1993 GMC SIERRA air condition

Comfort Controls & Audio Systems
When you first turn on your vehicle’s air conditioning, open\
the windows to
clear the vehicle of hot air.
K2313
Your system has a lighted display showing each system when it is operating.
During normal operation, all the lights won’t come on at th\
e same time. Only
the ones displaying the current settings will light.
System Controls
NC Button: Press the button marked NC to turn your air conditioner on and
off. The NC symbol will light on your display and air will come out of y\
our
dashboard vents. The fan will automatically be set on
LOW.
When you press the NC button to turn the air conditioner off, the system will
operate in the vent mode. When you turn the air conditioner back on, the\

system will operate in the mode that you last selected unless the
OFF button
was pressed.
OFF Button: Press this button to turn the air conditioninglheating \
system off.
Pressing OFF will erase the present mode of operation from the system’s
memory. Outside air will still come out of the heater outlet whenever the
vehicle is moving forward.
If the OFF button was pressed, you must press NC, MAX (RECIR on some
models), or one of the
BLEND buttons for the system to come back on.
Air Controls (BLEND)
The two buttons to the right of the system display control the air flow. You
can blend the air flow to suit your needs. The amount of blending is shown
on the display by an arrow moving between the figure’s feet\
(floor air flow)
and head (vent air flow).
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Right Button
Defrost (Top): Press here to operate the defroster. Heated air comes out
near the windshield. You can use it to help clear fog or ice on your
windshield.
Heater (Bottom): Press here, and heated air comes out near the floor. This
setting is best for passenger comfort in cold weather.
The air flow can be blended between the two positions. To blend between
positions, press the side of the button showing the area where you would like
more air flow. The system will automatically begin to blend toward the position
chosen. To stop the system between positions, just press the
SAME side of
the button again.
Left Button
Vent (Top): Press the top of this button and all of the airflow will come
through the instrument panel vents.
Heater (Bottom): Press the bottom of this button and all of the airflow will
come through the floor outlet.
The air flow can be blended between the two positions.
To blend between
positions, press the side
of the switch showing the area where you would like
more air flow. The system will automatically begin to blend toward the position
chosen. To stop the system between positions, just press the
SAME side of
the button again.
Temperature Selector Bar
The bar under your system display lets you select the temperat\
ure of the air
coming into your vehicle. Press
COLD for cooler air and press HOT for
warmer air. Release the bar when the system reaches the temperature you
want. The temperature is shown on the display by an arrow moving between
C and H.
Fan Control Button
This button is in the upper right corner of your system control panel. The fan
has four settings-low, medium
low, medium high and high. Press the top of
the button
(t) to increase the air flow. Press the bottom of the button (-) to
decrease the air flow. The setting you select is shown on your display as
LOW, MED LOW, MED HI or HI.
Air Recirculation Button
If you press the MAX button (RECIR on some models), the air in your
vehicle will be recirculated. With the air conditioner on,
MAX will give you
maximum cooling. It can also be used in all modes to help keep dust out of
your vehicle. When
MAX is selected, REC will light on your display.
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Problems on the Road
If your engine catches fire because you keep driving with no cool\
ant, your
vehicle can be bac"lI damaged.
T- ! costly rep; 1 would not be Iverec
by your warranty.
If No Steam Is Coming From Your Engine:
If you get the overheat warning but see or hear no steam, th\
e problem may
not be too serious. Sometimes the engine can get a little too\
hot when you:
Climb a long hill on a hot day.
Stop after high speed driving.
Idle for long periods in traffic.
Tow a trailer.
If you get the overheat warning with no sign of steam, try t\
his 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
3. If you're in a traffic jam, shift to N (Neutral).
window as necessary.
If you no longer have the overheat warning, you can drive. Just
to be safe,
drive slower for about ten minutes.
If the warning doesn't come back on, you
can drive normally.
If the warning continues, pull over, stop, and park your vehic\
le 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 OFF THE ENGINE AND GET
EVERYONE
OUT OF THE VEHICLE until it cools down.
You may decide not to
lift the hood but to get service help right away.
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Engine Fan Noise
This vehicle has a clutched engine cooling fan. When the clutch is engaged,
the fan spins faster to provide more air to
cool the engine. In most every day
driving conditions the clutch is not engaged. This improves fue\
l economy and
reduces fan noise. Under heavy vehicle loading, trailer towing andlor high
outside temperatures, the fan speed increases when the clutch e\
ngages.
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 disengages.
If a Tire Goes Fiat
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, 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 your tire goes flat, the next part shows how to use your jacking equipment
to change a flat tire safely.
Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage by driv\
ing slowly to a
level place. Turn on your hazard warning flashers.
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Service & Appearance Cam
i r:
PO21 7
If your vehicle has air conditioning, the auxiliary fan under the \
hood
can start up and injure you even when the engine is not runn\
ing.
Keep your hands, clothing and tools away from any underhood
electric fan,
if you have one.
Things that burn can get on hot engine parts and start
a fire. These
b include liquids like gasoline or diesel fuel, oil, coolant, bra\
ke fluid,
windshield washer and other fluids, and plastic or rubber. You or
others could be burned. Be careful not
to drop or spill things that will
burn onto a hot engine.
Before closing the hood, be sure all the filler caps are
on properly. Then just
pull the hood down and close it firmly.
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1 CAUTION
4 Adding only plain water to your cooling system can be dangerous.
Plain water, or some other liquid like alcohol, can boil before th(
)per coolant mix will. Your vehicle’s coolant warning system is set
for the proper coolant mix. With plain water or the wrong mix\
, your
engine could get too hot but you wouldn’t get the overheat warning.
Your engine could catch fire and you or others could be burned. Use
a
50/50 mix of clean water and a proper antifreeze.
NOTICE
If you use an improper coolant mix, your engine could overheat an\
d 1:
badly damaged. The repair cost wouldn’t be covered by your warranty. 1
much water in the mix can freeze and xk +?e t line radiator, heater
core and other parts.
Some conditions, such as air trapped in the cooling system, can affect the
coolant level in the radiator. Check the coolant level when the engine is cold
and follow the steps under “Adding Coolant” for the prope\
r way to add
coolant.
If you have the low coolant warning system, refer to the General Motors
Service Manual or see your dealer for the proper coolant
fill procedure. (To
purchase a Service Manual, see “Service Publications’’ in the Index.) Using
the wrong
fill procedure can cause a low coolant warning indication.
If you have to add coolant more than four times a year, have your dealer
check your cooling system.
If you use the proper coolant, you don’t have to add extra inhibitors or
additives which claim to improve
the system. These can be harmful.
-
NOTICE .I
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Service & Appearance Care
Windshield Wiper Blade Inserts
I -
r
PO232
To replace the windshield wiper blade insert, lift the wiper arm and rotate the
blade until it is facing away from the windshield. Unlatch the\
end of the insert
from the holding clips. Remove the insert and slide a new one\
in place.
Make sure the blade is secured in the clips.
Air Conditioning
Every now and then have your dealership check your air conditi\
oning system
to be sure it has not lost any cooling ability.
If you think the system is not
working properly, have your dealership check it out as soon as\
possible.
The air conditioning will not work when the temperature is bel\
ow 40°F
(4°C).
Fluid Leak Check
After the vehicle has been parked for a while, inspect the su\
rface under the
vehicle
for water, oil, fuel or other fluids. Water dripping from the air
conditioning system after it has been used is normal, If you notice fuel leaks
or fumes, the causes should be found and corrected at once.
Lubrication
Accelerator Control System
Your maintenance schedule will tell you how often the accelerator linkage
pivot points must be lubricated. See “Recommended Fluids and \
Lubricants” in
the Index for the proper lubricant to use.
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r CAUTION I
If you operate your vehicle with a tire that is badly underinflated, the
tire can overheat. An overheated tire can lose air suddenly or catcl.
fire. You or others could be injured. Be sure all tires (including the
spare,
if any) are properly inflated.
Buying New Tires
To find out what kind and size of tires you need, look at the Certificationflire
label. The tires installed on your vehicle when it was new had a Tire
Performance Criteria Specification (TPC Spec) number on each tire’s sidewall.
When you get new tires, get ones with that same TPC Spec num\
ber. That
way, your vehicle will continue to have tires that are designed to give proper
endurance, handling, speed rating, traction, ride and other thin\
gs during
normal service on your vehicle. If your tires have an all-season tread design,
the TPC number will be followed by a
“MS” (for mud and snow).
If you ever replace your tires with those not having a TPC Spec number,
make sure they are the same size, load range, speed rating and construction
type (bias, bias-belted
or radial) as your original tires.
1 CAUTION
* Mixing tires could cause you to lose control while driving. If you mix
vehicle may not handle properly, and you could have a crash. Be
- ) tires of different sizes or types (radial and bias-belted tires), the
I sure to use the same size and type tires on all wheels. I
Uniform Tire Qua/ity Grading
The following information relates to the system developed by the United
States National Highway Traffic Safety Administration which grade\
s tires by
treadwear, traction and temperature performance. (This applies o\
nly to
vehicles sold in the United States.)
Treadwear
The treadwear grade is a comparative rating based on the wear rate of the
tire when tested under controlled conditions on a specified governmen\
t test
course. For example, a tire graded
150 would wear one and a half (1 1/2)
times as well on the government course as a tire graded 100. The relative
performance
of tires depends upon the actual conditions of their use,
however, and may depart significantly from the norm due to var\
iations in
driving habits, service practices and differences in road characteristics and
climate.
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