2002 GMC SIERRA service

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How does 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 vents in the deflated air bags. Air bag
inflation doesn't prevent the driver from seeing or from
being able to steer the vehicle, nor does it stop people
from leaving the vehicle.
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 door.
In many crashes severe enough to inflate an air bag,
windshields are broken by vehicle deformation.
Additional windshield breakage may also occur from the
right front passenger air bag.

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.

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Your vehicle is equipped with a crash sensing and
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. The module also records speed,
engine rpm, brake and throttle data.

Let only qualified technicians work on your air bag
system. Improper service can mean that your 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.
Air Bag Off Switch
Your vehicle has a switch on the instrument panel
that you can use to turn off the right front passenger's
air bag.

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To turn off the right front passenger's air bag, insert
your ignition key into the switch, push in, and move the
switch to AIR BAG OFF.
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 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 the right
front passenger's seat) until you have your
vehicle serviced.

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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.
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, see ªService and Owner
Publicationsº in the Index.
CAUTION:
For up to 10 minutes after the ignition key is
turned off and the battery is disconnected, an air
bag can still inflate during improper service. You
can be injured if you are close to an air bag when
it inflates. 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 qualified to do so.
The air bag system does not need regular maintenance.

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CAUTION:
A child in a rear-facing child restraint can be
seriously injured or killed if the right front
passenger's air bag inflates. This is because the
back of the rear
-facing child restraint would be
very close to the inflating air bag. Be sure to turn
off the air bag before using a rear
-facing child
restraint in the right front seat position. 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.
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 the right
front passenger's seat) until you have your
vehicle serviced. See ªAir Bag Off Switchº in
the Index.

2-7 Power Door Locks
Press the raised side of the
switch, marked L on either
front door, to lock all the
doors at once.
Press the recessed side of the switch marked U to unlock
all the doors at once.
The power door locks will operate at any time without
the ignition being on.
The power door locks can be programmed to
automatically lock and unlock depending on the settings
you have chosen in the secondary information center.
See ªSecondary Information Centerº in the Index for
more information.
Operating the power locks may interact with the
theft
-deterrent system. See ªContent Theft-Deterrentº
in the Index.
Keyless Entry System
You can lock and unlock your doors from about 3 feet
(1 m) up to 100 feet (30 m) away using the remote
keyless entry transmitter supplied with your vehicle.
Your 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 harmful interference, and
(2) this device must accept any interference received,
including interference that may cause undesired operation.
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.

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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 the instructions that follow.

If you're still having trouble, see your dealer or a
qualified technician for service.Operation
UNLOCK: Pressing this button once will unlock the
driver's door. The interior lamps will come on. Pressing
UNLOCK again within three seconds will cause the
remaining doors to unlock.
You can choose different feedback options for each
press of the UNLOCK button. See ªSecondary
Information Centerº in the Index for more information.
LOCK: Pressing this button once will lock all of the
doors. You can choose different feedback options for
each press of the LOCK button. See ªSecondary
Information Centerº in the Index for more information.
Operating the keyless entry transmitter may interact
with the theft
-deterrent system. See ªContent-Theft
Deterrentº and ªSecondary Information Centerº in the
Index for more information.
Remote Panic Alarm
When the horn symbol on the keyless entry transmitter
is pressed, the horn will sound and the headlamps and
taillamps will flash for up to 30 seconds. This can be
turned off by pressing the horn button again, waiting for
30 seconds, or starting the vehicle.

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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.
If the engine stalls and the SECURITY message flashes,
wait until the message stops flashing before trying to
restart the engine. Remember to release the key from
START as soon as the engine starts.
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 (see ªFuses
and Circuit Breakersº in the Index). See your dealer
for service.
In an emergency, call the GMC Roadside Assistance
Center. See ªRoadside Assistanceº in the Index.
New Vehicle ªBreak-Inº
NOTICE:
Your vehicle doesn't need an elaborate
ªbreak
-in.º 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 first 500 miles (805 km).

Don't drive at any one speed
-- fast or
slow
-- for the first 500 miles (805 km).
Don't make full
-throttle starts.

Avoid making hard stops for the first
200 miles (322 km) or so. During this time
your new brake linings aren't 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.

Don't tow a trailer during break
-in.
See ªTowing a Trailerº in the Index for
more information.