2021 GMC ACADIA air conditioning

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
2 Introduction
Using this Manual
To quickly locate information about the
vehicle, use the Index in the back of the
manual. It is an alphabetical list of what is
in the manual and the page number where
it can be found.
Danger, Warning, and Caution
Warning messages found on vehicle labels
and in this manual describe hazards and
what to do to avoid or reduce them.
{Danger
Danger indicates a hazard with a high
level of risk which will result in serious
injury or death.
{Warning
Warning indicates a hazard that could
result in injury or death.
Caution
Caution indicates a hazard that could
result in property or vehicle damage.
A circle with a slash through it is a safety
symbol which means“Do not,” “Do not do
this,” or“Do not let this happen.”
Symbols
The vehicle has components and labels that
use symbols instead of text. Symbols are
shown along with the text describing the
operation or information relating to a
specific component, control, message, gauge,
or indicator.
M:Shown when the owner’s manual has
additional instructions or information.
*: Shown when the service manual has
additional instructions or information.
0: Shown when there is more information
on another page — “see page.” Vehicle Symbol Chart
Here are some additional symbols that may
be found on the vehicle and what they
mean. See the features in this manual for
information.
u:
Air Conditioning System
G:Air Conditioning Refrigerant Oil
9:Airbag Readiness Light
!:Antilock Brake System (ABS)
$:Brake System Warning Light
9:Dispose of Used Components Properly
P:Do Not Apply High Pressure Water
B:Engine Coolant Temperature
_:Flame/Fire Prohibited
H: Flammable
[:Forward Collision Alert
R:Fuse Block Cover Lock Location
+:Fuses
j:ISOFIX/LATCH System Child Restraints

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
192 Climate Controls
Climate Controls
Climate Control Systems
Dual Automatic Climate ControlSystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192
Rear Climate Control System . . . . . . . . . . 196
Air Vents
Air Vents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197
Maintenance
Passenger Compartment Air Filter . . . . . 197
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198
Climate Control Systems
Dual Automatic Climate Control System
With this system the heating, cooling, and ventilation in the vehicle can be controlled.
1. Driver Temperature Control
2. A/C (Air Conditioning)
3. Air Delivery Mode Controls
4. Fan Control
5. Defrost
6. Passenger Temperature Control 7. SYNC (Synchronized Temperature)
8. Rear Window Defogger
9. Power Button
10. Air Recirculation
11. AUTO (Automatic Operation)

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Climate Controls 193
Climate Control Display
1. Driver and Passenger TemperatureSettings
2. Fan Control
3. Driver and Passenger Temperature Controls
4. Sync (Synchronized Temperature)
5. Recirculation
6. Air Delivery Mode Controls
7. Auto (Automatic Operation)
8. A/C (Air Conditioning)
9. On/Off (Power) The fan, air delivery mode, air conditioning,
driver and passenger temperatures, and Sync
settings can be controlled by touching
CLIMATE on the infotainment Home Page or
the climate button in the climate control
display application tray. A selection can then
be made on the front climate control page
displayed.
Climate Control Status Display
The climate control status display appears
briefly when the center stack climate
controls are adjusted.
Automatic Operation
The system automatically controls the
following four functions to heat or cool the
vehicle to the desired temperature:
.Fan Speed
.Air Delivery Mode
.Air Conditioning
.Recirculation
When the AUTO indicator light is lit, all four
functions are operating automatically. Each
function can be manually set and the
selected setting will be shown. This cancels
full automatic operation and the AUTO
indicator light turns off. Functions that are
not manually set will continue to be
automatically controlled, although the AUTO
indicator light will not be lit.
To place the system in automatic mode: 1. Press AUTO.
2. Set the driver and passenger temperature.
To find your comfort setting, start with
22 °C (72 °F) and allow the system time
to stabilize. Then adjust the temperature
as needed for best comfort.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
194 Climate Controls
To improve fuel efficiency and to cool the
vehicle faster, recirculation may be
automatically selected in warm weather.
The recirculation light will not come on
when automatically controlled. Press
@to
manually select recirculation; press it again
to select outside air.
Do not cover the solar sensor on the top of
the instrument panel near the windshield.
This sensor regulates air temperature based
on sun load. See “Sensors”later in this
section.
Manual Operation
O: Press to turn the climate control system
on or off. When the system is off, outside
air will be prevented from entering the
vehicle. When the system is on, a button is
pressed, or knob is turned, the climate
control system will turn on and deliver
airflow per the current setting.
9: Turn clockwise or counterclockwise to
increase or decrease the fan speed. Press the
knob to turn the fan off.
Press AUTO to return to automatic
operation. Driver and Passenger Temperature Control :
The temperature can be adjusted separately
for the driver and passenger.
Turn the knob clockwise or counterclockwise
to increase or decrease the driver or
passenger temperature setting.
SYNC :
Press to link the passenger and rear
climate temperature settings, if equipped, to
the driver setting. The SYNC indicator light
will turn on. When the passenger or rear
climate temperature settings are adjusted,
the SYNC indicator light is off.
The driver side or passenger side
temperature display shows the temperature
setting increasing or decreasing.
Air Delivery Mode Control : Press
Y,\,
[, or-to change the direction of the
airflow. An indicator light comes on in the
selected mode button.
Changing the mode cancels the automatic
operation and the system goes into manual
mode. Press AUTO to return to automatic
operation.
Y: Air is directed to the instrument panel
outlets.
\: Air is divided between the instrument
panel and floor outlets. Some air is directed
toward the windshield and side window
outlets.
[: Air is directed to the floor outlets,
with some to the windshield, side window
outlets, and second row floor outlets.
-: This mode clears the windows of fog or
moisture. Air is directed to the windshield,
floor outlets, and side window vents. The
system automatically forces outside air into
the vehicle and the air conditioning
compressor will run, unless the outside
temperature is close to freezing.
0: Press to clear the windshield of fog or
frost more quickly. Air is directed to the
windshield and the side window vents. The
air conditioning compressor also comes on,
unless the outside temperature is below
freezing.
Do not drive the vehicle until all windows
are clear.
See Air Vents 0197.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Climate Controls 195
A/C :Press to turn the air conditioning
system on or off. An indicator light comes
on to show that the air conditioning is
enabled. If the fan is turned off, the air
conditioner will not run. The A/C light will
stay on even if the outside temperatures are
below freezing.
@: Press to turn on recirculation. An
indicator light comes on. Air is recirculated
to quickly cool the inside of the vehicle.
It can also be used to help reduce outside
air and odors that enter the vehicle. The air
conditioning compressor also comes on
when this mode is activated.
Rear Window Defogger
The rear window defogger uses a warming
grid to remove fog from the rear window.
K: Press to turn the rear window defogger
on or off. An indicator light on the button
comes on to show that the rear window
defogger is on.
The rear window defogger only works when
the ignition is on. The defogger turns off if
the ignition is turned to off or ACC/
ACCESSORY.
Caution
Using a razor blade or sharp object to
clear the inside rear window can damage
the rear window defogger. Repairs would
not be covered by the vehicle warranty.
Do not clear the inside rear window with
sharp objects.
Heated Mirror : If equipped with heated
outside mirrors, the mirrors heat to help
clear fog or frost from the surface of the
mirror when the rear window defog button
is pressed. See Heated Mirrors 028.
Remote Start Climate Control Operation :
If equipped with remote start, the climate
control system may run when the vehicle is
started remotely. The rear defog may come
on during remote start based on cold
ambient conditions. The rear defog indicator
light does not come on during a remote
start.
If equipped, the heated seats will turn on if
it is cold outside or the ventilated seats will
turn on if it is hot outside. The heated and
ventilated seat indicator lights may not
come on during a remote start. If equipped,
the heated steering wheel will come on in a remote start if it is cold outside. The heated
steering wheel indicator light may not
come on.
Sensors
The solar sensor, located in the defrost grille
in the middle of the instrument panel,
monitors the solar heat. Do not cover the
solar sensor or the system will not work
properly.
There is also an exterior temperature sensor
behind the front grille. This sensor reads the
outside air temperature and helps maintain
the temperature inside the vehicle. Any
cover on the front of the vehicle, could
cause a false reading in the displayed
temperature.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
198 Climate Controls
Using the climate control system without an
air filter installed is not recommended.
Water or other debris could enter the
system and result in leaks or noises. Always
install a new filter when removing the old
filter.
For more information on filter replacement,
see your dealer.
Service
All vehicles have a label underhood that
identifies the refrigerant used in the vehicle.
The refrigerant system should only be
serviced by trained and certified technicians.
The air conditioning evaporator should never
be repaired or replaced by one from a
salvage vehicle. It should only be replaced
by a new evaporator to ensure proper and
safe operation.
During service, all refrigerants should be
reclaimed with proper equipment. Venting
refrigerants directly to the atmosphere is
harmful to the environment and may also
create unsafe conditions based on
inhalation, combustion, frostbite, or other
health-based concerns.
The air conditioning system requires periodic
maintenance. SeeMaintenance Schedule
0 346.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Vehicle Care 285
6. Verify coolant level after the engine isshut off and the coolant is cold.
If necessary, repeat coolant fill procedure
Steps 1–6.
If the coolant still is not at the proper
level when the system cools down again,
see your dealer.
Caution
If the pressure cap is not tightly installed,
coolant loss and engine damage may
occur. Be sure the cap is properly and
tightly secured.
Automatic Coolant Service Fill (2.0L
Engine Only)
If equipped, this feature assists in filling and
removing air from the cooling system after
service of components or when coolant is
added after being too low.
To activate the fill and air removal process:
1. With a cold system, disconnect the vent line from the port near the cap on the
surge tank. Add coolant to the indicated
mark on the surge tank.
2. Reconnect the vent line to the surge tank and replace the cap on the
surge tank. 3. Connect the vehicle to a battery charger.
4. Put the vehicle in Service Mode. See
Ignition Positions 0213.
5. Turn off the air conditioning.
6. Set the parking brake.
7. At the same time, press the accelerator and the brake for automatic transmission
vehicles for two seconds, then release.
At the end of the cycle, check the coolant
level in the surge tank and add coolant, if it
is low. Turn off the vehicle, allow the Engine
Control Module (ECM) to go to sleep, about
two minutes, and repeat steps 3-7.
Listen for pump activation and movement of
the control valves while watching the level
of the tank. If the tank empties, turn the
ignition off, carefully remove the surge tank
cap, refill to the indicated mark and repeat
steps 3-6. The fill and air removal process
will run for approximately 10 minutes.
Engine Overheating
The vehicle has several indicators to warn of
the engine overheating. There is an engine coolant temperature
gauge on the instrument cluster. See
Engine
Coolant Temperature Gauge 0104. The
vehicle may also display a message on the
Driver Information Center (DIC).
If the decision is made not to lift the hood
when this warning appears, get service help
right away. See Roadside Assistance Program
0 366.
If the decision is made to lift the hood,
make sure the vehicle is parked on a level
surface. Then check to see if the engine
cooling fan is running. If the engine is
overheating, the fan should be running. If it
is not, do not continue to run the engine.
Have the vehicle serviced.
Caution
Do not run the engine if there is a leak
in the engine cooling system. This can
cause a loss of all coolant and can
damage the system and vehicle. Have
any leaks fixed right away.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
286 Vehicle Care
If Steam Is Coming from the Engine
Compartment
{Warning
Steam and scalding liquids from a hot
cooling system are under pressure.
Turning the pressure cap, even a little,
can cause them to come out at high
speed and you could be burned. Never
turn the cap when the cooling system,
including the pressure cap, is hot. Wait
for the cooling system and pressure cap
to cool.
If No Steam Is Coming from the Engine
Compartment
If an engine overheat warning is displayed
but no steam can be seen or heard, the
problem may not be too serious. Sometimes
the engine can get a little too hot when the
vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.
.Idles for long periods in traffic.
If the overheat warning is displayed with no
sign of steam: 1. Turn the air conditioning off. 2. Turn the heater on to the highest
temperature and to the highest fan
speed. Open the windows as necessary.
3. When it is safe to do so, pull off the road, shift to P (Park) or N (Neutral), and
let the engine idle.
If the engine coolant temperature gauge is
no longer in the overheated area, the
vehicle can be driven. Continue to drive the
vehicle slowly for about 10 minutes. Keep a
safe distance from the vehicle in front. If the
warning does not come back on, continue to
drive normally and have the cooling system
checked for proper fill and function.
If the warning continues, pull over, stop, and
park the vehicle right away.
If there is no sign of steam, idle the engine
for three minutes while parked. If the
warning is still displayed, turn off the
engine until it cools down.
Washer Fluid
What to Use
When windshield washer fluid is needed, be
sure to read the manufacturer's instructions
before use. If operating the vehicle in an area where the temperature may fall below
freezing, use a fluid that has sufficient
protection against freezing.
Adding Washer Fluid
Open the cap with the washer symbol on it.
Add washer fluid until the tank is full. See
Engine Compartment Overview
0271 for
reservoir location.
Caution
.Do not use washer fluid that contains
any type of water repellent coating.
This can cause the wiper blades to
chatter or skip.
.Do not use engine coolant (antifreeze)
in the windshield washer. It can
damage the windshield washer system
and paint.
(Continued)