1994 GMC SIERRA heating

Table of Contents
Introduction - How to Use this Manual
This section tells you how to use your manual and includes safety
and vehicle damage warnings and symbols.
Section 1 - Seats and Safety Restraints
This section tells you how to use your seats and safety restraints
properly.
Section 2 - Features & Controls
This section explains how to start and operate your Vehicle.
Section 3 - Comfort Controls & Audio Systems
This section tells you how to adjust the ventilation and comfort
controls and how to operate your audio system.
Section 4 - Your Driving and the Road
Here you’ll find helpful information and tips about the road\
and
how to drive under different conditions.
Section 5 - Problems on the Road
This section tells you what to do if you have a problem while
driving, such as
a flat tire or engine overheating.
Section 6 - Service & Appearance Care
Here the manual tells you how to keep your Vehicle running
properly and looking good.
Section 7- Schedule Maintenance Services
This section tells you when to perform vehicle maintenance and
what fluids and lubricants to use.
Section 8 - Customer Assistance Information
This section tells you how to contact your GM division for
assistance and
how to get service publications. It also gives you
information on “Reporting Safety Defects” on page
8-4.
Index
Here’s an alphabetical listing of almost every subject in th\
is
manual. You can use
it to quickly find something you want to read.
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Cigarette Lighter/Ashtrays
The front ashtray is
located at the bottom
of the instrument
panel. Pull on the
bottom of the ashtray
door to open it.
To use the cigarette lighter, push it in all the way, and let go. When it’s
ready, it will pop back by itself.
I NOTICE:
Don’t hold a cigarette lighter in with your hand while it is
heating. If you do, it won’t be able to back away from the
heating element when it’s ready. That can make it overload, \
damaging the lighter and the heating element.
To remove the front ashtray, pull on the front of the ashtray insert. Then
slide the insert out
of the ashtray door.
To use
a rear ashtray,
if you have them, pull at the top
of the
ashtray door to flip the
door open.
To remove a rear ashtray, if you have them, press down on the i\
nside tabs
and open the door fully.
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actually took a little more or less than half the tank’s capacity to fill the
tank.
The gage moves a little when you turn a corner or speed up.
The gage doesn’t go back to empty when you turn off the ignition.
None of these indicate a problem with
the fuel gage.
For information on how to
fill your fuel tank, see “Fuel - Filling Your
Tank”
in the Index.
For your fuel tank capacity, see
“Fuel --Tank Capacity” in the Index.
Engine Coolant Temperature Gage
This gage shows the engine coolant temperature. If the gage pointer moves
into the red area, about
260” F ( 145” C) or more, your engine is too hot! It
means that your engine coolant has overheated. If you have been operating
your vehicle under normal operating conditions, you should pull off the
road, stop
your vehicle, and turn off the engine as soon as possible.
Hot Cooianf Can Burn You Badly!
In “Problems on the Road,” this ~nanual shows what to do. See “Engine
Overheating”
in the Index.
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Comfort Controls and 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 section. refer to “Vehicle
Symbols” in the Introduction
.
Comfort Control System
Flow-Through Ventilation System
........................... 3-2
Heating System (Without Air Conditioning)
................... 3-5
Electronic Heating/Air Conditioning System ................... 3-6
Rear Window Defogger
................................... 3-8
Audiosystems
............................................. 3-9
FMStereo ............................................. 3-10
AM
.................................................. 3-10
AMStereo
............................................. 3-10
How to Operate Your AM ETR@ Radio
...................... 3-11
How to Operate
Your AM-FM Stereo Audio System and Cassette
Deck
............................................... 3-12
How to Operate Your AM-FM Stereo Audio System and Cassette
Deck with Equalizer
.................................. 3-16
Care of Your Cassette Tape Player
.......................... 3-20
Fixed Mast Antenna
........................ ..r . . 3-21
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Heater Output
Engine Coolant Heater (Engine Block Heater)
If your vehicle has a diesel engine, it is equipped with an engine coolant
heater. An engine coolant heater
is optional on gas engine vehicles. You can
use an engine coolant heater during initial start-up
in cold weather (20” F,
-8” C, or lower) to help heat the passenger compartment faster. Because an
engine coolant heater warms the engine coolant, your vehicle’s heating
system can provide some heat
as soon as you start the engine.
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.
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.
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Weating System (Without Air Conditioning)
If your vehicle does not have air conditioning, this is what your heating
system
will look like.
Function Le wer
The upper lever on the control panel can be moved to three different heating
functions.
0
0
0
Vent (Left): Air comes out at the vents on your instrument panel and at
your front side windows.
Heater (Center): Air comes out near the floor. This setting, along
with a heat setting, is best for cold weather.
Defrost (Right): This setting operates the defroster. Air comes out
near the bottom of the windshield and at your front side windows. Use
this setting, along
with a heat setting, when you get fog or ice on the
windshield.
Placing the lever between positions sends air out both vents.
Temperature Le wer
The lower lever on the control panel lets you select the temperature of the
air flowing into the passenger area
of your vehicle. Move the lever right
toward
“+” for warmer air. Move the lever left toward “-” for cooler air.
Fan Control Knob
The knob on the right side of the heating system control panel controls the
fan speed. The knob has four speed positions. To increase the air flow, turn
the knob toward
“+”. To decrease the air flow, turn it toward “-”.
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Electronic Heating/Air Conditioning System
If your vehicle has air conditioning, your heating/air conditioning system
will look like this.
When
you first turn on your vehicle’s air conditioning, open the windows to
clear the vehicle of hot air. Using the
MAX button can also help. See
“MAX Button” in this section for more information.
Function Display
Your system has a lighted display showing each system when it is operating.
During normal operation, all the lights won’t come
on at the same time.
Only the ones displaying the current settings will
light.
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A/C Button
Press the button marked A/C to turn your air conditioner on and off. The
A/C symbol will light on your display and air will come out of your
instrument panel vents. The fan
will automatically be set on LOW.
When you press the A/C 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 selectcd unless the OFF
button was pressed.
MAX Button
If you press the MAX button, 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 vchicle. When MAX
is selected, REC will light on your display.
If your air conditioner develops high system pressure, it will automatically
go into the
MAX mode and REC will light on your display. The A/C
system will remain in the MAX mode, even if you press the MAX button,
until system pressure returns
to a normal level.
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
“+” 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.
OFF Button
Press this button to turn the air conditioning/heating 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 A/C, MAX, or one of the
BLEND buttons for the system to come back on.
Rear Window Defogger
You can tell if your vehicle has this option by looking at the rear window. If
you see lines running across the glass, you have it. These are the conductive
wire-like elements which heat your window.
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