2004 GMC SIERRA steering

Where Are the Air Bags?
The driver's air bag is in the middle of the steering
wheel.The right front passenger's air bag is in the instrument
panel on the passenger's side.
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{CAUTION:
If something is between an occupant and an
air bag, the bag might not in¯ate properly or it
might force the object into that person causing
severe injury or even death. The path of an
in¯ating 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.
When Should an Air Bag In¯ate?
An air bag is designed to in¯ate in a moderate to severe
frontal, or near-frontal crash. The air bag will in¯ate
only if the impact speed is above the system's designed
ªthreshold level.º
In any particular crash, no one can say whether an air
bag should have in¯ated simply because of the damage
to a vehicle or because of what the repair costs were.
In¯ation 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 with Your Four-Wheel-Drive Vehicle on
page 4-20
for more tips on off-road driving.
Single Stage vs. Dual Stage Air Bags
Depending on the weight of your vehicle you will
have either ªSingle Stage Air Bagsº or ªDual Stage Air
Bagsº. Vehicles that have a passenger sensing
system also have dual stage air bags. If the rearview
mirror in your vehicle has a passenger air bag
status indicator printed on it, your vehicle has the
passenger sensing system and therefore, it has dual
stage air bags. If the rearview mirror in your vehicle does
not have a passenger air bag status indicator printed
on it, then your vehicle does not have the passenger
sensing system and it has single stage air bags.
See
Passenger Air Bag Status Indicator on page 3-40orPassenger Sensing System on page 1-81.
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Dual Stage Air Bags
If your vehicle has frontal air bags with dual stage
deployment, the amount of restraint will adjust according
to crash severity. For moderate frontal impacts, these
air bags in¯ate 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
does not 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 speci®c
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 in¯ate in
rollovers, rear impacts, or in many side impacts because
in¯ation would not help the occupant.
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 deployment.
Single Stage Air Bags
If your vehicle has frontal air bags with single stage
deployment and your vehicle goes straight into a wall
that does not move or deform, the threshold level
is about 13 to 16 mph (20 to 25 km/h). The threshold
level can vary, however, with speci®c 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 in¯ate in
rollovers, rear impacts, or in many side impacts because
in¯ation would not help the occupant.
What Makes an Air Bag In¯ate?
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
in¯ator, which in¯ates the air bag. The in¯ator, 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
In¯ates?
After an air bag in¯ates, it quickly de¯ates, so quickly that
some people may not even realize the air bag in¯ated.
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 thede¯ated air bags. Air bag in¯ation does not prevent the
driver from seeing or being able to steer the vehicle, nor
does it stop people from leaving the vehicle.
{CAUTION:
When an air bag in¯ates, 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
in¯ates, 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.
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In many crashes severe enough to in¯ate 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 in¯ate only once. After
they in¯ate, you will need some new parts for
your air bag system. If you do not get them, the air
bag system will not 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 air
bag in¯ation. 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 quali®ed technicians work on your air bag
systems. Improper service can mean that an air
bag system will not 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
Regular Cab and Extended Cab Models
If your vehicle is a regular cab model or an extended cab
model, it 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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Ignition Positions
With the key in the ignition switch, you can turn it to four
different positions.
A (LOCK):This position locks your ignition when the
key is removed. The steering locks when equipped with
a manual transmission. It is a theft-deterrent feature.
You will only be able to remove your key when the
ignition is turned to LOCK
B (ACCESSORY):This position allows you to use
things like the radio, power windows and the windshield
wipers when the engine is off.{CAUTION:
On manual transmission vehicles, turning the
key to LOCK will lock the steering column and
result in a loss of ability to steer the vehicle.
This could cause a collision. If you need to
turn the engine off while the vehicle is moving,
turn the key only to OFF. Do not press the key
release button while the vehicle is moving.
Notice:If your key seems stuck in LOCK and you
can not turn it, be sure you are using the correct
key; if so, is it all the way in? Turn the key only with
your hand. Using a tool to force it could break the
key or the ignition switch. If none of these works,
then your vehicle needs service.
C (RUN):This is the position for driving.
D (START):This position starts your engine.
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Engine Coolant Heater
In very cold weather, 0ÉF
(-18ÉC) or colder, the
engine coolant heater can
help. You'll get easier
starting and better
fuel economy during
engine warm-up. Usually,
the coolant heater
should be plugged in a
minimum of four hours
prior to starting your
vehicle.
At temperatures above 32ÉF (0ÉC), use of the coolant
heater is not required.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord. The
cord is located on the driver's side of the engine
compartment, near the power steering ¯uid
reservoir. If you have a diesel engine, refer to
diesel supplement for location.
3. Plug it into a normal, grounded 110-volt AC outlet.
{CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the
wrong kind of extension cord could overheat
and cause a ®re. You could be seriously
injured. Plug the cord into a properly grounded
three-prong 110-volt AC outlet. If the cord will
not reach, use a heavy-duty three-prong
extension cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and
store the cord as it was before to keep it away
from moving engine parts. If you don't, it could be
damaged.
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OnStaržSteering Wheel Controls
g
: If your vehicle is
equipped with the steering
wheel control buttons
you can use them
to interact with the OnStar
ž
system.
See the OnStar
žmanual provided with your vehicle for
more information.
Storage Areas
Your vehicle includes a number of storage
compartments for storage of often-used items.
Some vehicles have storage areas in the instrument
panel.
Some models have a storage pocket on each of the
front doors.
Some vehicles have a storage area behind the seat.
Glove Box
To open your glove box, pull the lever upward and pull
the door downward.
Cupholder(s)
Your vehicle may have cupholders located in the front
console, or in the fold-down armrest.
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