1996 GMC SIERRA air condition

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
the vehicle’s deceleration. Vehicle damage is only one
indication
of this.
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.
What makes an air bag inflate?
In a frontal or near-frontal impact of sufficient severity,
the air bag sensing system detects that
the vehicle is
suddenly stopping as a result of a crash. The sensing
system triggers
a chemical reaction of the sodium azide
sealed
in the inflator. The reaction produces nitrogen
gas, which inflates the air bag. The inflator, air bag and
related hardware are all part of the air bag module
packed inside the steering wheel.
How does an air bag restrain?
In moderate to severe frontal or near-frontal collisions,
even belted occupants can contact the steering
wheel.
The air bag supplements 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 side impacts, primarily
because an occupant’s motion
is not toward the air bag.
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 the air bag inflates, it quickly deflates. This occurs
so quickly that some people may not even realize the air
bag inflated. Some components
of the air bag module in
the steering wheel hub will be hot for a short time. The
part of the bag that comes into contact with you
may be
warm, but
it will never be too hot to touch. There will be
some smoke and dust coming from vents
in the deflated
air bag.
Air bag inflation will not prevent the driver
from seeing or from being able
to steer the vehicle, nor
will it stop people from leaving the vehicle.
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I
Servicing Your Air Bag-Equipped Vehicle
1 The air bag affects how your vehicle should be serviced.
There
are parts of the air bag system in several places
around your vehicle. You don’t want
the system to
inflate while someone is working on your vehicle. Your
GM dealer and the service manual have information
about servicing your vehicle and the air bag system.
To
purchase a service manual, see “Service and Owner
Publications” in the Index.
For up to two minutes after the ignition key
is
turned off and the battery is disconnected, an air
bag can still inflate during improper service. You
can be injured if you are close to an air bag when
it inflates. Avoid wires wrapped with yellow tape,
or yellow connectors. They are probably part of
the
air bag system. Be sure to follow proper
service procedures, and make sure the person
performing work for you is qualified to do
so.
~~ ~~ ~~
The air bag system does not need regular maintenance.
Adding Equipment to Your Air
Bag-Equipped Vehicle
Q: If I add a push bumper or a bicycle rack to the
front
of my vehicle, will it keep the air bag from
working properly?
A: As long as the push bumper or bicycle rack is
attached to your vehicle
so that the vehicle’s basic
structure isn’t changed, it’s not likely to keep the
.I air bags from wor@ng properly in a crash.
What if
I add a snow plow? Will it keep the air
bag from working properly?
A: We’ve designed our air bag systems to work
properly under a wide range of conditions,
including snow plowing with vehicles equipped
with the optional Snow Plow Prep Package
(RPO VYU). But don’t change or defeat the
snow plow’s “tripping mechanism.” If you do,
it
can damage your snow plow and your vehicle,
and it may cause an air bag inflation.
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Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel, which shows AIR BAG. The system checks the
air bag’s electrical system for malfunctions. The light
tells
you if there is an electrical problem. The system
check includes the air bag sensors, the air bag module,
the wiring and the diagnostic module. For more
information
on the air bag system, see “Air Bag” in
the Index.
AIR
BAG
You will see this light flash
for a few seconds when you
turn your ignition
to RUN
or START. Then the light
should go out. This means
the system is ready.
Charging System Indicator Light
If the air bag readiness light doesn’t come on when you
start your vehicle, or stays on, or comes on when you
are driving, your air bag system may not work properly.
Have your vehicle serviced right away. This
light should come
on
briefly when you turn on the
ignition, before starting the
engine, as
a check to show
you it is working.
After the engine starts,
the light should go out. If it stays
on or comes on while
you are driving, you may have a
problem with your charging system. It could indicate a
problem with the alternator drive belt,
or some other
charging system problem. Have
it checked right away.
Driving while this light is on could drain your battery.
If
you must drive a short distance with this light on, it
helps to turn off all your accessories, such
as the radio
and air conditioner.
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Malfunction Indicator Lamp (Service
- ;ine Soon Light) (Gasoline Engine)
Your vehicle is equipped
with a computer which
monitors operation
of the
fuel, ignition and emission SERVICE
ENGINE
SOON
control systems.
This system
is called OBD I1 (On-Board
Diagnostics-Second Generation) and is intended to
assure that emissions are at acceptable levels for the
life of the vehicle, helping to produce a cleaner
environment. (In Canada,
OBD TI is replaced by
Enhanced Diagnostics.) The
SERVICE ENGINE SOON
light comes on to indicate that there is a problem and
service
is required. Malfunctions often will be indicated
by the system before any problem
is apparent, which
may prevent more serious damage to your vehicle. This
system is
also designed to assist your service technician
in correctly diagnosing any malfunction.
I NOTICE:
If you keep driving your vehicle with this light
on, after a while, your emission controls may not
work as well, your fuel economy may not be as
good and your engine may not run as smoothly.
This could lead
to costly repairs that may not be
covered by your warranty.
This light should come on, as a check to show you it is
working, when the ignition is
on and the engine is not
running.
If the light doesn’t come on, have it repaired.
This light will also come
on during a malfunction in one
of two ways:
0 Light Flashing -- A misfire condition has been
detected.
A misfire increases vehicle emissions and
may damage
the emission control system on your
vehicle. Dealer or qualified service center diagnosis
and service
is required.
0 Light On Steady -- An emission control system
malfunction has been detected on your vehicle.
Dealer or qualified service center diagnosis and
service may be required.
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If the Light Is Flashing If the Light Is On Steady
The following may prevent more serious damage to
your vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid steep uphill grades.
0 If towing a trailer, reduce the amount of cargo being
hauled
as soon as it is possible.
If the light stops flashing and remains
on steady, see “If
the Light
Is On Steady” following.
If the light continues to flash, when it is safe to do so,
stop the vehicle. Put your vehicle in PARK (P). Turn the
key off, wait at least
10 seconds and restart the engine.
If the light remains
on steady, see “If the Light Is On
Steady” following.
If the light is still flashing follow the
previous steps, and drive the vehicle
to your dealer or
qualified service center for service.
You may be able to correct the emission system
malfunction by considering the following:
Did you just put fuel
into your vehicle?
If so7 reinstall the fuel cap, making sure to fully install
the cap. The diagnostic system can determine if the fuel
cap has been left off or improperly installed. This will
allow fuel to evaporate into
the atmosphere. A few
driving trips should turn the light off.
Did
you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will
usually be corrected when the electrical system
dries out.
A few driving trips should turn the light off.
Are you low on fuel?
As your engine starts to run out of fuel, your engine may
not run as efficiently as designed since small amounts of
air are sucked into the fuel line causing a misfire. The
system can detect this. Adding fuel should correct this
condition. Make
sure to install the fuel cap properly. it
will take a few driving trips to turn the light off.
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Mode Knob Optional Climate Control System
The right knob on the control panel allows you to
choose
the direction of air delivery. The control knob
can be placed in any position between two mode settings
to blend the
flow of air.
+e
/J VENT: This setting directs air through the
instrument panel outlets.
+’ VENT/HEAT Use this setting to divide airflow
between
the floor outlets and instrument panel outlets.
+iJ HEATB; This setting directs air through the
floor outlets.
6fl DEFOG: This setting directs air to the heater
outlets and toward the windshield.
9 DEFROST: This setting directs air toward
the windshield.
+*
e
(ii3, Fan Knob
The knob on the left side of the heating system control
panel controls the fan speed. The knob has four speed
positions. To increase airflow, move the knob toward
HI. To decrease airflow, move it toward LO. To turn the
fan off, move the knob to
OFF. If you have the air
conditioner on. moving
the fan knob to OFF also turns
off the A/C compressor.
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Temperature Knob
The middle knob on the control panel lets you select the
relative temperature
of the air flowing into the passenger
area of your vehicle. This knob will allow you to adjust
the relative air temperature independently
of the
function knob setting. Move the knob clockwise
toward
the red area for warmer air. Move the knob
counterclockwise toward the blue area for cooler air.
The right knob on the control panel allows you to
choose the direction of air delivery. The control knob
can be placed
in any position between two mode settings
to blend the flow of air.
/J VENT: This setting directs air through the
instrument panel outlets.
+H VENT/HEAT Use this setting to divide airflow
between the floor outlets and instrument panel outlets.
+’ HEATER: This setting directs air through the
heater floor outlets.
+e
+.
0
Qe
+’ DEFOG: This setting directs air to the heater
outlets and toward
the windshield.
DEFROST This setting directs air toward the
windshield.
Air Conditioning
On hot days, open the windows long enough to let hot
air inside escape. This reduces the time it takes for your
vehicle
to cool down. Then keep your windows closed
for
the air conditioner to work it’s best.
The recirculation button, between the fan and
temperature knobs, allows the air inside your vehicle to
be recirculated. This setting helps
to maximize your air
conditioner’s performance and your vehicle’s fuel
economy. This setting also
cools the air the fastest and
can be used
to keep unwanted odors and/or dust from
entering the vehicle. When using the air conditioner,
turn off recirculation after the vehicle reaches a
comfortable interior temperature. When the right knob
on the control panel is between HEATER and
DEFROST, the recirculation feature will
not function.
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The A/C button, between the temperature and mode
knobs, allows
the air coming into your vehicle to be
cooled. This setting
is useful for normal cooling on hot
days. When
you use A/C with the recirculation button
pushed
in, turn off recirculation as soon as the vehicle
reaches a comfortable interior temperature.
With the
A/C on, move the temperature knob to MAX
for maximum cooling.
This setting also puts the system
in the recirculation mode and helps
to maximize your air
conditioner’s performance and your vehicle’s fuel
economy. This setting also cools the air the fastest. After
the vehicle’s interior reaches a comfortable temperature,
move the temperature knob clockwise to place the air
conditioning system
in the normal mode.
Heating
The heater works best if you keep your windows closed
while using
it. On cold days, use the HEATER or
VENT/HEAT setting with the temperature knob in the
red area.
If you use the engine coolant heater before starting your
engine (in cold weather (20°F (-8°C) or lower), your
heating system
will produce warmer air faster, to heat
the passenger compartment
in cold weather. The
use
of an engine coolant heater also reduces the
time
it takes for the engine to reach normal operating
temperature, and shortens the time
it takes the heater to
reach full output. For more information, see “Engine
Coolant Heater”
in the Index.
Ventilation System
For mild outside temperature when little heating or
cooling
is needed, use VENT to direct outside air
through
your vehicle. Air will flow through the
instrument panel outlets.
Your vehicle’s ventilation systeril supplies outside air
to the inside of your vehicle when it is moving. With
the side windows closed, air will flow into the front
air inlet grilles, through the vehicle, and out the air
exhaust valves.
Outside air will
also enter the vehicle when the heater or
the air conditioning fan is running, unless you have
the
recirculation button pushed in. For more information on
the recirculation button, see “Air Conditioning” earlier
in this section.
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