1997 GMC SIERRA air condition

Ventilation System
For mild outside temperatures 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 system 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 grrlles,
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.
Your vehicle has air outlets in the center and on the sides
of your instrument panel. You can move the outlets from
side to side or up and down to direct the flow of air, or
close the outlets altogether. When you close
an outlet, it
will increase the flow
of air coming out of any outlets
that are open. These outlets do not completely shut
off
airflow when in the closed position.
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Ventilation Tips
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Keep the hood and front air inlet free of ice, snow or
any other obstruction
(such as leaves). The heater
and defroster will work far better, reducing the
chance of fogging the inside of your windows.
When you enter
a vehicle in cold weather, turn the
blower
fan to HI for a few moments before driving.
This helps clear the intake ducts of snow and
moisture, and reduces the
chance of fogging the
inside of your windows.
Keep
the air path under the front seats clear of
objects. This helps air to circulate throughout
your vehicle.
The use of hood air deflectors may adversely
affect the performance of the heating and air
conditioning system.
Defogging and Defrosting
On cool, humid days, use DEFOG to keep the
windshield and side windows clear. Use
DEFROST to
remove fog
or ice from the windshield in extremely
humid or cold conditions. Use
DEFROST with the
temperature
knob toward the red area and the fan control
toward
HI.
Rear Window Defogger (If Equipped)
If you see lines running across the rear window, you
have a rear window defogger. The lines warm the glass.
To turn
on the rear window
defogger, press this button
next to
the fan control knob.
The rear window defogger
will only work if the
ignition switch is turned
to RUN. For best results,
clear
the window of as
much snow or ice as
possible first.
The defogger will shut itself off after several minutes.
If you need additional warming time, press the button
again. You can turn the defogger off at any time by
pressing the button.
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2. Get the vehicles close enough so the jumper cables
can reach, but be
sure the vehicles aren’t touching
each other. If they are, it could cause a ground connection you don’t want. You wouldn’t be able to
start your vehicle, and the bad grounding could
damage the electrical systems.
To avoid the possibility of the vehicles rolling, set the
parking brake
fmly on both vehicles involved in the
jump stat procedure. Put an automatic transmission in
PARK (P) or a manual transmission in NEUTRAL (N).
If you have a four-wheel-drive vehicle, be sure the
transfer case is not
in NEUTRAL (N).
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or accessory power outlets. Turn
off all lamps
that aren’t needed as well
as radios. This will avoid
sparks and help save both batteries.
In addition, it
could save your radio!
I NOTICE:
If you leave your radio on, it could be badly
damaged. The repairs wouldn’t be covered by
your warranty.
4. Open the hoods and locate the batteries. Find the
positive
(+) and negative (-) terminals on each battery.
If your vehicle has air conditioning, the auxiliary
electric fan under the hood can start
up even
when the engine is not running and can injure
you. Keep hands, clothing and tools away
from
any underhood electric fan.
5-4
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If you get the overheat warning with no sign of steam,
try this for a minute or
so:
1. If you have an air conditioner, turn it off.
2. Turn on your heater to full hot at the highest fan
speed and open the window
as necessary.
3. If you’re in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving
-- AUTOMATIC OVERDRIVE (@)
for automatic transmissions.
If you no longer have
the overheat warning, you can
drive. Just
to be safe, drive slower for about 10 minutes.
If the warning doesn’t come back
on, you can
drive normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there’s still no sign of steam, push the accelerator until
the engine speed is about twice as fast as normal idle
speed. Bring the engine speed back to normal idle speed
after two or three minutes. Now see if the warning stops.
But then, if
you still have the warning, turn oflthe
engine and get everyone out
of the vehicle until it
cools down.
Cooling System -- Gasoline Engines
When you decide it’s safe to lift the hood, here’s what
you’ll see:
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Engine Fan(s)
You may decide
not to lift the hood but to get service
help right away.
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I A CAUTION:
If your vehicle has air conditioning, the auxiliary
electric fan under the hood can start
up even
when the engine is not running and can injure
you. Keep hands, clothing and tools away from
any underhood electric fan.
If the coolant inside the coolant recovery tank is boiling,
don’t do anything else until it
cools down. The
coolant level should be at or above
the COLD mark.
If it isn’t, you may have a leak in the radiator hoses,
heater hoses, radiator, water pump or somewhere else
in
the cooling system.
I
Heater and radiator hoses, and other engine
parts, can be very hot. Don’t touch them.
If you
do, you can be burned.
Don’t run the engine if there is
a leak. If you run
the engine, it could lose all coolant. That could
cause an engine fire, and you could be burned.
Get any leak fixed before you drive the vehicle.
I NOTICE:
Engine damage from running your engine
without coolant isn’t covered
by your warranty.
5-14
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Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spi.ns faster to provide
more air
to cool the engine. In most everyday driving
conditions, the fan is spinning slower and the clutch is
not fully engaged. This improves
fuel economy and
reduces fan noise. Under heavy vehicle loading, trailer towing and/or high outside temperatures, the fan speed
increases as the clutch more fully engages.
So you may
hear an increase in fan noise. This
is normal and should
not be mistaken as the transmission slipping or making
extra shifts. It is merely the cooling system functioning
properly. The fan will slow down when additional
cooling is not required and the clutch disengages.
You may also hear this
fan noise when you start the engine.
It will
go away as the fan clutch partially disengages.
If a Tire Goes Flat
It’s unusual for a tire to “blow out” while you’re driving,
especially
if you maintain your tires properly. If air goes
out
of a tire, it’s much more likely to leak out slowly.
But if you should ever have
a “blowout,” here are a
few tips about what to expect and what to do:
If a front tire fails, the flat tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you’d use in
a skid. In any rear blowout, remove your foot from
the accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to go. It may be
very bumpy and noisy, but
you can still steer. Gently
brake
to a stop -- well off the road if possible.
If a tire goes flat, the next part shows how to
use your
jacking equipment
to change a flat tire safely.
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Section 6 Service and Appearance Care
Here you will find information about the care of your vehicle. This section begins with service and fuel information,
and then it shows how
to check important fluid and lubricant levels. There is also technical information about your
vehicle, and a part devoted to its appearance care.
6-2
6-
3
6-4
6-5
6-8
6- 14
6- 15
6- 19
6-2 1
6-25
6-26
6-26 6-27
6-29
6-32
6-32 Service
Fuel (Gasoline Engine)
Fuels
in Foreign Countries - - Gasoline
Engines
Filling Your Tank
Checking Things Under the Hood
Noise Control System
Engine Oil (Gasoline Engine)
Air Cleaner Filter (Gasoline Engines)
Automatic Transmission Fluid
Manual Transmission Fluid
Hydraulic Clutch
Rear Axle
Four-wheel Drive
Engine Coolant Radiator Pressure Cap (Gasoline Engine)
Thermostat 6-33
6-33 6-35
6-39
6-39
6-49 6-50
6-59
6-60
6-64
6-68
6-69
6-70 6-75
6-76
6-78 Power Steering Fluid
Windshield Washer Fluid
Brakes
Battery
Bulb Replacement
Windshield Wiper Blade
R
Tires
Appearance Care .eplacement
Cleaning the Inside
of Your Vehicle
Cleaning
the Outside of Your Vehicle
Appearance Care Materials
Chart
Vehicle Identification Number (VIN)
Electrical System Replacement Bulbs
Capacities and Specifications
Air Conditioning Specifications
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Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airflow around it. This may cause wind noise
and affect windshield washer performance. Check with
your GM dealer before adding equipment to
the outside
of your vehicle.
Fuel (Gasoline Engine)
If your vehicle has a diesel engine, see “Diesel Fuel
Requirements and Fuel System”
in the Diesel Engine
Supplement. For vehicles with gasoline engines, please
read this.
Use regular unleaded gasoline rated at
87 octane or
higher. At a minimum, it should meet specifications
ASTM D4814 in the United States and CGSB
3.5-M93
in Canada. Improved gasoline specifications have been
developed by
the American Automobile Manufacturers
Association (AAMA) for better vehicle performance
and engine protection. Gasolines meeting
the AAMA
specification could provide improved driveability and
emission control system protection compared to
other gasolines. Be sure
the posted octane is at least 87. If
the octane is
less than
87, you may get a heavy knocking noise when
you drive. If it’s bad enough, it can damage your engine.
If you’re using fuel rated at
87 octane or higher and you
still hear heavy knocking, your engine needs service.
But don’t worry if you hear a little pinging noise when
you’re accelerating or driving up a
hill. That’s normal,
and
you don’t have to buy a higher octane fuel to get rid
of pinging. It’s the heavy, constant knock that means
you have a problem.
If your vehicle is certified to meet California Emission
Standards (indicated
on the underhood tune-up label),
it is designed to operate
on fuels that meet California
specifications. If such fuels are
not available in states
adopting California emissions standards, your vehicle
will operate satisfactorily
on fuels meeting federal
specifications, but emission control system performance
may be affected. The malfunction indicator lamp
on
your instrument panel may turn on andor your vehicle
may fail a smog-check test. If this occurs, return
to your
authorized GM dealer for diagnosis
to determine the
cause of failure. In the event it is determined that the
cause of
the condition is the type of fuels used, repairs
may not be covered by your warranty.
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