1993 GMC SIERRA heater

When your engine is cold, let it run for a few minutes before you move your
vehicle. This lets oil pressure build up. Your engine will sound louder when
it's cold.
NOTIP
-
If you're not in an idling vehicle and the engine overheats, you wouldn't
there to see the coolant temperature gage. This could damage your
hicle. Don't let vour enaine run when you're not
in vour vehicle.
Cold Weather Starting (Diesel Engine)
The following tips will help you get good starting in cold weather.
Use
SAE IOW-30 oil when the outside temperature drops below freezing.
When the outside temperature drops below
0°F (-18"C), use your engine
block heater.
If you park your vehicle in a garage, you shouldn't need to use \
the block
heater until the garage temperature goes below
0°F (-18"C), no matter how
cold it is outside.
To use the engine block 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:
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CAUTION
Plugging the cord into an ungrounded outlet could cause an ele\
ctrical
shock.
Also, the wrong kind of extension cord could overheat and
cause a fire. You could be seriously injured. Plug the cord into a
properly grounded three-prong
11 0-volt outlet. If the cord won’t reach,
use a heavy-duty three-prong extension cord rated for at least \
15
amps.
1 NOTICE
1 After you’ve used the block heater, be sure to store the cord in th~~~~
manner it was, to help keep it away from moving engine parts.\

If YOU
don’t, it could be torn and damaged.
~p@&%?yl~
How long should you keep tne MOCK neater plugged in? The answer depends
on the weather, the kind
of oil ,you have, and some other things. Follow this-
chart.
,.
ENGINE BLOCK HEATER USAGE”
Viscosity . 32’ $0 0°F ’ 0’ to -10°F ‘Belaw -1 0°F
Grade Oil (0” to &I S‘C) ’ ’ (-18’ to. -23°C) (B&w -23°C)
SAE Not Two Eight Hours
I OW-30 Required Hours or Overnight
SAE . Nit ’ . Two Eight Hours
15W-40 f3equired Hours or Overnight
..
* The times listed are minimum. times. It will not harm &her
the block heater
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or the vehicle to leave it plugged in longer than the times stated. 3
For best results in cold weather, use Number I-D diesel fuel or a “winterized”
Number
2-D fuel.
If 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”
m the Index).
If you’re not out of fuel, and your engine won’t start, do this:
Turn y6ur ignition key
to Run. .Make sure that the GLOW PLUGS light is out.
Then turn
the ignition key to Stkrt while you ‘push the accelerator pedal
down.
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. If the light. doesn’t go off, wait a few seconds, then try staiting 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 out and you know your batte\
ries are
charged, but your engine still won’t start, your vehicle nee\
ds 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.
NOTICE
Don’t use starting “aids” such as ether or gasoline, in the m~v intakc They
could damage your engine.
..- - .- * K2214
In very cold weather, 0°F (-18°C) or colder, if you have an engine block
heater, it can help. You’ll get easier starting and better fuel economy during
engine warm-up.
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Features & Controls
To use the block heater:
1.
Turn off the engine.
2. Open the hood and unwrap the electrical cord.
3. Plug it into a normal, grounded 110-volt outlet.
Plugging the cord into an ungrounded outlet could cause an electrical
- shock. Also, the wrong extension cord could overheat and cause a
fire. You could be seriously injured. Plug the cord into a properly
grounded three-prong 110-volt outlet.
If the cord won’t reach, use a
! heavy-duty three-prong extension cord rated for at least 15 amps.
After you’ve used the block 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.
How long should you keep the block heater plugged in? The ans\
wer depends
on the weather, the kind of oil you have, and some other thi\
ngs. Instead of
trying to list everything here, we ask that you contact a Gen\
eral Motors
dealer in the area where you’ll be parking your vehicle. Th\
e dealer can give
you the best advice for that particular area.
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Comfort Controls & Audio Systems
Section
?
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 system
supplied with your vehicle.
For explanation of vehicle symbols in this secrlon, reTer to “Vehicle
Symbols” in Section 0.
Comfort Control System ........................................................................\
............... 3-2
Flow-Through Ventilation System
..................................................................... 3-2
Heating System (Without Air Conditioning)
..................................................... 3-4
Heater Output
........................................................................\
............................ 3-5
Electronic Heating/Air Conditioning System ..................................................... 3-5
Rear Window Defogger
........................................................................\
............. 3-8
Audio Systems
........................................................................\
............................... 3-9
FM Stereo ........................................................................\
.................................. 3-9
AM
....... . ... . . . . . , .. . . . . . . . . . . .. ... .. .. . . . . . . .. . . . . . ... . .. .. . .. ,. . . . . , . . , . . . . .. . . .. ... .. .. . . . . . . , . . . . ... . . . .... . .. . . . . . .3-9
AM Stereo
............................................. ........................................................... 3-1 0
How to Operate Your AM ETR@Radio ......................................................... 3-10
How to Operate Your AM-FM Stereo Audio System
and Cassette Deck
.II..I.I..I.I...................................I...........I...........\
.............. 3-11
How to Operate Your AM-FM Stereo Audio System
and Cassette Deck with Equalizer
.............,.,.,...................,........................... 3-14
Care of Your Cassette Tape Player
............................................................... 3-18
Fixed Mast Antenna
.................................. ...................................................... 3-1 8
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Comfort Controls & Audio Systems
Comfort Control System
Flow-Through Ventilation System
K2302
Your vehicle's flow-through 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
valves. Outside air will also enter the vehicle when the heate\
r or the air
conditioning fan is running.
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 wind\
ows.
When you enter a vehicle in cold weather, turn the blower fan to
HI for
a few moments before driving
off. This helps clear the intake ducts of
snow and moisture, and reduces the chance of fogging the insid\
e of
your windows.
Keep the air path under the front seats clear of objects. This helps air
to circulate throughout your vehicle.
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Comfort Conhvls & Audio Systems
Heating System (Without Air Conditioning)
K2441
If your vehicle does not have air conditioning, this is what your heat\
ing
system will
look like.
Fan Knob
The knob on the right has four positions. To increase the air flow, turn it
toward
(t). To decrease the air flow, turn it toward (-).
Temperature Lever
The bottom lever lets you select the temperature of the air flowing into your
vehicle. Move the lever right toward
(t) for warmer air. Move the lever left
toward
(-) for cooler air.
Function Lever
The top lever can be moved to three different heating function\
s.
Defrost (Right): This setting operates the defroster. Heated air comes out
near the windshield. Use this when you get fog
or ice on the windshield.
Heater (Center): Heated air comes out near the floor. This is best for cold
weather.
Vent (Left): The air comes out at the vents on your instrument panel and
at your front side windows.
Placing the lever between positions sends air out both vents.
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Heater Output
Optional Engine Block Heater
If your engine is equipped with an optional engine block heater, you can use
it during initial start-up in cold weather (20”F,
-8”C, or lower) to help heat the
passenger compartment faster. Because an engine block heater war\
ms the
engine coolant, your vehicle’s heating system can provide som\
e heat as soon
as you start the engine.
The use
of an engine block 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 Block
Heater” in the Index.
Diesel Engine
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
low. See “Engine Coolant’’ in the Index to find out how to
check your coolant level.
Electronic HeatingAir Conditioning System
Function Display
K2305
If your vehicle has air conditioning, your heating/air conditioning \
system will
look like this.
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