air conditioning GMC SIERRA DENALI 2019 Owners Manual

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/15/18
Introduction 3
{ DangerDanger indicates a hazard with a
high level of risk which will result
in serious injury or death.
{ WarningWarning indicates a hazard that
could result in injury or death.
CautionCaution 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 Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/15/18
In Brief 19
Climate Controls The heating, cooling, and ventilation in the vehicle can be controlled with
these systems.
Climate Control System
1. Fan Control
2. MAX Defrost
3. Air Delivery Mode Controls
4. A/C (Air Conditioning) 5. (TEMP) Temperature Control
6. Recirculation
7. Rear Window Defogger (If
Equipped)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/15/18
20 In Brief
Dual Automatic Climate Control System
1. Driver and Passenger
Temperature Controls
2. MAX Defrost
3. Air Delivery Mode Controls
4. A/C (Air Conditioning)
5. SYNC (Synchronized
Temperature)
6. Recirculation
7. Power Button 8. Fan Control
9. Rear Window Defogger (If
Equipped)
10. AUTO (Automatic Operation)
See Climate Control Systems 0 188
or Dual Automatic Climate Control
System 0 190 (If Equipped). Transmission Range Selection Mode
The Range Selection Mode switch
is on the shift lever.
1. To enable the Range Selection
feature, move the shift lever to
the L (Manual Mode) position.
The current range will appear
next to the L. This is the
highest attainable range with
all lower gears accessible. As
an example, when 5 (Fifth)
gear is selected, 1 (First)
through 5 (Fifth) gears are
available.
2. Press the plus/minus buttons
on the shift lever to select the
desired range of gears for
current driving conditions. See
Manual Mode 0 232 .

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/15/18
188 Climate Controls
Climate Controls Climate Control Systems Climate Control Systems . . . . . 188
Dual Automatic Climate
Control System . . . . . . . . . . . . . 190
Air Vents Air Vents . . . . . . . . . . . . . . . . . . . . . 194
Maintenance Passenger Compartment Air
Filter . . . . . . . . . . . . . . . . . . . . . . . . 194
Service . . . . . . . . . . . . . . . . . . . . . . . 195 Climate Control Systems The heating, cooling, and ventilation in the vehicle can be controlled with this
system.
1. Fan Control
2. MAX Defrost
3. Air Delivery Mode Controls
4. A/C (Air Conditioning)
5. TEMP (Temperature Control)
6. Recirculation
7. Rear Window Defogger (If
Equipped) 9 : Turn clockwise or
counterclockwise to increase or
decrease the fan speed. Turn the
knob all the way counterclockwise
to turn the fan off.
TEMP : Turn clockwise or
counterclockwise to increase or
decrease the temperature inside the
vehicle.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/18/18
Climate Controls 189Air Delivery Mode Controls :
Press
z ,
Y , or
[ to change the
direction of the airflow. Any
combination of the three controls
can be selected. An indicator light
comes on in the selected mode
button.
To change the current mode, select
one or more of the following. An
indicator light will illuminate:
z : Air is directed to the
windshield, outboard a/c outlets,
and side window outlets.
Y : Air is directed to the a/c outlets.
[ : Air is directed to the floor
outlets, with some air directed to the
windshield, outboard a/c outlets,
and side window outlets.
0 MAX : Air is directed to the
windshield and the fan runs at a
higher speed if not already above a
medium fan speed. This mode
overrides the previous mode
selected and clears fog or frost from
the windshield more quickly. When the control is pressed again, the
system returns to the previous mode
setting and fan speed.
For best results, clear all snow and
ice from the windshield before
defrosting.
@ : 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
indicator light will also go on and off
when the system automatically goes
into and out of recirculation mode to
operate more efficiently.
Avoid using recirculation for long
periods of time in cold or damp
conditions. Using recirculation in
cold or damp conditions can result
in window fogging.
A/C : Press to turn the air
conditioning 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.
Rear Window Defogger
1 REAR : If equipped, 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 engine is running.
The defogger turns off if the ignition
is turned off or to ACC/
ACCESSORY.
If equipped with heated outside
mirrors, press
1 REAR to turn
them on or off. See Heated Mirrors
0 58 .
Caution
Using a razor blade or sharp
object to clear the inside rear
window can damage the rear
(Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/15/18
190 Climate Controls Caution (Continued)window defogger. Repairs would
not be covered by the vehicle
warranty. Do not clear the inside
rear window with sharp objects.
Dual Automatic Climate Control System The heating, cooling, and ventilation in the vehicle can be controlled with this
system.
1. Driver and Passenger
Temperature Controls
2. MAX Defrost
3. Air Delivery Mode Controls
4. A/C (Air Conditioning)
5. SYNC (Synchronized
Temperature)
6. Recirculation
7. Power Button 8. Fan Control
9. Rear Window Defogger (If
Equipped)
10. AUTO (Automatic Operation)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/15/18
Climate Controls 191Climate Control Display
1. Driver and Passenger
Temperature Settings
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. See the infotainment
manual.
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 fan speed, air delivery, air
conditioning, and recirculation in
order to heat or cool the vehicle to
the desired temperature.
When AUTO is lit, all four functions
operate automatically. Each function
can also be manually set and the
selected setting is displayed.
Functions not manually set will
continue to be automatically
controlled, even if the AUTO
indicator is not lit.
For automatic operation:
1. Press AUTO.
2. Set the temperature. Allow the
system time to stabilize. Adjust
the temperature as needed for
best comfort.
To improve fuel efficiency and to
cool the vehicle faster, recirculation
may be automatically selected in
warm weather.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/18/18
Climate Controls 193Avoid using recirculation for long
periods of time in cold or damp
conditions. Using recirculation in
cold or damp conditions can result
in window fogging.
A/C : Press to turn the air
conditioning 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.
Rear Window Defogger
1 REAR : If equipped, 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 engine is running.
The defogger turns off if the ignition
is turned off or to ACC/
ACCESSORY. If equipped with heated outside
mirrors, press
1 REAR to turn
them on or off. See Heated Mirrors
0 58 .
CautionUsing 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.
Remote Start Climate Control
Operation : If equipped with remote
start, the climate control system
may run when the vehicle is started
remotely. If equipped with heated or
ventilated seats or a heated steering
wheel, these features may come on
during a remote start. See Remote
Vehicle Start 0 43 , Heated and
Ventilated Front Seats 0 75 , and
Heated Steering Wheel 0 131 . Sensors
The solar sensor, on top of the
instrument panel near the
windshield, monitors the solar heat.
The climate control system uses the
sensor information to adjust the
temperature, fan speed,
recirculation, and air delivery mode
for best comfort.
Do not cover the sensor; otherwise
the automatic climate control system
may not work properly.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/15/18
Climate Controls 1951. Open the lower glove box door
completely.
2. Press the sides of the glove
box door inward and rotate the
door downward to remove. 3. Pull lever on left side of the
filter door and slide left, then
remove the door. Remove the
old filter.
4. Install the new air filter.
5. Reinstall the filter door.
6. Reverse the steps to reinstall
the glove box.
See your dealer if additional
assistance is needed. 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. See
Maintenance Schedule 0 415 .

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/15/18
330 Vehicle Care 3. Connect the vehicle to a
battery charger.
4. Turn the ignition on for Key
Access vehicles or to Service
Only for Keyless Access
vehicles.
See Ignition Positions (Key
Access) 0 217 or Ignition
Positions (Keyless Access)
0 219 .
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 Electronic Control
Module (ECM) to go to sleep, about
2 minutes, and repeat Steps 3-7.
Listen for pump activation and
movement of the control valves
while watching the level of the
coolant in the surge tank. If the tank empties, turn the ignition off,
carefully remove the surge tank cap,
refill to the COLD FILL mark, and
repeat Steps 3-6. The fill and air
removal process will run for
approximately 10 minutes.
How to Add Coolant to the
Coolant Surge Tank for
Gasoline Engines Except L3B If the vehicle has a diesel engine,
see “ Cooling System ” in the
Duramax diesel supplement for the
proper coolant fill procedure.
{ WarningSpilling coolant on hot engine
parts can burn you. Coolant
contains ethylene glycol and it will
burn if the engine parts are hot
enough. { WarningPlain water, or other liquids such
as alcohol, can boil before the
proper coolant mixture will. With
plain water or the wrong mixture,
the engine could get too hot but
there would not be an overheat
warning. The engine could catch
fire and you or others could be
burned.
{ WarningSteam 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.