2003 GMC SONOMA service

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

CAUTION: (Continued)
Even though the AIR BAG OFF switch is
designed to turn off the passenger’s frontal air
bag, no system is fail-safe, and no one can
guarantee that an air bag will not deploy under
some unusual circumstance, even though it is
turned off. General Motors therefore
recommends that rear-facing child restraints
be transported in vehicles with a rear seat that
will accommodate a rear-facing child restraint,
whenever possible.
If a forward-facing child restraint is suitable for
your child, always move the passenger seat as
far back as it will go.Although a rear seat is a safer place, you can secure a
forward-facing child restraint in the right front seat of
a crew cab.
{CAUTION:
If the air bag readiness light ever comes on
when you have turned off the air bag, it means
that something may be wrong with the air bag
system. The right front passenger’s air bag
could inflate even though the switch is off.
If this ever happens, don’t let anyone whom
the national government has identified as a
member of a passenger air bag risk group
sit in the right front passenger’s position
(for example, don’t secure a rear-facing child
restraint in your vehicle) until you have your
vehicle serviced. See″Air Bag Off Switch″in
the Index.
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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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The AIR BAG OFF light will come on to let you know
that the right front passenger’s air bag is off. The
right front passenger’s air bag will remain off until you
turn it back on again, and the AIR BAG OFF light
will stay on to remind you that the air bag is off.
{CAUTION:
If the air bag readiness light ever comes on
when you have turned off the air bag, it means
that something may be wrong with the air bag
system. The right front passenger’s air bag
could inate even though the switch is off.
If this ever happens, don’t let anyone whom
the national government has identied as a
member of a passenger air bag risk group
sit in the right front passenger’s position
(for example, don’t secure a rear-facing child
restraint in your vehicle) until you have your
vehicle serviced.To turn the right front passenger’s air bag on again,
insert your ignition key into the switch, push in,
and move the switch to the on position.
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Servicing Your Air Bag-Equipped
Vehicle
Air bags affect how your vehicle should be serviced.
There are parts of the air bag system in several places
around your vehicle. You don’t want the system to
inflate while someone is working on your vehicle.
Your dealer and the service manual have information
about servicing your vehicle and the air bag system.
To purchase a service manual, seeService Publications
Ordering Information on page 7-9.
{CAUTION:
For up to 10 minutes after the ignition key is
turned off and the battery is disconnected, an
air bag can still inate during improper service.
You can be injured if you are close to an air bag
when it inates. Avoid wires wrapped with
yellow tape or yellow connectors. They are
probably part of the air bag system. Be sure to
follow proper service procedures, and make
sure the person performing work for you is
qualied to do so.
The air bag system does not need regular maintenance.
Adding Equipment to Your Air
Bag-Equipped Vehicle
Q:If I add a push bumper or a bicycle rack to the
front of my vehicle, will it keep the air bags
from working properly?
A:As long as the push bumper or bicycle rack is
attached to your vehicle so that the vehicle’s
basic structure isn’t changed, it’s not likely to keep
the air bags from working properly in a crash.
Q:Is there anything I might add to the front of the
vehicle that could keep the air bags from
working properly?
A:Yes. If you add things that change your vehicle’s
frame, bumper system, front end sheet metal or
height, they may keep the air bag system
from working properly. Also, the air bag system
may not work properly if you relocate any of the air
bag sensors. If you have any questions about
this, you should contact Customer Assistance
before you modify your vehicle. The phone
numbers and addresses for Customer Assistance
are in Step Two of theCustomer Satisfaction
Procedure on page 7-2.
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Changes or modifications to this system by other than
an authorized service facility could void authorization
to use this equipment.
At times you may notice a decrease in range. This is
normal for any remote keyless entry system. If the
transmitter does not work or if you have to stand closer
to your vehicle for the transmitter to work, try this:
•Check the distance. You may be too far from your
vehicle. You may need to stand closer during
rainy or snowy weather.
•Check the location. Other vehicles or objects may be
blocking the signal. Take a few steps to the left or
right, hold the transmitter higher, and try again.
•Check to determine if battery replacement is
necessary. See“Battery Replacement”under
Remote Keyless Entry System Operation
on page 2-5.
•If you are still having trouble, see your dealer or
a qualified technician for service.
Remote Keyless Entry System
Operation
If your vehicle has this feature, you can lock and unlock
your doors from about 3 feet (1 m) up to 30 feet (9 m)
away using the remote keyless entry transmitter supplied
with your vehicle.
UNLOCK:When you
press UNLOCK, the
driver’s door will unlock
automatically, the parking
lamps willflash and the
interior lights will go on.
If you press UNLOCK again within three seconds, the
remaining doors will unlock, the parking lamps willflash
and the interior lights will go on.
LOCK:Press LOCK to lock all the doors. Press LOCK
again within three seconds and the horn will chirp.
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Remember, the theft-deterrent system won’t activate if
you lock the doors with a key or use the manual
door lock. It activates only if you use a power door lock
switch with the door open, or with the remote keyless
entry transmitter. You should also remember that
you can start your vehicle with the correct ignition key if
the alarm has been set off.
Here’s how to avoid setting off the alarm by accident:
•If you don’t want to activate the theft-deterrent
system, the vehicle should be locked with the door
keyafterthe doors are closed.
•Always unlock a door with a key, or use the remote
keyless entry transmitter. Unlocking a door any
other way will set off the alarm.
If you set off the alarm by accident, unlock any door
with the key. You can also turn off the alarm by pressing
UNLOCK on the remote keyless entry transmitter.
The alarm won’t stop if you try to unlock a door any
other way.
Testing the Alarm
The alarm can be tested by following these steps:
1. From inside the vehicle, lower the driver’s window
and open the driver’s door.
2. Activate the system by locking the doors with the
power door lock switch while the door is open, or
with the remote keyless entry transmitter.
3. Get out of the vehicle, close the door and wait for
the SECURITY light to go out.
4. Then reach in through the window, unlock the door
with the manual door lock and open the door. This
should set off the alarm.
If the alarm does not sound when it should but the
vehicle’s headlampsflash, check to see if the horn
works. The horn fuse may be blown. To replace
the fuse, seeFuses and Circuit Breakers on page 5-89.
If the alarm does not sound or the vehicle’s headlamps
do notflash, the vehicle should be serviced by an
authorized service center.
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Passlock®
Your vehicle is equipped with the
Passlock®theft-deterrent system.
Passlock
®is a passive theft-deterrent system.
Passlock®enables fuel if the ignition lock cylinder is
turned with a valid key. If a correct key is not used or the
ignition lock cylinder is tampered with, fuel is disabled.
During normal operation, the SECURITY light will
go off approximatelyfive seconds after the key is turned
to RUN.
If the engine stalls and the SECURITY lightflashes,
wait about 10 minutes until the light stopsflashing before
trying to restart the engine. Remember to release the
key from START as soon as the engine starts.
If the engine does not start after three tries, the vehicle
needs service.If the engine is running and the SECURITY message
comes on, you will be able to restart the engine if
you turn the engine off. However, your
Passlock
®system is not working properly and must be
serviced by your dealer. Your vehicle is not protected
by Passlock
®at this time. You may also want to check
the fuse. SeeFuses and Circuit Breakers on page 5-89.
See your dealer for service.
In an emergency, call the GM Roadside Assistance
Center. SeeRoadside Assistance Program on page 7-5.
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