GMC SIERRA DENALI 2003 Repair Manual

5. Pull the rest of the shoulder belt all the way out of
the retractor to set the lock. 6.
7.
To tighten the
belt, feed the shoulder belt back into
the retractor while you push down on the child
restraint.
If you’re using a forward-facing child
restraint, you may find it helpful to use your knee to
push down on the child restraint as you tighten the
belt. You should not be able to pull more of the belt
out of the retractor once the lock has been set.
Push and pull the child restraint in different
directions to be sure it is secure.
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if your vehicle has the passenger sensing system and
you’re using a rear-facing child restraint in this seat,
check to be sure the right front passenger’s frontal air
bag is
off before you begin to drive. If the air bag
has been turned
off, the off indicator wiii iight and stay
lit in the rearview mirror.
If the on indicator is lit, the passenger’s frontal air bag
has not been turned
off by the passenger sensing
system. If this ever happens, turn the vehicle
off,
unbuckle the safety belt and perform the steps to install
the rear-facing restraint again. After restarting the
vehicle,
if the air bag still doesn’t turn off, install the
infant restraint in a rear seat position of the vehicle or
check to make sure the AIR
BAG OFF switch has been
turned to
off. See Air Bag Off Switch on page 1-64
and Passenger Sensing System on page 1-68.
If the air bag ON indicator comes on when you
have a rear-facing child restraint installed in
the right front passenger’s seat, it means that
the passenger sensing system has not turned
off the passenger’s frontal air bag. 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. Don’t use a
rear-facing child restraint
in the right front
passenger’s seat unless the air bag
is off.
To remove the child restraint, just unbuckle the vehicle’s
safety belt and let it go back all the way. The safety
belt will remove freely again and be ready to work for an
adult or larger child passenger.
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If you were using a rear-facing child restraint and had
turned the air bag
off with the switch, remember to turn
on the right front passenger’s air bag when
you
remove the rear-facing child restraint from the vehicle
unless the person who will be sitting there is
a member
of
a passenger air bag risk group. See Air Bag Off
Switch on page 1-64.
If the r - ror ,)asse _er’s a lag is turned
off for a person who isn’t in a risk group
identified by the national government, that
person won’t have the extra protection
of an
air bag. In a crash, the air bag wouldn’t be able
to inflate and help protect the person sitting
there. Don’t turn
off the passenger’s air bag
unless the person sitting there is in a risk
group. See “Air Bag
Off Switch” in the Index.
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Air Bag Systems
This part explains the air bag system.
Your vehicle has air bags
- one air bag for the driver
and another air bag for the right front passenger.
Frontal air bags are designed
to help reduce the risk of
injury from the force of an inflating frontal air bag.
But these air bags must inflate very quickly to do their
job and comply with federal regulations.
Here are the most important things to know about the
air bag systems:
You can be severely injured or killed in a crash
if you aren’t wearing your safety belt
- even if
you have air bags. Wearing your safety belt
during a crash helps reduce your chance of hitting things inside the vehicle or being
ejected from
it. Air bags are designed to work
with safety belts, but don’t replace them. Air
bags are designed to deploy only in moderate
CAUTION: (Continued) to
sei ‘e frontal and near frontal crashes.
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.
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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. 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”.
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r
There is an air bag
readiness light on the
instrument panel cluster,
which shows the air
bag
symbol.
Where Are the Air Bags?
The system checks the air bag electrical system for
malfunctions. The light tells you
if there is an electrical
problem. See
Air Bag Readiness Light on page 3-27
for more information.
The driver’s air bag is in the middle of the steering
wheel.
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If something is between an occupant and an
air bag, the bag might not inflate properly or
it
might force the object into that person causing
severe injury or even death. The path of an
inflating air bag must be kept clear. Don’t put
anything between an occupant and an air bag,
and don’t attach or put anything on the
steering wheel hub or on or near any other air
bag covering.
The right front passenger’s air bag is in the instrument
panel
on the passenger’s side.
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When Should an Air Bag Inflate?
An air bag is designed to inflate in a moderate to severe
frontal, or near-frontal crash. The air bag will inflate
only
if the impact speed is above the system’s designed
“threshold level.”
In addition, your vehicle has “dual stage” frontal air
bags, which adjust the amount of restraint according to
crash severity. For moderate frontal impacts, these
air bags inflate at a level less than full deployment. For
more severe frontal impacts, full deployment occurs.
If the front of your vehicle goes straight into a wall that
doesn’t move or deform, the threshold level for the
reduced deployment is about
10 to 16 mph
(16 to 25 km/h), and the threshold level for a full
deployment is about
20 to 25 mph (32 to 40 km/h). The
threshold level can vary, however, with specific
vehicle design,
so that it can be somewhat above or
below this range.
If your vehicle strikes something that will move or
deform, such as a parked car, the threshold level will be
higher. The air bag is not designed to inflate in
rollovers, rear impacts, or in many side impacts because
inflation would not help the occupant.
In any particular crash, no one can say whether an air
bag should have inflated simply because of the damage
to a vehicle or because of what the repair costs were. Inflation
is determined by the angle of the impact and
how quickly the vehicle slows down in frontal or
near-frontal impacts.
The air bag system
is designed to work properly under
a wide range
of conditions, including off-road usage.
Observe safe driving speeds, especially on rough
terrain.
As always, wear your safety belt. See “Off-Road
Driving” in the Index for more tips on off-road driving.
Seat Position Sensors
Vehicle’s with dual stage air bags are also equipped
with special sensors which enable the sensing system to
monitor the position of both the driver and passenger
front seats. The seat position sensor provides
information which is used to determine
if the air bags
should deploy at a reduced level or at full depoyment.
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.
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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 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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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.
In many crashes severe enough to inflate the 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.
Your vehicle is equipped with electronic frontal
sensors which help the sensing system distinguish
between a moderate and a more severe frontal
impact. Your vehicle is also equipped with a crash
sensing and diagnostic module, which records
information about the frontal air bag system. The
module records information about the readiness of
the system and when the system commands
are bag inflation. It records the status of the driver’s
safety belt usage in a crash in which the air bag
deploys or a crash in which the air bag nearly
deploys. The module also records speed, engine
RPM, brake and throttle data.
Let only qualified technicians work on your air bag
systems. 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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