1994 GMC SIERRA heater

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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I NOTICE:
Scraping the inside of your rear window could cut and damage
the defogger. Your warranty would not cover this damage. And,
don’t put decals there, you might have to scrape them
off.
For best results, clear the window of as much snow or ice as possible first.
To turn on the rear
window defogger, find
the switch marked
REAR DEFOG on
your instrument panel,
just below the heater
system. Press the right
side
of the switch,
with the defog symbol
on it,
until the light in
the switch comes on,
then release
it.
The rear window defogger will only work if the ignition switch is turned to
RUN.
You can turn the defogger off at any time by pressing the left, lighted side of
the switch. The defogger will shut itself off after several minutes, so that the
isn’t clear, turn
the defogger on again.
a olass does not get too hot. If the defogger shuts off, and the window still
Audio Systems
Your Delco@ audio system has been designed to operate easily and give
years of listening pleasure.
You will get the. most enjoyment out of it if you
acquaint yourself with
it first. Find out what your Delco@ system can do
and
how to operate all its controls, to be sure you’re getting the most out of
the advanced engineering that went into
it.
Be aware that hearing damage from loud noise is almost undetectable until
it is too late. Your hearing can adapt to higher volumes of sound. Sound that
seems normal can be loud and harmful
I:O your hearing. Take precautions by
adjusting the volume control
on your radio to a safe sound level before your
hearing adapts to it.
To help avoid hearing loss or damage:
0 Adjust the volume control to the lowest setting.
Increase volume slowly until you hear comfortably and clearly.
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I
Run your engine only as long as you must. This saves fuel. When you run
the engine, make it go a little faster than just idle. That is, push the
accelerator slightly. This uses less fuel for the heat that you get and it keeps
the battery (or batteries) charged.
You will need a well-charged battery (or
batteries) to restart the vehicle, and possibly for signaling later on with your
headlights. Let the heater run for awhile.
If you have a diesel engine, you may have to run it at a higher speed to get
enough heat. Then, shut the engine off and close
the window almost all the
way to preserve the heat. Start the engine again and repeat this only when
you feel really uncomfortable from the cold. But do it as little as possible.
Preserve the fuel
as long as you can. To help keep warm, you can get out of
the vehicle and do some fairly vigorous exercises every half hour or so until
help comes.
Power Winches
If you wish to use a power winch on your vehicle, only use it when your
vehicle
is stationary or anchored.
When operating a power winch on your vehicle, always leave the\

transmission
in "N" (Neutral). Leaving a automatic transmission
in "P" (Park) while using a power winch may damage the
transmission.
Also, leaving an automatic or manual transmission
in gear while using a power winch may damage the
transmission.
Use the regular brakes, set the parking brake, or block the wheels to keep
your vehicle
from rolling.
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If No Steam Is Coming From Your Engine
If you get the overheat warning but see or hear no steam, the 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.
0 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 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 “N” (Neutral).
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 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 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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Cooling System -Gas Engines
When you decide it's
safe to lift the hood,
here's what you'll see:
A. Coolant recovery
tank
B. Engine fan(s)
C. Radiator pressure
cap
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.
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I NOTICE:
In cold weather, water can freeze and crack the engine, radiator, \
heater core and other parts. Use the recommended coolant.
When the coolant in the coolant recovery tank is at or above the COLD
mark, start your vehicle.
If the overheat warning continues, there’s one more thing you can try. You
can add the proper coolant mix directly to the radiator!, but be sure the
cooling system is cool before
you do it.
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A CAUTION:
If your vehicle has air conditioning, the auxiliary electric fa\
n
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 surge tank is boiling, don’t do anything else
until it cools down.
E The coolant level
should be slightly
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.
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... . . , .. ..,. ~.
NOTICE:
In cold weather, water can freeze and crack the engine, radiator, \
heater
core and other parts. So use the recommended coolant.
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