1995 GMC SIERRA heater

To turn on the rear
window defogger,
press the rear defog
button
next to the fan
control knob.
‘he rear window defogger
will only work if the ignition switch is turned to
:UN.
‘ou can turn the defogger off at any time by pressing the button again. The
efogger
will shut itself off after several minutes, so that the glass does not
et too hot.
If the defogger shuts off, and the window still isn’t clear, turn on
le defogger again.
Ventilation System
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 grilles,
through the vehicle, and out the rear air
exhaust valve.
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 see “Recirculation Button’‘ in this section.
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 windows.
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c
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.
NOTICE:
Using a power winch with the transmission in gear may damage
the transmission. When operating a power winch, always leave
the transmission in NEUTRAL
(N).
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:
0 Climb a long hill on a hot day.
0 Stop after high speed driving.
0 Idle for long periods in traffic.
Tow a trailer. See “Driving on Grades’’ in the Index.
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 (@) or
DRIVE
(3) for automatic transmissions.
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 ofSthe 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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The coolant level
should be a1 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.
A CAUTION:
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.
NOTICE:
Engine damage from running your engine without coolant isn’t
covered
by your warranty.
If there seem to be no leak. start the engine again. See if the fan speed
increases when idle speed is doubled
by pushing the accelerator pedal down.
If it doesn’t, your vehicle needs service. Turn off the engine.
How to Add Coolant to the Coolant Recovery Tank
If you haven’t found a problem yet, but the coolant level isn’t at or above
the COLD mark, add
a SO/SO mixture of c.lea12 water (preferably distilled)
and
a proper antifreeze at the coolant recovery tank. (See “Engine Coolant”
in the Index for more information about the proper coolant mix.)
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NOTICE:
In cold weather, water can freeze and crack the engine, radiat\
or,
heater core and other parts. Use the recommended coolant.
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Cooling System - Diesel Engines
When you decide it‘s safe to lift the hood, here’s what you’ll see:
A. Coolant surge tank pressure cap
B. Engine fan(s)
C. Radiator
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 surge 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 A CAUTION:
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.
If there seems to be no leak, start the engine again. See if the fan speed
increases when idle speed
is doubled by pushing the accelerator pedal down.
If
it doesn’t, your vehicle needs service. Turn off the engine.
How to Add Coolant to the Coolant Surge Tank
I NOTICE:
The diesel engine has a specific coolant fill procedure. Failure to
follow this procedure could cause your engine to overheat and be
severely damaged.
If you haven’t found a problem yet, but the coolant level isn’t at the COLD
mark, add a
50/50 mixture of cleun water (preferably distilled) and a proper
antifreeze at the coolant surge tank, but be sure the cooling system,
including the
coolant surge tank pressure cap, is cool before you do it. (See
“Engine Coolant”
in the Index for more information about the proper
coolant mix.)
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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.
A CAUTION:
You can be burned if you spill coolant on hot engine parts.
Coolant contains ethylene glycol and it will burn if the engine
parts are hot enough. Don't spill coolant on
a hot engine.
1. You can remove the coolant surge tank pressure cap when the cooling
system, including the coolant surge tank pressure cap and upper
radiator hose,
is no longer hot. Turn the pressure cap slowly to the left
until it first stops. (Don't press down while turning the pressure cap.)
If you hear a hiss, wait for that to stop. A hiss means there is still some
pressure left.
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