1996 GMC SIERRA air condition

Ventilation Tips
Your vehicle has air outlets in the center and on the sides
of your instrument panel. You can move the outlets from
side to side or up and down to direct the
flow of air, or
close the outlets altogether. When
you close an outlet, it
will increase the flow of air coming out of any outlets
that are open. These outlets do not completely
shut off
airflow when
in the closed position.
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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.
When you enter
a vehicle in cold weather, turn the
blower fan to HI for a few moments before driving.
This helps clear the intake ducts
of snow and
moisture, and reduces the chance
of fogging the
inside
of your windows.
Keep the air path under the front seats clear
of
objects. This helps air to circulate throughout
your vehicle.
Defogging and Defrosting
On cool, humid days, use DEFOG to keep the
windshield and side windows clear.
Use DEFROST
to remove fog or ice from the windshield in extremely
humid or cold conditions. Use DEFROST
with the
temperature knob toward
the red area and the fan control
toward
HI.
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2. Get the vehicles close enough so the jumper cables
can reach, but be sure the ve.hicles 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.
To avoid the possibility
of the vehicles rolling,
set the parking brake firmly on both vehicles
involved
in the jump start procedure. Put an
automatic transmission
in PARK (P) or a manual
transmission
in NEUTRAL (N). If you have a
four-wheel-drive vehicle, be sure the transfer
case is not in NEUTRAL
(N).
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or accessory power outlets,
if you have this
option. Turn
off all lamps that aren’t needed as well
as radios. This will avoid sparks and help save both
batteries.
In addition, it could save your radio!
NOTICE:
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If you leave your radio on, it could be badly
damaged. The repairs wouldn’t be covered by
your warranty.
4. Open the hoods and locate the batteries. Find
the positive
(+) and negative (-) terminals 011
each battery.
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.
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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. 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:
I. 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 (0)
or THIRD (3) for automatic transmissions.
If you no longer have the overheat warning, you can drive.
Just to be safe, drive slower
for about 10 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 of
the engine nrzd get everyone nut 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 Tdnk
B. Radiator Pressure Cap
C. Engine Fan(s)
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.
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Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When the
clutch
is engaged, the fan spins fdster 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 andor
high outside temperatures, the
fm 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
fm 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. Fake your foot off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain
lane position, and 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
ITMY 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 tlat, the next part shows how to use your
jacking equipment to change
a flat tire safely.
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If your vehicle is certified to meet California Emission
Standards (indicated on the underhood tune-up label),
it
is designed to operate on fuels that meet California
specifications.
If such fuels are not available in states
adopting California emissions standards,
your vehicle
will operate satisfactorily
on fuels meeting federal
specifications, but emission control system performance
may be affected. The malfunction indicator lamp on
your instrument panel may
turn on and/or your vehicle
may fail a smog-check test.
If this occurs, return to your
authorized GM dealer for diagnosis
to determine the
cause
of failure. In the event it is determined that the
cause
of the condition is the type of fuels used, repairs
may not be covered by
your warranty.
In Canada. some gasolines contain an octane-enhancing
additive called
MMT. If you use such fuels, your
emission control system performance may deteriorate
and the tnalfunction indicator lamp
on your instrument
panel may turn on. If this happens, return to your
authorized
CM dealer for service.
To provide cleaner air, all gasolines are now required to
contain additives that will help prevent deposits from
forming
in your engine and fuel system, allowing your
emission control system
to function properly. Therefore,
you should not have to add anything to the fuel. In
addition, gasolines containing oxygenates, such as ethers
and ethanol, and reformulated gasolines may be
available
in your area to help clean the air. General
Motors recommends that
you use these gasolines if they
comply with the specifications described earlier.
NOTICE:
Your vehicle was not designed for fuel that
contains methanol. Don’t use it.
It can corrode
metal parts
in your fuel system and also damage
plastic and rubber parts. That damage wouldn’t
be covered under your warranty.
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Be careful not to spill gasoline. Clean gasoline from
painted surfxes as soon
as possible. See “Cleaning the
Outside
of Your Vehicle” in the Index.
When you put the cap back
on, turn it to the right until
you hear at least three clicks. Make sure you fully install
the cap. The diagnostic system can determine if the fuel
cap has been
left off or improperly installed. This would
allow
fuel to evaporate into the atmosphere. See
“Malfunction Indicator Lamp” in the Index.
I NOTICE:
If you need a new cap, be sure to get the right
type. Your dealer can get one for you. If you get
the wrong type, it may not fit or have proper
venting, and your fuel tank and emissions system
might be damaged.
Checking Things Under the Hood
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I ! CAUTION:
If your vehicle has air conditioning, the auxiliary
engine fan under the hood can start up and
hjure you even when the engine
is not running.
Keep hands, clothing and tools away from any
underhood electric fan.
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.
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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.
Free movement
of brake calipers and properly torqued
wheel nuts
are necessary to help prevent brake
pulsation. When tires
are rotated, inspect.brake calipers
for movement, brake pads for wear, and evenly torque
wheel nuts in the proper sequence
to GM specifications.
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 drums should be remoQed 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. I
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.
Brake Adjustment
Every time you make a brake stop, your disc brakes
adjust for wear.
If your brake pedal goes down farther than normal, your
rear drum brakes may need adjustment. Adjust them by
backing up and firmly applying the brakes a few times.
Replacing Brake System Parts
The braking system on a modern vehicle is complex. Its
many parts have to be
of top quality and work well
together if the vehicle is to have really good braking.
Vehicles we design and test have top-quality
GM brake
parts
in them, as your vehicle does when it is new. When
you replace parts of your braking system -- for example,
when- your brhke linings wear do.wn and you have
to
haye new ones put in -- be sure you get new genuine
GM replacement parts. If you don’t, your brakes may
no longer work properly. For example,
if someone
puts in brake linings that are wrong for your vehicle,
the balance between your front and rear brakes can
change
-- for the worse. The braking performance
you’ve come to expect can change
in many other ways
if someone puts in the wrong replacement brake parts.
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