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
Page 10 of 424
Power Seats
If your vehicle has this feature, there will be a control on
the outboard side of the front seat(s).
Horizontal Control:Raise or lower the front of the seat
by raising or lowering the forward edge of the control.
Raise or lower the rear of the seat by raising or lowering
the rear edge of the control. Move the seat forward or
rearward by moving the whole control toward the front or
the rear of the vehicle.Moving the whole control up or down raises or lowers
the whole seat.
Vertical Control:Move the reclining front seatback
forward or rearward by moving the control toward
the front or rear of the vehicle.
Manual Lumbar
If your vehicle has this
feature, there will be a
knob located on the
outboard side of the
driver’s seat.
Turn the knob counterclockwise to increase lumbar
support and clockwise to decrease lumbar support.
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{CAUTION:
Never do this.
Here two children are wearing the same belt.
The belt can’t properly spread the impact
forces. In a crash, the two children can be
crushed together and seriously injured. A belt
must be used by only one person at a time.
Q:What if a child is wearing a lap-shoulder belt,
but the child is so small that the shoulder belt
is very close to the child’s face or neck?
A:Move the child toward the center of the vehicle,
but be sure that the shoulder belt still is on the
child’s shoulder, so that in a crash the child’s upper
body would have the restraint that belts provide.
If the child is so small that the shoulder belt is still
very close to the child’s face or neck, you might
want to place the child in a seat that has a lap belt,
if your vehicle has one.
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Page 42 of 424
Child Restraint Systems
An infant car bed (A), a special bed made for use in a
motor vehicle, is an infant restraint system designed
to restrain or position a child on a continuousflat
surface. Make sure that the infant’s head rests toward
the center of the vehicle.A rear-facing infant seat (B) provides restraint with the
seating surface against the back of the infant. The
harness system holds the infant in place and, in a crash,
acts to keep the infant positioned in the restraint.
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Page 64 of 424

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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Page 82 of 424

No doors lock/None of the doors unlock:Press the
lock side of the power door lock switch twice. This
turns off the automatic lock feature. This is the factory
setting.
For more information, see your dealer.
If your vehicle has an automatic transmission it will be
programmed to have all the doors lock automatically
when the shift lever is moved out of PARK (P). All the
doors will unlock when the shift lever is moved back into
PARK (P).
On a manual transmission, all doors will lock when the
vehicle speed is greater than 15 mph (24 km/h).
The doors will unlock when the key is removed from the
ignition.
The following instructions detail how to program your
door locks. Choose one of the programming options
before entering the programming mode.To enter the program mode, do the following:
1. Begin with the ignition in OFF. Then pull the turn
signal/multifunction lever all the way toward you
and hold it while you perform the next step.
2. Turn your key to RUN and OFF twice. Then, with
the key in OFF, release the turn signal/multifunction
lever. Once you do this, you will hear the lock
switch lock and unlock.
3. You are now ready to program the automatic door
locks. Select one of the previous four programming
options and follow the instructions. You will have
30 seconds to begin programming. If you exceed
the 30 second limit, the locks will automatically lock
and unlock to indicate you have left the program
mode. If this occurs, repeat the procedure beginning
with Step 1. You can exit the program mode any
time by turning the ignition to RUN. The locks
will automatically lock and unlock to indicate you
are leaving the program mode. If the lock/unlock
switches are not pressed while in the programming
mode, the auto lock/unlock setting will not be
modified.
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Page 85 of 424
3. With the tailgate halfway down, pull the tailgate
toward you at the left side and then move the
tailgate to the left to release the right side.
Reverse the procedure to reinstall the tailgate. Make
sure it is secure.
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Page 88 of 424
Swing-Out Windows
To open a rear swing–out
window, pull the latch
toward the front of
the vehicle and then push
the latch out and
rearward.
When you close the window, be sure the latch engages.
Sliding Rear Window
If your vehicle has this feature, squeeze the latch in the
center of the window and slide the glass to open it.
When you close the window, be sure the latch is
engaged.
Sun Visors
To block out glare, you can pull the visor down. You
can also swing the visor from side-to-side.
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