1996 GMC SIERRA heating

Ashtrays and Cigarette Lighter
Front Ashtray
The front ashtray is located at the bottom of the instrument
panel. Pull
on the notch in the ashtray door to open it.
NOTICE:
If you store paper or other things that burn in
your ashtrays, they could be set on fire by
cigarettes
or other smoking materials. That could
cause
a fire and possibly damage your vehicle. Do
not store papers and other things that burn in
your ashtrays.
To remove the front ashtray, press the retainer spring
and pivot
the ashtray toward you. To replace the ashtray.
place
the bottom part of the ashtray on the pivot bar at
the bottom
of its mounting on the instrument panel.
Then rotate the ashtray
back to its original position.
Rear Ashtray
To use a rear ashtray, if you have them, pull at the top of
the ashtray door to flip the door open.
To remove a rear ashtray. press down on the inside tabs
and open the door fully.
NOTICE:
If you store paper or other things that burn in
your ashtrays, they could be
set on fire by
cigarettes or other smoking materials. That could
cause a fire and possibly damage your vehicle.
Do
not store papers and other things that burn in
your ashtrays.
To use the cigarette lighter, push it in all the way, and let
go. When it’s ready, it will pop back by itself.
NOTICE:
Holding a cigarette lighter in with your hand
while it is heating can make it overload,
damaging the lighter and the heating element.
Just
push the lighter all the way in and let go.
When it’s done, it
will pop back by itself.
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ANTI -
LOCK
Qnti-Lock Brake System Warning Light
With the anti-lock brake.
system, this light will come
on when
you start your
engine and may stay on
for several seconds.
That’s normal.
If the light stays on, or comes on when you’re driving,
your vehicle needs service.
If the regular brake system
warning light isn’t on,
you still have brakes, but you
don’t have anti-lock brakes.
If the regular brake system
warning light is also on, you don’t have anti-lock brakes
and there’s
a problem with your regular brakes. See
“Brake System Warning Light” earlier
in this part.
The anti-lock brake system warning light should come
on briefly when you turn the ignition key to RUN. If the
light doesn’t come on then, have it fixed so it will be
ready to warn
you if there is a problem.
Engine Coolant Temperature Gage
I This gage shows the engine
~ coolant temperature.
It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read 210°F
(100°C) or less. If you are pulling a
load or going up hills, it is normal for the temperature to
fluctuate and approach the 260°F ( 125 “C) mark. If the
gage reaches the 260°F
(I 25 “C) mark, it indicates that
the cooling system is working beyond its capacity.
In “Problems
on the Road,” this manual shows what to
do. See “Engine Overheating” in the Index.
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Section 3 Comfort Controls and Audio Systems
In this section you’ll find out how to operate the comfort
control and audio systems offered
with your vehicle. Be
sure
to read about the particular systems supplied with
your vehicle.
Comfort Controls
Standard Climate Control System
Fan Knob
The knob on the left side of the heating system control
panel controls the fan speed.
The knob has four speed
positions. To increase airflow, move
the knob toward
HI. To decrease airtlow, move it toward LO. To turn the
fan
off, move the knob to OFF.
Temperature Knob
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 clockwise
toward the red area for warmer air. Move the knob
counterclockwise toward the
blue area for cooler air.
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Mode Knob Optional Climate Control System
The right knob on the control panel allows you to
choose
the direction of air delivery. The control knob
can be placed in any position between two mode settings
to blend the
flow of air.
+e
/J VENT: This setting directs air through the
instrument panel outlets.
+’ VENT/HEAT Use this setting to divide airflow
between
the floor outlets and instrument panel outlets.
+iJ HEATB; This setting directs air through the
floor outlets.
6fl DEFOG: This setting directs air to the heater
outlets and toward the windshield.
9 DEFROST: This setting directs air toward
the windshield.
+*
e
(ii3, Fan Knob
The knob on the left side of the heating system control
panel controls the fan speed. The knob has four speed
positions. To increase airflow, move the knob toward
HI. To decrease airflow, 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.
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The A/C button, between the temperature and mode
knobs, allows
the air coming into your vehicle to be
cooled. This setting
is useful for normal cooling on hot
days. When
you use A/C with the recirculation button
pushed
in, turn off recirculation as soon as the vehicle
reaches a comfortable interior temperature.
With the
A/C on, move the temperature knob to MAX
for maximum cooling.
This setting also 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 temperature knob clockwise to place the air
conditioning system
in the normal mode.
Heating
The heater works best if you keep your windows closed
while using
it. On cold days, use the HEATER or
VENT/HEAT setting with the temperature knob in the
red area.
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.
Ventilation System
For mild outside temperature when little heating or
cooling
is needed, use VENT to direct outside air
through
your vehicle. Air will flow through the
instrument panel outlets.
Your vehicle’s ventilation systeril 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 air
exhaust valves.
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 on
the recirculation button, see “Air Conditioning” earlier
in this section.
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Turn Signals When Towing a Trailer
The green arrows on your instrument panel will flash
whenever
you signal a turn or lane change. Properly
hooked up, the trailer lamps will also flash, telling other
drivers you’re about to turn, change lanes or stop.
When towing a trailer, the green arrows
on your
instrument panel will flash for turns even
if the bulbs on
the trailer are burned out. Thus, you may
think drivers
behind
you are seeing your signal when they are not. It’s
important to check occasionally to be sure the trailer
bulbs are
still working.
Driving On Grades
Reduce speed and shift to a lower gear be~m you start
down
a long or steep downgrade. If you don’t shift
down,
you might have to use your brakes so much that
they would get hot and
no longer work well.
On a long uphill grade,
shift down and reduce your
speed
to around 45 mph (70 km/h) to reduce the
possibility
of engine and transmission overheating.
If you have an automatic transmission, you should use
THIRD
(3) (or, as you need to, a lower gear) when
towing a trailer. Operating your vehicle in THIRD
(3)
when towing a trailer will minimize heat build-up and
extend
the life of your transmission
If
you have a manual transmission and you are towing a
trailer,
it’s better not to use FIFTH (5) gear. Just drive in
FOURTH (4) gear (or, as you need to, a lower gear).
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a
lower temperature than at normal altitudes. If
you turn
your engine off‘ immediately after towing at high altitude
on steep uphill grades, your vehicle may show signs
similar
to engine overheating. To avoid this, let the
engine
run while parked (preferably on level ground)
with the automatic transmission
in PARK (P) (or the
manual transmission out
of gear and the parking brake
applied) for a few minutes before turning
the engine off.
If you do get the overheat warning, see “Engine
Overheating’’
in the Index.
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Engine Overheating
(Gasoline Engine)
You will find a coolant temperature gage on your
vehicle’s instrument panel.
If your vehicle has a
diesel engine, see “Engine Overheating” in the Diesel
Engine Supplement.
If Steam Is Coming From Your Engine
A CAUTION:
Steam from an overheated engine can burn you
badly, even if you just open the hood. Stay away
from the engine if you see
or hear steam coming
from it. Just turn it
off and get everyone away
from the vehicle until it cools down. Wait until
there is no sign
of steam or coolant before
opening the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch
fire. You
or others could be badly burned. Stop your engine
if it overheats, and get out of the vehicle until the
engine is cool.
NOTICE:
If your engine catches fire because you keep
driving with no coolant, your vehicle can be
badly damaged. The costly repairs would not be
covered by your warranty.
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Front Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how
often
to check the lubricant and when to change it. See
"Scheduled Maintenance Services"
in the Index.
How to Check Lubricant
If the level is below the bottom of the filler plug hole.
you'll
need to add some lubricant.
If the differential is at operating temperature (warm),
add enough lubricant
to raise the level to the bottom of
the filler plug hole.
If the differential is cold, add enough lubricant to raise
the level
to 1/2 inch (1 2 mm) below the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind
of lubricant to use. See "Recommended Fluids and
Lubricants"
in the Index.
Engine Coolant
The cooling system in your vehicle is filled with new
DEX-COOL
TM (orange-colored, silicate-free) engine
coolant. This coolant is designed
to remain in your
vehicle for
5 years or 100,000 miles (1 66 000 km),
whichever occurs first.
The following explains
your cooling system and how
to add coolant when it is low. If you have a problem
with engine overheating, see "Engine Overheating"
in
the Index.
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