the instrument panel
for the right front passenger’s bag—will be hot for a
short time. The parts of the bag that come into contact
with you may be warm, but not too hot to touch. There will
be some smoke and dust coming from the vents in the
deflated air bags. Air bag inflation doesn’t prevent the
driver from seeing or being able to steer the vehicle,
nor does it stop people from leaving the vehicle.
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{CAUTION:
When an air bag inflates, there is dust in the
air. This dust could cause breathing problems
for people with a history of asthma or other
breathing trouble. To avoid this, everyone in
the vehicle should get out as soon as it is safe
to do so. If you have breathing problems but
can’t get out of the vehicle after an air bag
inflates, then get fresh air by opening a
window or a door. If you experience breathing
problems following an air bag deployment,
you should seek medical attention.
•Air bags are designed to inflate only once. After
they inflate, you’ll need some new parts for your
air bag system. If you don’t get them, the air
bag system won’t be there to help protect you in
another crash. A new system will include air
bag modules and possibly other parts. The service
manual for your vehicle covers the need to
replace other parts.
•Your vehicle is equipped with a diagnostic module,
which records information about the air bag
system. The module records information about the
readiness of the system, when the system
commands air bag inflation and driver’s safety belt
usage at deployment.
•Let only qualified technicians work on your air bag
system. Improper service can mean that an air
bag system won’t work properly. See your dealer
for service.
Notice:If you damage the covering for the driver’s
or the right front passenger’s air bag, the bag
may not work properly. You may have to replace the
air bag module in the steering wheel or both the
air bag module and the instrument panel for
the right front passenger’s air bag. Do not open or
break the air bag coverings.
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