gas type GMC SIERRA DENALI 2005 Owners Manual

In any particular crash, no one can say whether an
airbag should have inated simply because of the
damage to a vehicle or because of what the repair costs
were. Ination is determined by the angle of the
impact and how quickly the vehicle slows down in frontal
or near-frontal impacts.
The airbag 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. SeeOperating
Your All-Wheel-Drive Vehicle Off Paved Roads on
page 4-13for more tips on off-road driving.
What Makes an Airbag Inate?
In an impact of sufficient severity, the airbag sensing
system detects that the vehicle is in a crash. The
sensing system triggers a release of gas from the
inator, which inates the airbag. The inator, airbag,
and related hardware are all part of the airbag modules
inside the steering wheel and in the instrument panel
in front of the right front passenger.
How Does an Airbag Restrain?
In moderate to severe frontal or near-frontal collisions,
even belted occupants can contact the steering wheel or
the instrument panel. Airbags supplement the protection
provided by safety belts. Airbags distribute the force of
the impact more evenly over the occupant’s upper body,
stopping the occupant more gradually. But airbags 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
airbags. Airbags 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.
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California Fuel
If your vehicle is certied to meet California Emission
Standards (see the underhood emission control label), it
is designed to operate on fuels that meet California
specications. If this fuel is not available in states
adopting California emissions standards, your vehicle
will operate satisfactorily on fuels meeting federal
specications, but emission control system performance
may be affected. The malfunction indicator lamp may
turn on and your vehicle may fail a smog-check test. See
Malfunction Indicator Lamp on page 3-36. If this
occurs, return to your authorized GM dealer for
diagnosis. If it is determined that the condition is caused
by the type of fuel used, repairs may not be covered
by your warranty.
Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent engine and fuel system deposits from forming,
allowing your emission control system to work properly. In
most cases, you should not have to add anything to your
fuel. However, some gasolines contain only the minimum
amount of additive required to meet U.S. Environmental
Protection Agency regulations. General Motors
recommends that you buy gasolines that are advertised
to help keep fuel injectors and intake valves clean.If your vehicle experiences problems due to dirty injectors
or valves, try a different brand of gasoline. Also, your GM
dealer has additives that will help correct and prevent
most deposit-related problems.
Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines may be available in
your area to contribute to clean air. General Motors
recommends that you use these gasolines, particularly if
they comply with the specications described earlier.
Notice:Your vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber
parts. That damage would not be covered under
your warranty.
Some gasolines that are not reformulated for low
emissions may contain an octane-enhancing
additive called methylcyclopentadienyl manganese
tricarbonyl (MMT); ask the attendant where you buy
gasoline whether the fuel contains MMT. General Motors
does not recommend the use of such gasolines. Fuels
containing MMT can reduce the life of spark plugs and
the performance of the emission control system may be
affected. The malfunction indicator lamp may turn on. If
this occurs, return to your authorized GM dealer for
service.
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Bulb Replacement
For the proper type of replacement bulbs, see
Replacement Bulbs on page 5-54.
For any bulb changing procedure not listed in this
section, contact your dealer.
Halogen Bulbs
{CAUTION:
Halogen bulbs have pressurized gas inside and
can burst if you drop or scratch the bulb. You or
others could be injured. Be sure to read and
follow the instructions on the bulb package.
Headlamps
To replace a headlamp bulb, do the following:
1. Remove the two pins on the top of the headlamp
assembly. To remove the outer pin, turn outward
and pull it straight up. To remove the inner pin, turn
it in and pull it straight up.
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