1996 CHEVROLET SUBURBAN heater

NOTICE:
If you’re not in an idling vehicle and the engine overheats, you
wouldn’t be there to see the coolant temperature gage. This
could damage your vehicle. Don’t let your engine run when
you’re not in your vehicle.
Cold Weather Starting (Diesel Engine)
The following tips will help you get good starting in cold weather.
Use
SAE 1OW-30 oil when the outside temperature drops below freezing.
When the outside temperature drops below
0” F (- 18 O C), use your engine
coolant heater.
If you park your vehicle
in a garage, you shouldn’t need to use the coolant
heater until the garage temperature goes below
0°F (-1 8OC), no matter how
cold it is outside.
To use the engine coolant heater, first turn off the engine. Then open the
hood, unwrap the electrical cord and plug
it in. It uses normal house voltage
(110 volts), but:
I NOTICE:
After you’ve used the coolant heater, be sure to store the cord in
the manner it was, to help keep it away from moving engine
parts.
If you don’t, it could be torn and damaged.
2-17
ProCarManuals.com

How long should you keep the coolant heater plugged in? The answer
depends
on the weather, the kind of oil you have, and some other things.
Follow this chart.
Viscosity/
Oil Grade
SAE
low-30
SAE
15W40
32°F to 0°F
(OOC to -18OC)
Not
Required
Not
Required
0°F to -10°F
(-18” c to
-23 O C)
Two
Hours*
Two
Hours*
Below -10°F
Below
-23 O C
Eight Hours*
or Overnight
Eight Hours*
or Overnight
*The times listed are minimum times.
It will not harm either the coolant
heater or
the vehicle to leave the coolant heater plugged in longer than the
times stated.
See “Diesel Fuel Requirements and
Fuel System” in the Index for
information
on what fuel to use in cold weather.
lf Your Diesel Engine Won’t Start
If you’ve run out of fuel, look at “Running Out of Fuel” (see “Diesel Fuel
Requirements and Fuel System” in the Index).
If you’re
not out of fuel, and your engine won’t start, do this:
Turn your ignition
key to RUN. Make sure that the GLOW PLUGS light is
out. Then IMMEDIATELY
turn the ignition key to START.
If the light doesn’t go off, wait a few seconds, then try starting your engine
again. And, see your dealer
as soon as you can for a starting system check.
If the light comes
on and then goes off and you know your batteries are
charged, but your engine still
won’t start, your vehicle needs service.
If the light does
not come on when the engine is cold, your vehicle needs
service.
If your batteries don’t have enough charge to start your engine, see
“Battery”
in the Index.
Be sure you have the right oil for your engine, and that you’ve changed
the
oil at the proper times. If you use the wrong oil, your engine may be harder
to start.
If the engine starts, runs a short time, then stops, your vehicle needs service.
2-18
ProCarManuals.com

Engine Coolant Heater (Option)
4
m
In very cold weather, 0°F (-1 8 "C) or colder, the engine coolant heater can
help. You'll get easier starting and better fuel economy during engine
warm-up. Usually, the coolant heater should be plugged in
a minimum of
four hours prior
to starting your vehicle.
To use the coolant heater:
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord.
3. Plug it into a normal, grounded 1 IO-volt outlet.
ProCarManuals.com

NOTICE:
After you’ve used the coolant heater, be sure to store the \
cord as
it
was before to keep it away from moving engine parts. If you
don’t, it could be damaged.
How long should you keep the coolant heater plugged in‘? The answer
depends on the weather, the kind of oil
you have, and some other things.
Instead of trying
to list everything here, we ask that you contact your GM
dealer in the area where you’ll be parking your vehicle. The dealer can give
you the best advice for that particular area.
Automatic Transmission
T
There are several different positions for your shift lever.
If your vehicle is equipped with an automatic transmission, it now features
an electronic shift position indicator within
the instrument cluster. This
display must be powered anytime the shift lever
is capable of being moved
out
of the PARK (P) position. This means that if your key is in the OFF
position, but not locked, there will be a small current drain on your battery
which could discharge your battery over a period of time. If you have a need
to leave your key
in the ignition in the OFF position for an extended period
for any reason,
it is recommended that you disconnect the battery cable
from the battery to prevent discharging your battery.
PARK (P) -This locks your rear wheels. It’s the best position to use
when you start your engine because your vehicle can’t move easily.
2-20
ProCarManuals.com

Comfort Controls and Audio Systems
Section
In this section you’ll find out how to operate the comfort control systems
and audio systems offered with your vehicle.
Be sure to read about the
particular system supplied with your vehicle.
Comfort Controls
Heater Controls
If your vehicle does not have air conditioning, your heater controls will look
like this.
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,
3-1
ProCarManuals.com

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.
The right
knob on the control panel changes the heater 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 heater 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.
Heater/Air Conditioning Controls
If your vehicle has air conditioning, your heatedair conditioning controls
will look like this.
3-2
ProCarManuals.com

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
3-3
ProCarManuals.com

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.
3-4
ProCarManuals.com