2004 GMC SONOMA service

Seats and Restraint Systems........................... 1-1
Front Seats
............................................... 1-2
Rear Seats
............................................... 1-7
Safety Belts
.............................................. 1-8
Child Restraints
.......................................1-27
Air Bag System
.......................................1-46
Restraint System Check
............................1-53
Features and Controls..................................... 2-1
Keys
........................................................ 2-2
Doors and Locks
....................................... 2-7
Windows
.................................................2-12
Theft-Deterrent Systems
............................2-14
Starting and Operating Your Vehicle
...........2-16
Mirrors
....................................................2-31
Storage Areas
.........................................2-33
Sunroof
..................................................2-42
Instrument Panel............................................. 3-1
Instrument Panel Overview
.......................... 3-2
Climate Controls
......................................3-18
Warning Lights, Gages and Indicators
.........3-21
Audio System(s)
.......................................3-35Driving Your Vehicle....................................... 4-1
Your Driving, the Road, and Your Vehicle
..... 4-2
Towing
...................................................4-45
Service and Appearance Care.......................... 5-1
Service
..................................................... 5-3
Fuel
......................................................... 5-4
Checking Things Under the Hood
...............5-10
Rear Axle
...............................................5-46
Four-Wheel Drive
.....................................5-46
Front Axle
...............................................5-47
Bulb Replacement
....................................5-48
Windshield Wiper Blade Replacement
.........5-54
Tires
......................................................5-57
Appearance Care
.....................................5-86
Vehicle Identification
.................................5-94
Electrical System
......................................5-94
Capacities and Specifications
...................5-101
Maintenance Schedule..................................... 6-1
Maintenance Schedule
................................ 6-2
Customer Assistance and Information.............. 7-1
Customer Assistance and Information
........... 7-2
Reporting Safety Defects
...........................7-10
Index................................................................ 1
2004 GMC Sonoma Owner ManualM

{CAUTION:
When an air bag inates, 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
inates, 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.
1-51

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 7-11.
{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.
1-52

Remote Keyless Entry System
If equipped, the keyless entry system operates on a
radio frequency subject to Federal Communications
Commission (FCC) Rules and with Industry Canada.
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
1. This device may not cause interference, and
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
This device complies with RSS-210 of Industry Canada.
Operation is subject to the following two conditions:
1. This device may not cause interference, and
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
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.
2-4

3. Close all doors. The SECURITY light should go off
after approximately 30 seconds. The alarm is not
armed until the SECURITY light goes off.
If a door is opened without the key or the remote
keyless entry transmitter, the alarm will go off. Your
vehicle’s headlamps will flash and the horn will sound for
110 seconds, then will turn off to save the battery
power.
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 headlamps flash, check to see if the horn
works. The horn fuse may be blown. To replace
the fuse, seeFuses and Circuit Breakers on page 5-95.
If the alarm does not sound or the vehicle’s headlamps
do not flash, the vehicle should be serviced by an
authorized service center.
2-15

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 approximately five seconds after the key is turned
to RUN.
If the engine stalls and the SECURITY light flashes,
wait about 10 minutes until the light stops flashing 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 5-95.
See your dealer for service.
In an emergency, call the GM Roadside Assistance
Center. SeeRoadside Assistance Program on page 7-6.
Starting and Operating Your
Vehicle
New Vehicle Break-In
Notice:Your vehicle does not need an elaborate
“break-in.” But it will perform better in the long run
if you follow these guidelines:
Keep your speed at 55 mph (88 km/h) or less for
the rst 500 miles (805 km).
Do not drive at any one speed — fast or
slow — for the rst 500 miles (805 km). Do not
make full-throttle starts.
Avoid making hard stops for the rst 200 miles
(322 km) or so. During this time your new
brake linings are not yet broken in. Hard stops
with new linings can mean premature wear
and earlier replacement. Follow this breaking-in
guideline every time you get new brake
linings.
Do not tow a trailer during break-in. SeeTowing
a Trailer on page 4-55for more information.
2-16

Ignition Positions
With the key in the ignition, you can turn it to five
different positions.
Notice:Lengthy operation of features such as
the radio in the accessory ignition position may
drain the battery and prevent your vehicle from
starting. Do not operate your vehicle in the
accessory ignition position for a long period
of time.A (ACCESSORY):This position lets you use things like
the radio and the windshield wipers when the engine
is off. Push in the key and turn it toward you. Your
steering wheel will remain locked, just as it was before
you inserted the key.
Notice:Using a tool to force the key from the
ignition switch could cause damage or break the key.
Use the correct key and turn the key only with your
hand. Make sure the key is all the way in. If it is, turn
the steering wheel left and right while you turn the
key hard. If none of this works, then your vehicle
needs service.
B (LOCK):This position locks your ignition when
the key is removed. The steering wheel locks
when equipped with a manual transmission. It’s a
theft-deterrent feature. You will only be able to remove
your key when the ignition is turned to LOCK.
C (OFF):This position lets you turn off the engine
but still turn the steering wheel. Use OFF if you must
have your vehicle in motion while the engine is off
(for example, if your vehicle is being towed).
D (RUN):This is the position for driving.
E (START):This position starts your engine.
2-17

Transfer Case
The transfer case buttons
are to the right of the
steering wheel on
the instrument panel.
Use these buttons to shift into and out of
four-wheel-drive. You can choose among three driving
settings:
2HI (Two-Wheel Drive High):This setting is for driving
in most street and highway situations. Your front axle
is not engaged in two-wheel drive. When this light
is turned on, it is about one-half as bright as the others.4HI (Four-Wheel Drive High):This setting engages
your front axle to help drive your vehicle. Use 4HI when
you need extra traction, such as on snowy or icy
roads, or in most off-road situations.
4LO (Four-Wheel Drive Low):You may never need
4LO. This setting also engages your front axle to
give you extra traction. It sends the maximum power to
all four wheels. You might choose 4LO if you were
driving off-road in sand, mud or deep snow and climbing
or descending steep hills.
Indicator lights in the buttons show you which setting
you are in. The indicator lights will come on briefly when
you turn on the ignition and one will stay on. If the
lights do not come on, you should take your vehicle in
for service. An indicator light will flash while shifting.
It will remain illuminated when the shift is completed.
Shifting from 2HI to 4HI
Press and release the 4HI button. This can be done at
any speed, and the front axle will lock automatically.
Shifting from 4HI to 2HI
Press and release the 2HI button. This can be done at
any speed, and the front axle will unlock automatically.
2-23