1995 CHEVROLET SUBURBAN cooling

A CAUTION:
It can be dangerous to drive with the tailgate glass, tailgate or
rear doors open because carbon monoxide (CO) gas can come
into your vehicle. You can’t see or smell
CO. It can cause
unconsciousness and even death.
If you must drive with the tailgate glass, tailgate or rear doors
open or
if electrical wiring or other cable connections must pass
through the seal between the body and the tailgate glass, tailgate
or rear doors:
Make sure all windows are shut.
Turn the fan on your heating or cooling system to its highest
speed with the setting on any function. Make sure the
recirculation button is not pressed in. That will force outside
air into your vehicle. See “Comfort Controls” in the Index.
If you have air outlets on or under the instrument panel, open
them all the
way.
See “Engine Exhaust” in the Index.
Tailgate Glass and Tailgate
If your vehicle has a tailgate, you must raise the rear glass before lowering
the tailgate.
.. . ...
To open the glass
from
the outside, use
your door key. With
the key
in the lock,
turn the key clockwise
I to release the glass,
then lift it up.
To release the glass from the inside, use the electric tailgate glass release
switch
on the instrument panel. For more information, see “Fdilgate-
Electric Glass Release”
in the Index.
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Before using your vehicle’s air conditioning, open the windows to clear the
vehicle of
hot air.
Using the recirculation function can also help. See “Recirculation Button”
in this section for more information.
The knob on the left side of the heating system control panel controls the
fan speed. The knob has four speed positions. To increase the air flow, move
the knob toward HI.
To decrease the air flow, move it toward LO. To turn
the fan off, move the knob to
OFF. If you have the air conditioner on,
moving the fan knob to OFF also turns off the A/C compressor.
The middle knob
on the control panel lets you select the relative
temperature
of the air flowing into the passenger area of your vehicle. This
knob will allow
you to adjust the relative air temperature independently of
the function knob setting. Move the knob right toward the red area for
warmer air. Move the knob left toward the blue area for cooler air.
With
A/C on, move the knob to MAX for maximum cooling. This setting
puts the system in the recirculation mode and helps to maximize your air
conditioner’s performance and your vehicle’s fuel economy. This setting
also cools the air
the fastest. After the vehicle’s interior reaches a
comfortable temperature, move
the knob clockwise to place the air
conditioning system
in the normal mode.
The right knob on the control panel changes the heatedair conditioning
setting.
VENT
- This setting, with the arrow pointing at the figure’s head, directs
air through the instrument panel vents.
VENT/HEAT
- Use this setting, with the arrows pointing at the figure’s
feet and head, to divide airflow between the heater floor vents and
instrument panel vents.
HEAT
- This setting, with the arrow pointing at the figure’s feet, directs air
through the heater floor vents. This setting
is useful for cold weather.
HEAT/DEFROST
- Use this setting, with the arrow pointing at the figure’s
feet and the defroster symbol near
the figure’s head, to divide airflow
between the heater floor
vents and windshield.
DEFROST
- This setting with the defrost symbol directs air through the
windshield defroster vents. This setting is useful when
you have fog or ice
on the windshield.
The control knob can be placed in any position between two heatedair
conditioning settings to blend the flow of air. The closer the knob
is to a
setting symbol, the more
the air flow will represent that symbol’s air flow
arrows.
RECIRCULATION BUTTON
- This button, between the left and middle
knobs, allows the air inside your vehicle to be recirculated. This setting
helps to maximize your air conditioner’s performance and your vehicle’s
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fuel economy. This setting also cools the air the fastest and can be used to
keep “unwanted odors” and/or dust from entering the vehicle. When using
the air conditioner, turn off recirculation after the vehicle reaches
a
comfortable interior temperature.
When the right knob
on the control panel is between HEAT and DEFROST,
the recirculation feature will not function.
NC - This button, between the middle and right knobs, allows the air
coming into your vehicle
to be cooled and directed through the instrument
panel vents. This setting
is useful for normal cooling on hot days. When you
first
use A/C with the recirculation button pushed in, turn off recirculation
as soon as the vehicle reaches a comfortable interior temperature.
Engine Coolant 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. If you
use the engine coolant heater before starting your engine (in cold weather
(20” F, (-8” C), or lower) your heating system will produce warmer air
faster, to heat
the passenger compartment in cold weather.
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 Heater Output
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 too low. See “Engine Coolant” in the Index to see how to
check your coolant level.
Rear Air Conditioning and Heating Systems (Suburban)
If your vehicle has either or both of these systems, you can increase and
decrease the air flow at the rear vents. Depending
on the system you have
and the setting selected, you can send cooled or heated air to the rear of the
vehicle.
Rear Air Conditioning (Without Rear Heater)
If your vehicle has rear air conditioning (without rear heater), the controls
are located above the front and second seats. The front and rear overhead
controls let
you increase and decrease the air flow at the rear vents.
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After Off-Road Driving
Remove any biush or debris that has collected on the underbody, chassis or
under the hood. These accumulations
can be a fire hazard.
After operation
in mud or sand, have the brake linings cleaned and checked.
These substances
can cause glazing and uneven braking. Check the body
structure, steering, suspension, wheels, tires, and
exhaust system for
damage. Also, check the fuel lines and cooling system for any leakage.
Your vehicle will require more frequent service due to off-road use. Refer
to the Maintenance Schedule
for additional information.
Driving at Night
Night driving is more dangerous than day driving. One reason is that some
drivers are likely to be impaired
- by alcohol or drugs, with night vision
problems,
or by fatigue.
Here are some tips
on night driving.
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Drive defensively.
Don’t drink and drive.
Adjust your inside rearview mirror to reduce the glare from headlamps
behind you.
Since you can’t see as well, you may need to slow down and
keep more
space between you and other vehicles.
Slow down, especially on higher speed roads. Your headlamps can light
up only
so much road ahead.
In remote areas, watch for animals.
If you’re tired, pull off the road
in a safe place and rest.
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There is something about an easy stretch of road with the same scenery,
along with the hum
of the tires on the road, the drone of the engine, and the
rush of the wind against the vehicle that can make you sleepy. Don’t let it
happen to
you! If it does, your vehicle can leave the road in less than a
second,
and you could crash and be injured.
What can you do about highway hypnosis? First, be aware that it can
happen.
Then here are some tips:
0 Make sure your vehicle is well ventilated, with a comfortably cool
interior.
Keep your eyes moving. Scan the road ahead and to the sides. Check
your mirrors and your instruments frequently.
and take a nap, get some exercise, or both. For safety, treat drowsiness
If you get sleepy, pull off the road into a rest, service, or parking area
on the highway
as an emergency.
Hill and Mountain Roads
Driving on steep hills or mountains is different from driving in flat or
rolling terrain.
If you drive regularly in steep country, or if you’re planning to visit there,
here are some tips that can make your trips safer and more enjoyable. (See
“Off-Road Driving”
in the Index for information about driving off-road.)
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Keep your vehicle in good shape. Check all fluid levels and also the
brakes, tires, cooling system and transmission. These parts can work
hard on mountain roads.
Know
how to go down hills. The most important thing to know is this:
let your engine
do some of the slowing down. Shift to a lower gear
when
you go down a steep or long hill.
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Maintenance When Trailer Towing
Your vehicle will need service more often when you’re pulling a trailer. See
the Maintenance Schedule for more on this. Things that are especially
important
in trailer operation are automatic transmission fluid (don’t
overfill), engine oil, axle lubricant, belt, cooling system, an\
d brake
adjustment. Each
of these is covered in this manual, and the Index will help
you find them quickly. If you’re trailering, it’s a good idea to review these
sections before you start your trip.
Check periodically to see
that all hitch nuts and bolts are tight.
Trailer Lighting Systems Wiring
See “Trailer Wiring Harness” in the Index.
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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 ofthe 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.
Cooling System - Gasoline 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
If the coolant inside the coolant recovery tank is boiling, don’t do anything
else until
it cools down.
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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.
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 Recovery Tank
If you haven’t found a problem yet, but the coolant level isn’t at or above
the
COLD mark, add a 50/50 mixture of clean 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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