1997 GMC SIERRA cooling

Anti-Lock Brake System Warning Light
ANTI -
LOCK
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 section.
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
Ill This gage shows the engine
1
*\\I‘
00
%,
0
260
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
(lOO°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 ( 125 “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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Air Conditioning
On hot days, open the windows long enough to let hot
air inside escape. This reduces the time it takes for your
vehicle to cool down. Then keep your windows closed
for the air conditioner to work its best.
The recirculation button, between the fan and
temperature knobs, allows the air inside your vehicle to
be recirculated. This setting helps to maximize your air
conditioner’s performance and your vehicle’s 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
HEATER and
DEFROST, the recirculation feature will not function.
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
VENTMEAT 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 (-8OC) 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.
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Ventilation System
For mild outside temperatures 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 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 grrlles,
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.
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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If the water isn’t too deep, then drive through it slowly.
At fast speeds, water splashes on your ignition system
and your vehicle can stall. Stalling can also occur
if you
get your tailpipe under water. And, as long as your
tailpipe is under water, you’ll never be able
to start your
engine. When you go through water, remember that when
your brakes get wet, it may
take you longer to stop.
ki CAU IN:
Driving through rushing water can be dangerous.
Deep water can sweep your vehicle downstream
and you and your passengers could drown.
If it’s
only shallow water, it can still wash away the
ground from under your tires, and
you could lose
traction and roll the vehicle
over. Don’t drive
through rushing water.
After Off-Road Driving
Remove any brush or debris that has collected on
the underbody, chassis or under the hood. These
accumulations can be
a fire hazard.
After operation
in mud or sand, have the brake linings
cleaned and checked. These substances can cause
glazing and
uneven braking. Check the body structure,
steering, suspension, wheels, tires and exhaust system
for damage. Also, check
the fuel lines and cooling
system for any leakage.
Your vehicle will require more frequent service due to
off-road use. Refer to the Maintenance Schedule for
additional information.
See “Driving Through Water”
in the Index for more
information on driving through water.
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If you drive regularly in steep country, or if you’re
planning to visit there, here are some tips
that can make
your trips safer and more enjoyable. (See “Off-Road
Driving” in the Index for information about
driving off-road.)
0 Keep your vehicle in good shape. Check all fluid
levels and also
the brakes, tires, cooling system and
transmission. These
parts can work hard on
mountain roads.
0 Know how to go down hills. The most important
thing
to know is this: let your engine do some of the
slowing down. Shift to a lower gear when you go
down a steep or long hill.
If you don’t shift down, your brakes could get
so hot that they wouldn’t work well. You would
then have poor braking or even none going
down a hill. You could crash. Shift down to let
your engine assist your brakes on a steep
downhill slope.
7-
Coasting downhill in NEUTRAL (N) or with the
ignition
off is dangerous. Your brakes will have to
do all the work of slowing down. They could get
so hot that they wouldn’t work well. You would
then have poor braking or even none going down
a hill.
You could crash. Always have your engine
running and your vehicle in gear when you
go downhill.
0
0
0
0
Know how to go uphill. You may want to shift down
to
a lower gear. The lower gears help cool your engine
and transmission,
and you can climb the hill better.
Stay
in your own lane when driving on two-lane
roads in hills or mountains. Don’t swing wide
or cut
across the center
of the road. Drive at speeds that let
you stay in your own lane.
As you go over the top of a hill, be alert. There could be
something
in your lane, like a stalled car or an accident.
You may see highway signs on mountains that warn of
special problems. Examples are long grades, passing or
no-passing zones, a falling rocks area or winding
roads. Be alert
to these and take appropriate action.
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When You Are Ready to Leave After
Parkine
on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
Start your engine;
Shift into a gear; and
Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important
in trailer
operation are automatic transmission fluid (don’t
overfill), engine oil, axle lubricant, belt, cooling system
and brake adjustment. Each
of these is covered in this
manual, and
the Index will help you find them quickly.
If you’re trailering, it’s a good idea to review these
sections before you start your trip.
Trailer Wiring Harness
A seven-wire harness is stored under the rear end of
your vehicle, between
the frame rails. An electrical
connector will need to be installed at the trailer end of
the harness, by a qualified electrical technician. For
additional trailer wiring and towing information please
consult your
GM dealer. Securely attach the harness to
the trailer, then tape or strap
it to your vehicle’s frame
rail. Be sure you leave it loose enough
so the wiring
won’t bind or break when turning with the trailer, but
not
so loose that it drags on the ground. Store the
harness in its original position. Wrap the harness
together and tie
it neatly so it won’t be damaged. If you
tow
a trailer, your Center High-Mounted Stoplamp
(CHMSL) may not be properly visible from behind.
You
should select a trailer with a CHMSL on it or, if one is
not available, have one installed. See your
GM dealer
about how to connect your vehicle’s wiring
to a
trailer CHMSL.
Check periodically to see that all hitch nuts and bolts
are tight.
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Section 5 Problems on the Road
Here you’ll find what to do about some problems that can occur on the road.
5-2
5-3
5-3
5-8
5-1 1
Hazard Warning Flashers
Other Warning Devices
Jump Starting
Towing Your Vehicle
Engine Overheating (Gasoline Engine) Cooling
System
-- Gasoline Engines
Engine Fan Noise
If a Tire
Goes Flat
Changing
a Flat Tire
If You’re Stuck: In Sand,
Mud, Ice or Snow
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5-2 1
5-2 1
5-22
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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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