1997 GMC SIERRA air condition

When should an air bag inflate?
An air bag is designed to inflate in a moderate to severe
frontal or near-frontal crash. The air bag will inflate
only
if the impact speed is above the system’s designed
“threshold level.”
If your vehicle goes straight into a
wall that doesn’t move or deform, the threshold level
is
about 9 to 16 mph (14 to 26 km/h). The threshold level
can vary, however,
with specific 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 inflate in rollovers, side
impacts or rear impacts, because inflation would not
help
the occupant.
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
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”
in the Index for more tips on off-road driving.
What makes an air bag inflate?
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 inflator, which
inflates the air bag. The inflator, 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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Adding Equipment to Your Air
Bag-Equipped Vehicle
&.’ If I add a push bumper or a bicycle rack to the
front
of my vehicle, will it keep the air bags
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
air bags from working properly
in a crash.
e.’ Is there anything I’might add to the front of the
vehicle that could keep the air bags from
working properly?
A: Yes. If you add things that change your vehicle’s
frame, bumper system, front end sheet metal or
height, they may keep
the air bag system from
working properly.
Also, the air bag system may not
work properly if you relocate any of the air bag
sensors.
If you have any questions about this, you
should contact Customer Assistance before
you
modify your vehicle. (The phone numbers and .
addresses for Customer Assistance are in Step Two of
the Customer Satisfaction Procedure in this manual.
See “Custotner Satisfaction Procedure”
in the Index.)
e.’ What if I add a snow plow? Will it keep the air
bags 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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/I CAUTION: I
If the air bag readiness light 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 inflate
even though the switch is
off. If this ever
happens, don’t secure a rearfacing child
restraint in your vehicle until you have your
vehicle serviced.
Charging System Indicator Light
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 generator 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 the air conditioner.
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Malfunction Indicator Lamp (Service
Engine Soon Light) (Gasoline Engine)
SERVICE
ENGINE
SOON
Your vehicle is equipped
with a computer which
monitors operation of the
fuel, ignition and emission
control systems.
This system is called OBD
II (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 II 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.
This may prevent more serious
damage to your vehicle. This system is
also designed
to assist your service technician in correctly diagnosing
any malfunction.
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.
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:
0 Reducing vehicle speed.
0 Avoiding hard accelerations.
0 Avoiding steep uphill grades.
0 If you are 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,
stup the vehicle. Find a safe place to park your vehicle.
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 recently put fuel into your vehicle?
If
so, 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. A loose or
missing fuel cap
will allow fuel to evaporate into the
atmosphere.
A few driving trips with the cap properly
installed 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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Section 3 Comfort Controls and Audio Systems
In this section, you’ll find out how to operate the comfort control and audio systems offered with your vehicle. Be
sure to read about the particular systems supplied with your vehicle.
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3-4
3-4
3-5
3-6 3-6
3-7
3-7
3-8 3-8
3-9
3- 12 Comfort Controls
Air Conditioning
Heating
Ventilation System
Defogging and Defrosting
Rear Window Defogger
Audio Systems Setting the Clock
AM-FM Stereo Radio
Playing the Radio
AM-FM Stereo with Cassette Tape Player
AM-FM Stereo with Cassette Tape and
Automatic Tone Control
3- 15
3- 16
3-20
3-21
3-23 3-24
3-25
3-26
3-26 CD
Adapter Kit
AM-FM Stereo with Compact Disc Player and
Automatic Tone Control
Playing a Compact Disc in the Single Remote
Disc Player
Theft-Deterrent Feature
Understanding Radio Reception
Tips About Your Audio System Care
of Your Cassette Tape Player
Care of Your Compact Discs
Fixed Mast Antenna
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Heater and Air Conditioning Control
System
(If Equipped)
Fan Knob
The knob on the le.ft 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.
In
OFF, while driving, ram airflow will vent to the floor
outlets. The mode knob will not redirect ram airflow
to
other selected outlet positions. This is normal operation
for the
OFF position.
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.
Mode Knob
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.
e0
/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.
+’ HEATER: This setting directs air through the
heater floor outlets.
+’ DEFOG: This setting directs air to the heater
outlets and toward
the windshield.
*.
w.
DEFROST This setting directs air toward
the windshield.
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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 its 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.
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
VENTMEAT 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 (-8OC) 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.
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