1997 GMC SIERRA heater

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A CAJTldN:
Snow can trap exhaust gases under your vehicle.
This can cause deadly
CO (carbon monoxide) gas
to get inside.
CO could overcome you and kill
you. You can’t see it or smell it,
so you might not
know
it is in your vehicle. Clear away snow from
around the base of your vehicle, especially
any
that is blocking your exhaust pipe. And check
around again from time to time to be sure snow
doesn’t collect there.
Open
a window just a little on the side of the
vehicle that’s away from the wind. This will help
keep
CO out. Run your engine
only as long as you must. This saves
fuel. When you run the engine, make
it go a little faster
than just idle. That is, push the accelerator slightly.
This uses less fuel for the heat that you get and
it
keeps the battery (or batteries) charged. You will need a
well-charged battery (or batteries) to restart
the vehicle,
and possibly for signaling later on with your headlamps.
Let the heater run for awhile.
If you have
a diesel engine, you may have to run it at a
higher speed to get enough heat. Then, shut the engine
off and close the window almost all the way to preserve
the heat. Start
the engine again and repeat this only
when
you feel really uncomfortable from the cold. But
do it as little as possible. Preserve the fuel as long as
you
can. To help keep warm, you can get out of the vehicle
and do some fairly vigorous exercises every half hour
or
so until help comes.
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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 (@)
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 oflthe
engine and get everyone out
of the vehicle until it
cools down.
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. Radiator Pressure Cap
C. Engine Fan(s)
You may decide
not to lift the hood but to get service
help right away.
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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 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. 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.
I
Heater and radiator hoses, and other engine
parts, can be very hot. Don’t touch them.
If you
do, you can be burned.
Don’t run the engine if there is
a leak. If you run
the engine, it could lose all coolant. That could
cause an engine fire, and you could be burned.
Get any leak fixed before you drive the vehicle.
I NOTICE:
Engine damage from running your engine
without coolant isn’t covered
by your warranty.
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If there seems to be no leak, start the engine again. See
if the fan speed increases when idle speed is doubled by
pushing
the accelerator pedal down. If it doesn’t, your
vehicle needs service. Turn off the engine.
How to Add Coolant to the Coolant
Recovery
Tank -- Gasoline Engines
If you haven’t found a problem yet, but the coolant level
isn’t at or above the COLD mark, add a
50/50 mixture of
clean water (preferably distilled) and DEX-COOL@
(silicate-free) antifreeze at the coolant recovery tank. (See
“Engine Coolant’’
in the Index for more information.)
I
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mix
will. Your vehicle’s coolant warning
system is set for the proper coolant mix.
CAUTION: (Continued) With plain water
or the wrong mix, your engine
could get too hot but you wouldn’t get the
overheat warning. Your engine could catch fire
and you or others could be burned. Use a
50/50
mix of clean water and DEX-COOL@coolant.
I NOTICE:
r
~~
In cold weather, water can freeze and crack the
engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mix.
5-15
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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 (12 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@ engine coolant. This coolant is
designed to remain in your vehicle for
5 years or
150,000 miles (240
000 km), whichever occurs first,
if
you add only DEX-COOL@ extended life coolant.
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.
A 50/50 mixture of water and the proper coolant for
your vehicle will:
0 Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 265 “F (1 29°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
0 Let the warning gages work as they should.
NOTICE:
When adding coolant, it is important that you use
only
DEX-COOL@(silicate-free) coolant.
If coolant other than DEX-COOL@ is added to
the system, premature engine, heater core or
radiator corrosion may result. In addition, the
engine coolant will require change sooner
-- at
30,000 miles (50 000 km) or 24 months,
whichever occurs first. Damage caused by the use
of coolant other than DEX-COOL@ is not
covered by your new vehicle warranty.
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What to Use
Use a mixture of one-half clean water (preferably
distilled) and one-half
DEX-COOL’ coolant which
won’t damage aluminum parts.
If you use this mixture,
you don’t need to add anything else.
A CAUTION:
Adding only plain water to your cooling system
can
be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant
mix will. Your vehicle’s coolant warning
system is set for the proper coolant
mix. With
plain water or the wrong
mix, your engine could
get too hot but you wouldn’t get the overheat
warning. Your engine could catch fire and you or
others could be burned. Use a
50/50 mix of clean
water and
DEX-COOL@ coolant.
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.
If you have to add coolant more than four times a year,
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.
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Name
ECM-B
RR DEFOG IGN-E
Usage
Fuel Pump, PCMNCM
Rear Window Defogger
Auxiliary Fan Relay Coil,
A/C
Compressor Relay, Hot Fuel
Module, Dual Tanks
Name
FUEL SOL
GLOW PLUG
HORN
AUX FAN
ECM-
1
NC
ENG-
1
LIGHTING
BATT
IGN-A
IGN-B ABS
BLOWER STOP/HAZ
Usage
Fuel Solenoid (Diesel Engine)
Glow plugs (Diesel Engine)
Horn, Underhood Lamps
Auxiliary Fan
Injectors,
PCMNCM
Air Conditioning
lgnition Switch,
EGR, Canister
Purge,
EVRV Idle Coast Solenoid,
Heated
02, Fuel Heater
(Diesel Engine), Water Sensor
(Diesel Engine)
Headlamp and Panel Dimmer
Switch,
Fog and Courtesy Fuses
Battery, Fuse Block Busbar
Ignition Switch
Ignition Switch
Anti-Lock Brake Module
Hi Blower Relay
Stoplamps
6-74
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Part C: Periodic Maintenance
Inspections
Listed below are inspections and services which should
be performed at least twice a year (for instance, each
spring and fall). You should let your GM dealer’s
service department or other qualified service center do
these jobs. Make sure any necessary repairs are
completed at once.
Proper procedures to perform these services may be
found
in a GM service manual. See “Service and Owner
Publications’’
in the Index.
Steering and Suspension Inspection
Inspect the front and rear suspension and steering
system for damaged, loose or missing parts, signs of
wear or lack of lubrication. Inspect the power steering
lines
and hoses for proper hook-up, binding, leaks,
cracks, chafing, etc.
Exhaust System Inspection
Inspect the complete exhaust system. Inspect the body
near the exhaust system.
Look for broken, damaged,
missing or out-of-position parts as well as open seams,
holes, loose connections or other conditions which could
cause
a heat build-up in the floor pan or could let
exhaust fumes into the vehicle. See “Engine Exhaust”
in the Index.
Radiator and Heater Hose Inspection
Inspect the hoses and have them replaced if they are
cracked, swollen or deteriorated. Inspect all pipes,
fittings and clamps; replace as needed.
Throttle Linkage Inspection
Inspect the throttle linkage for interference or binding,
and for damaged or missing parts. Replace parts as
needed. Replace any cables that have high effort
or
excessive wear. Do not lubricate accelerator and cruise
control cables.
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