2003 GMC ENVOY cooling system

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 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 and select the
control setting that will force outside air
into your vehicle. See ªClimate Control
Systemº 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 unlock the liftgate, you may use the power door
locks or the keyless entry system described earlier.
On some vehicles the liftglass will also unlock when the
liftgate is unlocked. Press the pushbutton on the
liftglass to open it.
To open the entire liftgate, lift the handle located in the
center of the liftgate. If you open the liftgate, the
liftgate module will lock the liftglass after a one to two
second delay.
Emergency Release for Opening
Liftgate
1. Remove the trim plug to expose the access hole in
the trim panel.
2. Use a tool to reach through the access hole in the
trim panel.
3. Pry the left release lever up to the unlock position.
Pry the right release lever up to unlatch the liftgate.
4. Reattach the trim plug.
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Climate Controls
Dual Climate Control System
With this system you can control the heating, cooling
and ventilation for your vehicle.
9(Fan):Turn the left knob clockwise or
counterclockwise to increase or decrease the fan speed.
If the knob is in off mode, outside air will still enter the
vehicle, and will be directed based on the position of the
mode knob. The temperature can still be adjusted
using the temperature knob.
Turn the right knob clockwise or counterclockwise to
direct the air¯ow inside of your vehicle.To change the current mode, select one of the following:
H(Vent):This mode directs air to the instrument
panel outlets.
)(Bi-Level):This mode directs about half of the air
to the instrument panel outlets; then directs most of
the remaining air to the ¯oor outlets. A little air is
directed toward the windshield and the side window
outlets. Cooler air is directed to the upper vents
and warmer air to the ¯oor outlets.
6(Floor):This mode directs most of the air to the
¯oor outlets with a little air directed to the windshield and
the side window outlets. The recirculation button
cannot be selected while in ¯oor mode.
h(Recirculation):Recirculation mode is used to
recirculate the air inside of your vehicle. When this
button is pressed, an indicator light in the button
will come on to let you know that it is active. Use this
mode to help prevent outside odors and/or dust
from entering your vehicle or to help cool the air inside
of your vehicle more quickly. The air conditioning
compressor will also come on when this mode is
activated. While in recirculation mode, the windows may
fog when the weather is cold and damp. To clear the
fog, select either the blend or defrost mode and increase
fan speed. Recirculation mode shuts off when the
engine is turned off.
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Rear Window Defogger
Your vehicle may have this feature. The lines you see
on the rear window warm the glass.
Press this button to turn the rear window defogger on or
off. An indicator light in the button will come on to let
you know that the rear window defogger is active. The
rear window defogger will automatically turn off
approximately ten minutes after the button is pressed.
If your vehicle is equipped with heated mirrors, this
button will activate them.
Notice:Don't use anything 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. Do not attach a temporary
vehicle license, tape, a decal or anything similar
to the defogger grid.
Outlet Adjustment
Use the air outlets located in the center and on the side
of your instrument panel to direct the air¯ow.
Ventilation System
For mild outside temperatures when little heating or
cooling is needed, use the vent setting to direct outside
air through your vehicle.
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 ¯ow into the front air inlet
grilles, through the vehicle and out the air exhaust
valves.
Outside air will also enter the vehicle when the heater
or the air conditioning is running, unless you have
selected recirculation mode.
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Operation Tips
·
Keep the hood and front air inlets 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 windows.
·When you enter a vehicle in cold weather, turn the
fan knob all the way to the right for a few moments
before driving. This helps clear the intake ducts
of snow and moisture, and reduces the chance of
fogging the inside of your window.
·Keep the air path under the front seats clear of
objects. This helps air to circulate throughout
your vehicle.
·Adding outside equipment to the front of your
vehicle, such as hood-air de¯ectors, may affect the
performance of the heating and air conditioning
system. Check with your dealer before adding
equipment to the outside of your vehicle.
Dual Automatic Climate Control
System
Your vehicle may have the optional dual automatic
climate control system. With this system you can control
the heating, cooling and ventilation for your vehicle.
When your vehicle is ®rst started and the climate control
system is on, or if the climate control system has
been turned on, the display will show the driver's
temperature setting for ®ve seconds. Then it will show
the outside temperature.
9(Off):Press this button to turn off the entire climate
control system. Outside air will still enter the vehicle,
and will be directed to the ¯oor. Press the AUTO button,
the mode button, the fan arrows, or either temperature
knob to turn the system on.
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C(Mode):Press this button to manually select the air
delivery mode to the ¯oor, instrument panel, or
windshield outlets. The system will stay in the selected
mode until the mode button is pressed again or the
AUTO button is pressed.
Driver's Side Temperature Knob:Turn this knob
clockwise or counterclockwise to manually raise or lower
the temperature on the driver's side of the vehicle.
The display will show the temperature setting decreasing
or increasing and the word DRIVER will appear on
the display. This knob can also adjust the passenger's
side temperature setting simultaneously if the two
zones are linked. The words DRIVER and PASS will
then appear on the display.
Passenger's Side Temperature Knob:Turn this knob
clockwise or counterclockwise to manually raise or
lower the temperature on the passenger's side of the
vehicle. The display will show the temperature
setting decreasing or increasing and the word PASS will
appear on the display. The passenger's temperature
setting can be set to match and link to the driver's
temperature setting by pressing and holding the AUTO
button for three seconds. Now, by adjusting the
driver's side temperature setting, the passenger's side
temperature setting will follow and both DRIVER
and PASS will appear on the display. The passenger's
side temperature setting also resets and relinks to
the driver's side temperature setting if the vehicle has
been off for more than two hours.Automatic Operation
AUTO (Automatic):When automatic operation is
active, the system will control the inside temperature,
the air delivery mode, and the fan speed.
Use the steps below to place the entire system in
automatic mode:
1. Press the AUTO button.
When AUTO is selected, the air conditioning
operation and air inlet mode will be automatically
controlled. The air conditioning compressor will run
when the outside temperature is over approximately
40ÉF (4ÉC). The air inlet will normally be set to
outside air. If it's hot outside, the air inlet will
automatically switch to recirculate inside air to help
quickly cool down your vehicle.
2. Set the driver's and passenger's temperature.
To ®nd your comfort setting, start with a 72ÉF (22ÉC)
temperature setting and allow about 20 minutes
for the system to regulate. Turn the driver's or
passenger's side temperature knob to adjust the
temperature setting as necessary. If you choose the
temperature setting of 60ÉF (15ÉC), the system
will remain at the maximum cooling setting. If you
choose the temperature setting of 90ÉF (32ÉC),
the system will remain at the maximum heat setting.
Choosing either maximum setting may not cause
the vehicle to heat or cool any faster.
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Outlet Adjustment
Use the air outlets located in the center and on the side
of your instrument panel to direct the air¯ow.
Ventilation System
For mild outside temperatures when little heating or
cooling is needed, use the vent setting to direct outside
air through your vehicle.
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 ¯ow into the front air inlet
grilles, through the vehicle and out the air exhaust
valves.
Outside air will also enter the vehicle when the heater
or the air conditioning compressor is running, unless you
have pressed the recirculation button.
Operation Tips
·
Keep the hood and front air inlets 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 windows.
·When you enter a vehicle in cold weather, turn the
fan knob all the way to the right for a few moments
before driving. This helps clear the intake ducts
of snow and moisture, and reduces the chance of
fogging the inside of your window.
·Keep the air path under the front seats clear of
objects. This helps air to circulate throughout
your vehicle.
·Adding outside equipment to the front of your
vehicle, such as hood-air de¯ectors, may affect the
performance of the heating and air conditioning
system. Check with your dealer before adding
equipment to the outside of your vehicle.
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DIC Warnings and Messages
Warning messages are displayed on the DIC to notify
the driver that the status of the vehicle has changed and
that some action may be needed by the driver to
correct the condition. More than one message may
appear at one time. They will appear one behind
the other. Some messages may not require immediate
action but you should press the select button to
acknowledge that you received the message and clear it
from the display. Some messages cannot be cleared
from the display because they are more urgent. These
messages require action before they can be removed
from the DIC display. The following are the possible
messages that can be displayed and some information
about them.
ENGINE COOLANT HOT/IDLE ENGINE
If the cooling system temperature gets hot, this
message will appear in the DIC and you will hear a
chime. Stop the vehicle and let the engine idle in
PARK (P) to allow the coolant to reach a safe
temperature. This message will clear when the coolant
temperature drops to a safe operating temperature.
OIL PRESSURE LOW/STOP ENGINE
If low oil pressure levels occur, this message will
be displayed on the DIC. Stop the vehicle as soon as
safely possible and do not operate it until the cause
of the low oil pressure has been corrected. Check your
oil as soon as possible and have your vehicle
serviced.
BATTERY NOT CHARGING
If the battery is not charging during operation, this
message will appear on the DIC. Driving with this
problem could drain your battery. Have the electrical
system checked as soon as possible. Pressing the
select button will acknowledge this message and clear it
from the DIC display.
SERVICE AIR BAG
If there is a problem with the air bag system this
message will be displayed on the DIC. Have a quali®ed
technician inspect the system for problems. Pressing
the select button will acknowledge this message
and clear it from the DIC display.
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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 ®re 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 Ð by alcohol or drugs, with night vision
problems, or by fatigue.
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