2004 GMC SIERRA Passenger sensing

In addition to the air bag off switch, your vehicle may
have the passenger sensing system. The passenger
sensing system is designed to turn off the right
front passenger's frontal air bag when an infant or small
child in a rear-facing infant seat, a forward-facing
child restraint, or a booster seat is detected. In addition
to the passenger sensing system, you may use the
air bag off switch located on the instrument panel to turn
the air bag off. See
Air Bag Off Switch on page 1-76andPassenger Sensing System on page 1-81.Never put a rear facing child restraint in the right front
passenger's seat unless the air bag is off. Here is why:
{CAUTION:
A child in a rear-facing child restraint can be
seriously injured or killed if the right front
passenger's air bag in¯ates. This is because the
back of the rear-facing child restraint would be
very close to the in¯ating air bag. Be sure the air
bag is off before using a rear-facing child
restraint in the right front seat position. If you
secure a forward-facing child restraint in the
right front seat, always move the right front
passenger seat as far back as it will go.
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A rear seat is a safer place to secure a forward facing
child restraint. SeeWhere to Put the Restraint on
page 1-42. If you need to secure a forward-facing child
restraint in the right front seat position, move the
seat as far back as it will go before securing a
forward-facing child restraint. See
Manual Seats on
page 1-3orPower Seats on page 1-4.
{CAUTION:
If the air bag readiness light in the instrument
panel cluster 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 in¯ate
even though the switch is off. If this ever
happens, have the vehicle serviced promptly.
Until you have the vehicle serviced, do not let
anyone whom the national government has
identi®ed as a member of a passenger air bag
risk group sit in the right front passenger's
position (for example, do not secure a
rear-facing child restraint in the right front
passenger's seat). See²Air Bag Off Switch²in
the Index.If your child restraint is equipped with the LATCH
system, see
Lower Anchorages and Top Tethers for
Children (LATCH System) on page 1-48. SeeTop Strap
on page 1-43if your child restraint has one.
If your child restraint does not have the LATCH system,
you will be using the lap-shoulder belt to secure the
child restraint in this position. Be sure to follow the
instructions that came with the child restraint. Secure
the child in the child restraint when and as the
instructions say.
1. Your vehicle has a right front passenger's frontal air
bag. See
Air Bag Off Switch on page 1-76andPassenger Sensing System on page 1-81. If your
child restraint is forward-facing, move the seat as far
back as it will go before securing the restraint in
this seat. See
Manual Seats on page 1-3orPower
Seats on page 1-4. If you need to use a rear-facing
child restraint in this seat, make sure the air bag
is off once the child restraint has been installed.
When the passenger sensing system or the air bag
off switch has turned off the right front passenger's
frontal air bag, the off indicator in the passenger
air bag status indicator should light and stay lit when
you turn the ignition to RUN or START. See
Passenger Air Bag Status Indicator on page 3-40.
2. Put the child restraint on the seat.
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6. To tighten the belt, push down on the child restraint,
pull the shoulder belt to tighten the lap belt portion
and feed the shoulder belt back into the retractor.
If you are using a forward-facing child restraint, you
may ®nd 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.
7. Push and pull the child restraint in different
directions to be sure it is secure.8. If your vehicle has the passenger sensing system
and the air bag is off, the off indicator will be lit and
stay lit in the inside rearview mirror when the key
is turned to RUN or START. Never put a rear-facing
child restraint in the right front passenger seat
unless the air bag is off.
If a child restraint has been installed and the on
indicator is lit, turn the vehicle off. Remove the child
restraint from the vehicle and reinstall the child restraint.
If after reinstalling the child restraint and restarting
the vehicle, the on indicator is still lit, check to make
sure that the vehicle's seatback is not pressing the child
restraint into the seat cushion. If this happens, slightly
recline the vehicle's seatback and adjust the seat
cushion if possible. Also make sure the child restraint is
not trapped under the vehicle head restraint. If this
happens, adjust the head restraint.
If the on indicator is still lit, use the air bag off switch to
turn off the air bag or secure the child in the child
restraint in a rear seat position in the vehicle if one is
available and check with your dealer. See
Air Bag
Off Switch on page 1-76for more on this, including
important safety information.
For heavy duty pickups without the passenger sensing
system, use the air bag off switch to turn the air bag off or
install the infant restraint in a rear seat position.
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{CAUTION:
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 in¯ates. This is because the back of
the rear-facing child restraint would be very
close to the in¯ating 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 move freely again and be ready to work for an
adult or larger child passenger.If you had turned the air bag off with the switch,
remember to be sure to use the air bag off switch to
turn on the right front passenger's air bag when
you remove the child restraint from the vehicle unless
the person who will be sitting there is a member of
a passenger air bag risk group. SeeAir Bag Off Switch
on page 1-76.
{CAUTION:
If the right front passenger's air bag is turned
off for a person who isn't in a risk group
identi®ed 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 in¯ate 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. See²Air Bag Off Switch²in the Index
for more on this, including important safety
information.
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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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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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United States with Passenger Sensing SystemUnited States without Passenger Sensing System
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