air condition GMC SIERRA 1995 User Guide

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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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.
-
NOTICE:
Ignoring these steps could result in costly damage to your
vehicle that wouldn’t be covered by your vehicle warranty.
Trying to start your vehicle by pushing or pulling it could
damage your vehicle, even if you have a manual transmission.
And if you have an automatic transmission,
it won’t start that
way.
To Jump Start Your Vehicle
1. Check the other vehicle. It must have a 12-volt battery with a negative
ground system.
NOTICE:
If the other system isn’t a 12-volt system with a negative
ground, both vehicles can be damaged.
If you have a diesel engine vehicle with two batteries (or more), you
should know before you begin that, especially in cold weather, you may
not be able to get enough power from a single battery
in another
vehicle to start your diesel engine.
If your vehicle has more than one battery, use the battery that’s on the
passenger side
of the vehicle - this will reduce electrical resistance.
2. Get the vehicles close enough so the jumper cables can reach, but be
sure the vehicles aren’t touching each other.
If they are, it could cause a
ground connection you don’t want.
You wouldn’t be able to start your
vehicle, and the bad grounding could damage
the electrical systems.
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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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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
I A CAUTION:
If your vehicle has air conditioning, the auxiliary electric fan
under the hood can start up even when the engine is not runn\
ing
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.
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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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Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When the clutch is engaged,
the fan spins faster
to provide more air to cool the engine. In most every day
driving conditions the fan is spinning slower and the clutch is
not fully
engaged. This improves fuel economy and reduces fan noise. Under heavy
vehicle loading, trailer towing and/or high outside temperatures, the fan
speed increases as the clutch more fully engages.
So you may hear an
increase
in fan noise. This is normal and should not be mistaken as the
transmission slipping or making extra shifts.
It is merely the cooling system
functioning properly. The fan will slow down when additional cooling is not
required and the clutch partially disengages.
You may also hear this fan noise when you start the engine. It will go away
as the
fan clutch partially disengages.
If a Tire Goes Flat
It’s unusual for a tire to “blow out” while you’re driving, especially if you
maintain your tires properly. If air goes out
of a tire, it’s much more likely to
leak out slowly. But if you should ever have a “blowout,” here are a few tips
about what to expect and what to do:
If a front tire fails, the flat tire will create a drag that pulls the vehicle
toward that side. Take your foot
off the accelerator pedal and grip the
steering wheel firmly, Steer
to maintain lane position, then gently brake to a
stop well out of
the traffic lane.
A rear blowout, particularly on a curve, acts much like a skid and may
require the same correction you’d use in a skid. In any rear blowout, remove
your
foot from the accelerator pedal. Get the vehicle under control by
steering the way
you want the vehicle to go. It may be very bumpy and
noisy, but you can still steer. Gently brake to a stop, well
off the road if
possible.
If a tire goes flat, the next part shows how to use your jacking equipment to
change a flat tire safely.
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Checking Things Under the Hood
Hood Release
To open the hood, first
pull the handle inside
the vehicle.
Then go to the front of
the vehicle and pull up
on the secondary hood
release, located just to
the passenger side
of
the center of the grill.
Lift the hood.
Your vehicle,
if it has
air conditioning, may
have a auxiliary
engine fan in addition
to the belt driven fan.
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A CAUTION:
If your vehicle has air conditioning, the auxiliary engine fan
under the hood can start up and injure you even when the
engine is not running. Keep hands, clothing and tools
away from
any underhood electric fan.
A CAUTION:
Things that burn can get on hot engine parts and start a fire.
These include liquids like gasoline or diesel fuel, oil, coolant,
brake 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 filler caps are on properly. Pull down
the
hood and close it firmly.
Cleaning Your Diesel Engine
I NOTICE:
If you spray or pour water or any other liquid on your engine
when it is warm or hot, or when it
is running, you could cause
serious damage to it.
If you ever clean the engine, clean it only
when it is cold.
Noise Control System
The following information relates to compliance with Federal noise
emission standards for vehicles with a Gross Vehicle Weight Rating
(GVWR)
of more than 10,000 pounds (4 536 kilograms). The Maintenance
Schedule booklet provides information on maintaining
the noise control
system to minimize degradation of the noise emission control system during
the life of your vehicle. The noise control system warranty is given in your
Warranty booklet.
These standards apply only
to vehicles sold in the United States.
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NOTICE:
If you use an improper coolant mix, your engine could overheat
and be badly damaged. The repair cost wouldn’t be covered by
your warranty.
Too much water in the mix can freeze and crack
the engine, radiator, heater core and other parts.
Some conditions. such as air trapped
in the cooling system. can affect the
coolant level
in thc radiator. Check the coolant level when the engine is cold
and
follow the steps under “Adding Coolant“ for the proper way to add
coolant.
If you have to add coolant more than lour timcs a ycar, have your dealer
check your cooling system.
NOTICE:
If you use the proper coolant, you don’t have to add extra
inhibitors or additives which claim to improve the system. These
can be harmful.
Adding Coolant - Gasoline Engine
The coolant reco\wy
tank is located on the
passenger side
at the
rear comer
of the
engine compartment.
To Check Coolant
When your engine is cold, the coolant level should be at the COLD mark, or
a little higher. When your engine is warm, the level should be up to the
HOT mark, or a little higher.
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Brake Wear
Your vehicle has front disc brakes and rear drum brakes. If you have a C
3500 HD model, it has four-wheel disc brakes.
Disc brake pads have built-in wear indicators that make
a high-pitched
warning sound when the brake pads are worn and new pads are needed. The
sound may come and
go or be heard all the time your vehicle is moving
(except when you are pushing on the brake pedal firmly).
I A CAUTION:
The brake wear warning sound means that sooner or later your
brakes won’t work well. That could lead to an accident. Whe\
n
you hear the brake wear warning sound, have your vehicle
serviced.
NOTICE:
Continuing to drive with worn-out brake pads could result in
costly brake repair.
Some driving conditions or climates may cause a brake squeal when the
brakes are first applied or lightly applied. This does not mean something is
wrong with your brakes.
If you have rear drum brakes, they don’t have wear indicators, but if you
ever hear
a rear brake rubbing noise, have the rear brake linings inspected.
Also, the rear brake drum should be removed and inspected each time the
tires are removed for rotation
or changing. When you have the front brakes
replaced, have the rear brakes inspected, too.
Brake linings should always be replaced as complete axle sets.
Brake Pedal Travel
See your dealer if the brake pedal does not return to normal height, or if
there is a rapid increase in pedal travel. This could be a sign of brake
trouble.
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