instrument panel GMC SIERRA 2004 User Guide

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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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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The passenger sensing system will turn off the right
front passenger's frontal air bag under certain
conditions. The driver's air bag is not part of the
passenger sensing system. In addition to the passenger
sensing system, your vehicle also has an air bag off
switch located on the instrument panel.The passenger sensing system works with sensors that
are part of the right front passenger's seat and safety
belt. The sensors are designed to detect the presence of
a properly seated occupant and determine if the
passenger's frontal air bag should be enabled (may
in¯ate) or not.
Accident statistics show that children are safer if they
are restrained in the rear rather than the front seat.
General Motors recommends that child restraints
be secured in a rear seat, including an infant riding in a
rear-facing infant seat, a child riding in a forward-facing
child seat and an older child riding in a booster seat.
Never put a child in a rear-facing child restraint in
the right front passenger seat unless the passenger air
bag status indicator shows off. Never put a rear-facing
child restraint in the right front passenger seat unless the
air bag is off. Passenger Air Bag Status Indicator ± United States
Passenger Air Bag
Status Indicator
-Canada
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{CAUTION:
If the air bag readiness light in the instrument
panel cluster ever comes on and stays on, it
means that something may be wrong with the
air bag system. If this ever happens, have the
CAUTION: (Continued)
CAUTION: (Continued)
vehicle serviced promptly, because an
adult-size person sitting in the right front
passenger's seat may not have the protection
of the frontal air bag. See ªAir Bag Readiness
Lightº in the Index for more on this, including
important safety information.
Aftermarket equipment, such as seat covers, can affect
how well the passenger sensing system operates.
You may want to consider not using seat covers or other
aftermarket equipment if your vehicle has the passenger
sensing system. See
Adding Equipment to Your Air
Bag-Equipped Vehicle on page 1-86for more
information about modi®cations that can affect how the
system operates.
{CAUTION:
Stowing of articles under the passenger's seat
or between the passenger's seat cushion and
seatback may interfere with the proper
operation of the passenger sensing system.
1-85

How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature, the
kind of oil you have, and some other things. Instead
of trying to list everything here, we ask that you contact
your dealer in the area where you'll be parking your
vehicle. The dealer can give you the best advice for that
particular area.
Automatic Transmission Operation
If your vehicle is equipped with an automatic
transmission, it features an electronic shift position
indicator within the instrument panel cluster. This display
must be powered anytime the shift lever is capable of
being moved out of PARK (P). See
Fuses and
Circuit Breakers on page 5-126.
There are several different positions for your shift lever.
PARK (P):This position locks your rear wheels. It's
the best position to use when you start your engine
because your vehicle can't move easily. If your vehicle
is equipped with the Allison
žTransmission, use
PARK (P) for stationary operation of the Power Takeoff
(PTO), if equipped.
{CAUTION:
It is dangerous to get out of your vehicle if the
shift lever is not fully in PARK (P) with the
parking brake ®rmly set. Your vehicle can roll.
Do not leave your vehicle when the engine is
running unless you have to. If you have left the
engine running, the vehicle can move
suddenly. You or others could be injured. To
be sure your vehicle will not move, even when
you are on fairly level ground, always set your
parking brake and move the shift lever to
PARK (P). See
Shifting Into Park (P) on
page 2-49
. If you are pulling a trailer, see
Towing a Trailer on page 4-70.
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Tow/Haul Mode
(Automatic Transmission)
Your vehicle may be equipped with a Tow/Haul mode.
The selector button is located on the end of the
column shift lever. You can use this feature to assist
when towing or hauling a heavy load. Turn Tow/Haul on
and off by pressing the button until the Tow/Haul
indicator light illuminates on the instrument panel. See
ªTow/Haul Mode²under
Towing a Trailer on page 4-70for more information.
Overdrive Disable
(Allison Transmissionž)
If your vehicle has an Allison Transmissionžyou may
have the overdrive disable feature. The overdrive disable
feature prevents the transmission from shifting into
®fth (5) gear. The selector button is located on the end of
the column shift lever. You can turn overdrive disable on
and off by pressing and holding the button at the end of
the column shift lever until the indicator light, on the
instrument panel, illuminates.
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Shifting In or Out of 4LO
Notice:Shifting the transfer case into 4LO while
moving at speeds faster than 3 mph (5 km/h)
may cause premature wear to the transfer case, and
may cause the gears to grind. To avoid causing
premature wear, and grinding the gears, do not shift
the transfer case into 4LO while the vehicle is
moving faster than 3 mph (5 km/h).
Shifts into 4LO can be made with the vehicle at a stop,
or while slowly rolling about 1 to 3 mph (2 to 5 km/h).
·Shift the automatic transmission into NEUTRAL
(N), or with a manual transmission, press the
clutch pedal, or shift into NEUTRAL (N).
·Shift the transfer case shift lever in one continuous
motion into the 4LO position.
·When in 4LO do not drive faster than 45 mph.
This will reduce wear and extend the life of
your transfer case.
Shifting In or Out of NEUTRAL
1. With the vehicle running and the engine at an idle
set the parking brake.
2. Place the transmission into NEUTRAL (N).
Shift the transfer case in one continuous motion into or
out of the NEUTRAL (N) position.
Automatic Transfer Case
The transfer case buttons
are located to the left of
the instrument panel
cluster.
Use these switches to shift into and out of four-wheel
drive.
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Electronic Transfer Case
If your four-wheel-drive
vehicle has the electronic
transfer case, the
transfer case switches are
located to the left of the
instrument panel cluster.Use these switches to shift into and out of four-wheel
drive. You can choose among three driving settings:
Recommended Transfer Case Settings
Transfer Case Settings
Driving Conditions 2HI 4HI 4LO N
Normal YES
Severe YES
Extreme YES
Vehicle in Tow* YES
*See
Recreational Vehicle Towing on page 4-54orTowing Your Vehicle on page 4-53for further
information.
h(2HI):This setting is for driving in most street and
highway situations. Your front axle is not engaged
in two-wheel drive.
G(4HI):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.
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