2000 GMC ENVOY cooling

For
a More
Detailed Look at
What's Under the Hood
See Section 6
Service Station Guide
Oil Viscosity
Engine Oil
See Section 6
Engine Oil Dipstick
See Section 6Fuel
Use unleaded gas only,
87 Octane or higher.

See Section 6
Cooling System
See Section 5
Hood Release
See Section 6
Windshield Washer
Fluid
See Section 6
Spare Tire Pressure
See Section 6
Battery
See Section 6Tire Pressure
See Section 6
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2-9
Liftgate/Liftglass
CAUTION:
It can be dangerous to drive with the liftgate or
liftglass open because carbon monoxide (CO) gas
can come into your vehicle. You can't see or smell
CO. It can cause unconsciousness and even death.
If you must drive with the liftgate or liftglass
open or if electrical wiring or other cable
connections must pass through the seal between
the body and the liftgate or liftglass:

Make sure all other windows are shut.

Turn the fan on your heating or cooling
system to its highest speed with the setting
on OUTSIDE AIR. That will force outside
air into your vehicle. See ªComfort
Controlsº in the Index.

If you have air outlets on or under the
instrument panel, open them all the way.
See ªEngine Exhaustº in the Index.
Liftgate Release
To release the liftgate or liftglass, you may use
your power door locks or the keyless entry system
described earlier.
The liftglass can be
opened using the
pushbutton on the liftgate
after the driver's door has
been opened using either
the power lock system or
the keyless entry system.
To open the entire liftgate, unlock the doors using
either the power door lock system or the remote keyless
entry system and lift the handle located in the center
of the liftgate.
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3-2
Comfort Controls
With this system, you can control the heating, cooling
and ventilation in your vehicle.
Electronic Climate Control System
Fan Control
The knob on the left side of the climate control panel
controls the fan speed. To manually increase airflow,
turn the knob clockwise. To manually decrease airflow,
turn it counterclockwise.OFF: If the knob is in OFF, outside air will still enter
the vehicle, and will be directed based on the position of
the mode knob.
AUTO: If the knob is in AUTO, the fan speed will vary
as the system maintains the selected temperature.
Temperature Knob
The middle knob on the control panel lets you select the
desired air temperature in your vehicle. This knob will
allow you to adjust the interior air temperature
independently of the function knob setting. Turn the
knob clockwise toward 82 for warmer air. Turn the knob
counterclockwise toward 66 for cooler air.
Full Hot: If you turn the temperature knob past 82
F
(28
C), the system will go into the ªfull hotº mode.
The system will remain at that maximum heating setting
and the fan will blow at the speed the fan knob is set to.
If the fan is in AUTO, it will run at full speed.
Full Cold: If you turn the temperature knob past 66
F
(19
C), the system will go into the ªfull coldº mode.
The system will remain at that maximum cooling setting
and the fan will blow at the speed the fan knob is set to.
If the fan is in AUTO, it will run at full speed.
Choosing either maximum setting will not cause the
system to heat or cool any faster.
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3-5
Remember that in order for the automatic system to
perform well, it needs A/C to provide cooling performance.
Air Conditioning
On hot days, open the windows long enough to let hot
inside air 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.
For quick cool
-down on very hot days, the A/C button
should be enabled and the OUTSIDE AIR button should
not be active.
On cool but sunny days, use BI
-LEVEL A/C to deliver
warm air to the floor and cooler air to the instrument
panel outlets.
When the air conditioner is on, you may sometimes
notice slight changes in your vehicle's engine speed and
power. This is normal because the system is designed
to cycle the compressor on and off to keep the
desired temperature.
Heating
The heater works best if you keep your windows closed
while using it. On cold days, use HEATER with the
temperature knob turned toward the red area. BLEND is
useful in cool weather when you have fog or ice on the
windshield or side windows.
If you use the optional engine coolant heater before
starting your engine, your heating system will produce
warmer air faster to heat the passenger compartment in
cold weather. See ªEngine Coolant Heaterº in the Index.
Defogging and Defrosting
On cool, humid days, use BLEND to keep the
windshield and side windows clear.
Use DEFROST to remove fog or ice from the
windshield quickly in extreme humid or cold conditions.
Turn the temperature knob toward the red area and
move the fan control toward the red area.
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3-6 Rear Window Defogger
The lines you see on
the rear window warm
the glass.
For best results, clear the window of as much snow or
ice as possible before using the rear window defogger.
To turn on the rear window defogger, find the button
marked REAR with the defog symbol on the lower right
corner of your climate control system. Press the button
until the light in the switch comes on, then release it.
It will only work if the ignition switch is turned to RUN.
Pressing the REAR button on your climate control
system will also activate your heated outside mirrors.
This will help to keep ice, snow and condensation
from collecting on your mirror surfaces.The rear window defogger will stay on for five to seven
minutes, then turn off. If you need additional warming
time, turn it on again. You can turn the defogger off at
any time by pressing the button.
Do not attach a temporary vehicle license, tape or decals
across the defogger grid on the rear window.
NOTICE:
Don't use a razor blade or something else sharp
on the inside of the rear window. If you do, you
could cut or damage the warming grid, and the
repairs wouldn't be covered by your warranty.
Ventilation System
For mild outside temperatures when little heating or
cooling is needed, use PANEL with the OUTSIDE AIR
button enabled to direct outside air through your vehicle.
Airflow is through the instrument panel outlets.
Your vehicle's ventilation system supplies outside air to
the inside of your vehicle when it is moving. When the
vehicle is not moving, you can get outside air to flow
through by selecting any mode and any fan speed.
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4-28 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.
Driving at Night
Night driving is more dangerous than day driving.
One reason is that some drivers are likely to be
impaired
-- by alcohol or drugs, with night vision
problems, or by fatigue.
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4-37
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 ªOff
-Road
Drivingº in the Index for information about
driving off
-road.)

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.

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.
CAUTION:
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.
CAUTION:
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.

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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4-52 Driving with a Trailer
CAUTION:
If you have a rear-most window open and you
pull a trailer with your vehicle, carbon monoxide
(CO) could come into your vehicle. You can't see
or smell CO. It can cause unconsciousness or
death. (See ªEngine Exhaustº in the Index.)
To maximize your safety when towing a trailer:

Have your exhaust system inspected for
leaks, and make necessary repairs before
starting on your trip.

Keep the rear
-most windows closed.

If exhaust does come into your vehicle
through a window in the rear or another
opening, drive with your front, main
heating or cooling system on and with the
fan on any speed. This will bring fresh,
outside air into your vehicle. Do not use
RECIRCULATION because it only
recirculates the air inside your vehicle.
(See ªComfort Controlsº in the Index.)
Towing a trailer requires a certain amount of experience.
Before setting out for the open road, you'll want to get
to know your rig. Acquaint yourself with the feel of
handling and braking with the added weight of the
trailer. And always keep in mind that the vehicle you
are driving is now a good deal longer and not nearly as
responsive as your vehicle is by itself.
Before you start, check the trailer hitch and platform
(and attachments), safety chains, electrical connector,
lamps, tires and mirror adjustment. If the trailer has
electric brakes, start your vehicle and trailer moving and
then apply the trailer brake controller by hand to be sure
the brakes are working. This lets you check your
electrical connection at the same time.
During your trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer brakes
are still working.
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