1999 GMC ENVOY Owners Manual

3-
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Section 3 Comfort Controls and Audio Systems
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 systems supplied with your vehicle.
3
-2 Comfort Controls
3
-2 Electronic Climate Control System
3
-5 Air Conditioning
3
-5 Heating
3
-5 Defogging and Defrosting
3
-6 Rear Window Defogger
3
-7 Ventilation System
3
-8 Audio Systems
3
-8 Setting the Clock
3
-8AM-FM Stereo with Cassette Tape Player
3
-12 AM-FM Stereo with Compact Disc Player
(If Equipped)3
-16 Rear Seat Audio (RSA)
3
-18 Console-Mounted CD Changer
3
-21 Theft-Deterrent Feature
3
-23 Audio Steering Wheel Controls
3
-24 Understanding Radio Reception
3
-24 Tips About Your Audio System
3
-25 Care of Your Cassette Tape Player
3
-27 Care of Your Compact Discs
3
-27 Care of Your Compact Disc Player
3
-27 Fixed Mast Antenna
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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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Mode Knob - Automatic Operation
The right knob on the control panel allows you to
choose the direction of air delivery. When the system is
set for automatic operation, sensors will control the air
delivery mode. Air will come primarily from the floor or
instrument panel outlets, with some air directed to the
windshield to prevent fogging.
When the system is in AUTO mode, the air conditioning
light will turn on, and the recirculation and outside air
lights turn off. With the system in full auto control (both
the fan and mode knobs in AUTO), you still have the
ability to override any function. However, continually
overriding the outside air or the A/C compressor will limit
the ability of the system to cool the vehicle quickly.
If you push a button for a function which is not
available, the light next to that button will flash three
times to alert you that it's not available.
To find your comfort zone, start with the 74
F (23
C)
setting and allow about 20 minutes for the system to
adjust the temperature if necessary.
With the automatic setting, the air conditioning compressor
automatically cycles when needed to cool the air. In cold
weather, when the system senses the need for heat, the
airflow will be directed out the floor outlets. As the
interior temperature approaches the desired setting, theblower speed will decrease. To maintain interior comfort,
the airflow will adjust between the instrument panel air
outlets and floor outlets. On bright sunny days in cool
weather, the airflow may come out of the air conditioning
and floor outlets (bi
-level mode) to maintain comfort and
prevent stuffiness.
To avoid blowing cold air in cold weather, the system will
delay turning on the fan until warm air is available. The
length of delay depends on the outside air temperature,
engine coolant temperature or the time since the engine
was last started. As the coolant warms up, the blower fan
speed will gradually increase and air will flow from the
heater outlets, with some airflow to the windshield to
prevent fogging under most normal conditions.
If your vehicle is sitting out on a warm day and you
have the fan set on AUTO, the air will first flow out of
the floor air outlets for a few seconds. That is normal.
This is to expel hot air from the air outlets. As the air is
cooled, the airflow will move through the air
conditioning outlets.
Be careful not to put anything over the solar sensor
located around the center of the instrument panel.
This sensor is used by the automatic system to
regulate temperature.
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Mode Knob - Manual Operation
The right knob on the control panel allows you to
choose the direction of air delivery.
You can choose to set the climate control system
operations yourself, or let the system work for you by
placing the system in AUTO mode. See ªMode
Knob
- Automatic Operationº earlier in this section.
PANEL: This setting directs most of the air
through the instrument panel outlets and a small amount
through the floor outlets.
BI-LEVEL: Air is delivered through the heater
floor outlets as well as the instrument panel outlets.
HEATER: This setting directs most of the
warmed air through the heater floor outlets and some air
through the windshield defroster outlets.
BLEND: Airflow is divided equally between the
heater floor outlet and the windshield defroster outlets.
The air conditioning compressor may run to dehumidify
the air to prevent window fogging.
DEFROST: This setting directs most air through
the windshield defroster outlets and some through the
heater outlets. The air conditioning compressor may run
to dehumidify the air to prevent window fogging.
OUTSIDE AIR: Press this button to force the
system to use outside air. Press it again to close off the
outside air.
Pressing the OUTSIDE AIR button will cancel the
RECIRCULATION button.
RECIRCULATION: Press this button to limit the
amount of fresh air entering your vehicle. This is helpful
when you are trying to limit odors entering your vehicle. In
the AUTO mode, the system will use recirculation as
necessary to cool the air. Pressing the recirculation button
will change the operation to a manual mode and the air will
recirculate non
-stop.
RECIRCULATION may be selected with the fan control
in OFF to limit odors, outside air and dust from entering
your vehicle.
Pressing the RECIRCULATION button will cancel the
OUTSIDE AIR button.
A/C: Press this button to turn the air conditioning
on and off. The system will cool and dehumidify the air
inside the vehicle when the A/C light is on.
Air conditioning will be automatically disabled when
the outside temperature drops below a level which air
conditioning is ineffective.
Remember that in order for the automatic system to perform
well, it needs A/C to provide cooling performance.
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3-5 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.
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3-7 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.
You will find air outlets in the center and on the sides of
your instrument panel.You can direct the airflow side
-to-side by rotating the
thumbwheel located in the center of the vent. The vent
can be tilted up and down also. To control the amount of
airflow through the outlets, rotate the thumbwheel
below the vent.
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 windows.

When you enter a vehicle in cold weather, move the
fan control to the right to the highest setting for a
few moments before driving off. This helps clear the
intake ducts of snow and moisture, and reduces the
chance of fogging the inside 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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Audio Systems
Your Delco Electronics audio system has been designed
to operate easily and give years of listening pleasure.
You will get the most enjoyment out of it if you acquaint
yourself with it first. Find out what your Delco
Electronics system can do and how to operate all its
controls, to be sure you're getting the most out of the
advanced engineering that went into it.
Setting the Clock
Press and hold HR until the correct hour appears on the
display. Press and hold MN until the correct minute
appears on the display. To display the clock with the
ignition off, press RECALL or HR/MN and the time
will be displayed for a few seconds. There is an initial
two
-second delay before the clock goes into the
time
-set mode.
AM-FM Stereo with Cassette Tape Player
Included with the AM-FM Stereo with Cassette Tape
Player are six Bose
high performance speakers and a six
channel Bose amplifier. Please see your dealer for details.
Playing the Radio
PWR
-VOL: Press this knob to turn the system on and
off. To increase volume, turn the knob clockwise. Turn
it counterclockwise to decrease volume. The knob is
capable of being rotated continuously.
REAR DSPL: When the primary radio is turned on,
press this button to turn the rear seat audio display on
the primary radio on. Press it again to turn the rear seat
audio display off.
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