1993 GMC SIERRA air conditioning

Comfort Controls & Audio Systems
Section
?
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 system
supplied with your vehicle.
For explanation of vehicle symbols in this secrlon, reTer to “Vehicle
Symbols” in Section 0.
Comfort Control System ........................................................................\
............... 3-2
Flow-Through Ventilation System
..................................................................... 3-2
Heating System (Without Air Conditioning)
..................................................... 3-4
Heater Output
........................................................................\
............................ 3-5
Electronic Heating/Air Conditioning System ..................................................... 3-5
Rear Window Defogger
........................................................................\
............. 3-8
Audio Systems
........................................................................\
............................... 3-9
FM Stereo ........................................................................\
.................................. 3-9
AM
....... . ... . . . . . , .. . . . . . . . . . . .. ... .. .. . . . . . . .. . . . . . ... . .. .. . .. ,. . . . . , . . , . . . . .. . . .. ... .. .. . . . . . . , . . . . ... . . . .... . .. . . . . . .3-9
AM Stereo
............................................. ........................................................... 3-1 0
How to Operate Your AM ETR@Radio ......................................................... 3-10
How to Operate Your AM-FM Stereo Audio System
and Cassette Deck
.II..I.I..I.I...................................I...........I...........\
.............. 3-11
How to Operate Your AM-FM Stereo Audio System
and Cassette Deck with Equalizer
.............,.,.,...................,........................... 3-14
Care of Your Cassette Tape Player
............................................................... 3-18
Fixed Mast Antenna
.................................. ...................................................... 3-1 8
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Comfort Controls & Audio Systems
Comfort Control System
Flow-Through Ventilation System
K2302
Your vehicle's flow-through 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 grilles, through the vehicle and out \
the rear air exhaust
valves. Outside air will also enter the vehicle when the heate\
r or the air
conditioning fan is running.
Ventilation Tips
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 wind\
ows.
When you enter a vehicle in cold weather, turn the blower fan to
HI for
a few moments before driving
off. This helps clear the intake ducts of
snow and moisture, and reduces the chance of fogging the insid\
e of
your windows.
Keep the air path under the front seats clear of objects. This helps air
to circulate throughout your vehicle.
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Air Vents
I
I
K2315
You will find air vents in the center and on the sides of your instrument
panel. You can move the vents to direct the flow of air, or close the vents
altogether. When you close a vent, it will increase the flow
of air coming out
of any vents that are open.
If your vehicle does not have air conditioning, there are air ven\
ts below the
instrument panel. Each vent has a handle with a vent symbol o\
n
it. Use the
handle to open and close the vent.
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Comfort Conhvls & Audio Systems
Heating System (Without Air Conditioning)
K2441
If your vehicle does not have air conditioning, this is what your heat\
ing
system will
look like.
Fan Knob
The knob on the right has four positions. To increase the air flow, turn it
toward
(t). To decrease the air flow, turn it toward (-).
Temperature Lever
The bottom lever lets you select the temperature of the air flowing into your
vehicle. Move the lever right toward
(t) for warmer air. Move the lever left
toward
(-) for cooler air.
Function Lever
The top lever can be moved to three different heating function\
s.
Defrost (Right): This setting operates the defroster. Heated air comes out
near the windshield. Use this when you get fog
or ice on the windshield.
Heater (Center): Heated air comes out near the floor. This is best for cold
weather.
Vent (Left): The air comes out at the vents on your instrument panel and
at your front side windows.
Placing the lever between positions sends air out both vents.
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Heater Output
Optional Engine Block Heater
If your engine is equipped with an optional engine block heater, you can use
it during initial start-up in cold weather (20”F,
-8”C, or lower) to help heat the
passenger compartment faster. Because an engine block heater war\
ms the
engine coolant, your vehicle’s heating system can provide som\
e heat as soon
as you start the engine.
The use
of an engine block 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 Block
Heater” in the Index.
Diesel Engine
If you idle your diesel engine for a long time when it’s cold\
outside, your
heater may blow out cool air. This is normal. When you increase the \
engine
speed, your heater should blow out warmer air.
If it doesn’t, your coolant
level may be
low. See “Engine Coolant’’ in the Index to find out how to
check your coolant level.
Electronic HeatingAir Conditioning System
Function Display
K2305
If your vehicle has air conditioning, your heating/air conditioning \
system will
look like this.
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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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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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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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