2019 GMC SIERRA service

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/13/19
Climate Controls 191
Climate Controls
Climate Control Systems
Climate Control Systems . . . . . 191
Dual Automatic ClimateControl System . . . . . . . . . . . . . 193
Air Vents
Air Vents . . . . . . . . . . . . . . . . . . . . . 197
Maintenance
Passenger Compartment AirFilter . . . . . . . . . . . . . . . . . . . . . . . . 197
Service . . . . . . . . . . . . . . . . . . . . . . . 198
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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/13/19
198 Climate Controls
1. Open the lower glove box doorcompletely.
2. Press the sides of the glovebox 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 0420.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
204 Driving and Operating
Before Driving Off-Road
.Have all necessary maintenance
and service work completed.
. Fuel the vehicle, fill fluid levels,
and check inflation pressure in
all tires, including the spare,
if equipped.
. Read all the information about
four-wheel-drive vehicles in this
manual.
. Remove any underbody air
deflector, if equipped. Re-attach
the air deflector after off-road
driving.
. Know the local laws that apply to
off-road driving.
To gain more ground clearance if
needed, it may be necessary to
remove the front fascia lower air
dam, if equipped. However, driving
without the air dam reduces fuel
economy.Caution
Operating the vehicle for
extended periods without the front
fascia lower air dam installed can
cause improper airflow to the
engine. Reattach the front fascia
air dam after off-road driving.
Loading the Vehicle for
Off-Road Driving
{Warning
. Unsecured cargo on the
load floor can be tossed
about when driving over
rough terrain. You or your
passengers can be struck
by flying objects. Secure the
cargo properly.
. Keep cargo in the cargo
area as far forward and as
low as possible. The
(Continued)
Warning (Continued)
heaviest things should be
on the floor, forward of the
rear axle.
. Heavy loads on the roof
raise the vehicle's center of
gravity, making it more likely
to roll over. You can be
seriously or fatally injured if
the vehicle rolls over. Put
heavy loads inside the
cargo area, not on the roof.
For more information about loading
the vehicle, see Vehicle Load Limits
0 212 and
Tires 0363.
Environmental Concerns
.
Always use established trails,
roads, and areas that have been
set aside for public off-road
recreational driving and obey all
posted regulations.
. Do not damage shrubs, flowers,
trees, or grasses or disturb
wildlife.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
208 Driving and Operating
Caution
Do not drive through standing
water if it is deep enough to cover
the wheel hubs, axles, or exhaust
pipe. Deep water can damage the
axle and other vehicle parts.
If the standing water is not too deep,
drive through it slowly. At faster
speeds, water can get into the
engine and cause it to stall. Stalling
can occur if the exhaust pipe is
under water. Do not turn off the
ignition when driving through water.
If the exhaust pipe is under water,
the engine will not start. When going
through water, the brakes get wet
and it may take longer to stop. See
“Driving on Wet Roads” later in this
section.
After Off-Road Driving
Remove any brush or debris that
has collected on the underbody or
chassis, or under the hood. These
accumulations can be a fire hazard.
Re-install underbody air deflector
and air dam if removed. 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, driveline,
steering, suspension, wheels, tires,
and exhaust system for damage and
check the fuel lines and cooling
system for any leakage.
More frequent maintenance service
is required. See the
Maintenance
Schedule 0420.
Driving on Wet Roads
Rain and wet roads can reduce
vehicle traction and affect your
ability to stop and accelerate.
Always drive slower in these types
of driving conditions and avoid
driving through large puddles and
deep-standing or flowing water.
{Warning
Wet brakes can cause crashes.
They might not work as well in a
quick stop and could cause
pulling to one side. You could
lose control of the vehicle.
After driving through a large
puddle of water or a car/vehicle
wash, lightly apply the brake
pedal until the brakes work
normally.
Flowing or rushing water creates
strong forces. Driving through
flowing water could cause the
vehicle to be carried away. If this
happens, you and other vehicle
occupants could drown. Do not
ignore police warnings and be
very cautious about trying to drive
through flowing water.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Driving and Operating 209
Hydroplaning
Hydroplaning is dangerous. Water
can build up under the vehicle's
tires so they actually ride on the
water. This can happen if the road is
wet enough and you are going fast
enough. When the vehicle is
hydroplaning, it has little or no
contact with the road.
There is no hard and fast rule about
hydroplaning. The best advice is to
slow down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet
weather driving tips include:
.Allow extra following distance.
. Pass with caution.
. Keep windshield wiping
equipment in good shape.
. Keep the windshield washer fluid
reservoir filled.
. Have good tires with proper
tread depth. See Tires0363.
. Turn off cruise control.
Hill and Mountain Roads
Driving on steep hills or through
mountains is different than driving
on flat or rolling terrain. Tips include:
.Keep the vehicle serviced and in
good shape.
. Check all fluid levels, brakes,
tires, and cooling system.
. Shift to a lower gear when going
down steep or long hills.
{Warning
Using the brakes to slow the
vehicle on a long downhill slope
can cause brake overheating, can
reduce brake performance, and
could result in a loss of braking.
Shift the transmission to a lower
gear to let the engine assist the
brakes on a steep downhill slope.
{Warning
Coasting downhill in N (Neutral)
or with the ignition off is
dangerous. This can cause
overheating of the brakes and
loss of steering assist. Always
have the engine running and the
vehicle in gear.
. Drive at speeds that keep the
vehicle in its own lane. Do not
swing wide or cross the
center line.
. Be alert on top of hills;
something could be in your lane
(e.g., stalled car, crash).
. Pay attention to special road
signs (e.g., falling rocks area,
winding roads, long grades,
passing or no-passing zones)
and take appropriate action.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Driving and Operating 221
0 (Stopping the Engine/LOCK/
OFF) :This position turns off the
vehicle. It also locks the ignition, the
transmission, and the steering
column, if equipped with a locking
steering column.
To turn off the vehicle:
1. Make sure that the vehicle is stopped.
2. Shift to P (Park).
3. Continue to hold the brake pedal, then set the parking
brake. See Electric Parking
Brake 0245. 4. Push the key all the way in
toward the steering column,
then turn the key to
LOCK/OFF.
5. Remove the key.
6. Release the brake pedal.
See your dealer if the key can be
removed in any other position.
Retained Accessory Power (RAP)
will remain active. See Retained
Accessory Power (RAP) 0228.
A warning chime will sound when
the driver door is opened and the
key is in the ignition.
If equipped with a locking steering
column, the steering can bind with
the front wheels turned off center,
which may prevent key rotation out
of LOCK/OFF. If this happens, move
the steering wheel from right to left
while turning the key to ACC/
ACCESSORY. If this does not work,
then the vehicle needs service.
{Warning
Turning off the vehicle while
moving may cause loss of power
assist in the brake and steering
systems and disable the airbags.
While driving, turn off the vehicle
only in an emergency.
In an emergency, if the vehicle
cannot be pulled over and must be
turned off while driving: 1. Push the key all the way in toward the steering column,
then turn the key to ACC/
ACCESSORY.
2. Brake using firm and steady pressure. Do not pump the
brakes repeatedly. This may
deplete power assist, requiring
increased brake pedal force.
3. Shift the vehicle to N (Neutral). This can be done while the
vehicle is moving. Continue
braking and steer the vehicle to
a safe location.
4. Come to a complete stop.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
222 Driving and Operating
5. Shift to P (Park).
6. Continue to hold the brakepedal, then set the parking
brake. See Electric Parking
Brake 0245.
7. Push the key all the way in toward the steering column,
then turn the ignition to
LOCK/OFF.
8. Remove the key.
9. Release the brake pedal.
Caution
Use the correct key, make sure it
is all the way in —or pushed all
the way in toward the steering
column when turning off the
vehicle —and turn it only with
your hand.
1 (ACC/ACCESSORY) : This
position allows features such as the
infotainment system to operate
while the vehicle is off. It also
unlocks the steering column,
if equipped with a locking steering column. Use this position if the
vehicle must be pushed or towed.
See
Retained Accessory Power
(RAP) 0228.
From ON/RUN, push the key all the
way in toward the steering column,
then turn the key to ACC/
ACCESSORY.
If the key is left in ACC/
ACCESSORY with the engine off,
the battery could drain and the
vehicle may not start.
A warning chime will sound when
the driver door is opened and the
key is in the ignition.
2 (ON/RUN) : This position can be
used to operate the electrical
accessories and to display some
instrument cluster warning and
indicator lights. This position can
also be used for service and
diagnostics, and to verify the proper
operation of the malfunction
indicator lamp as may be required
for emission inspection purposes.
The switch stays in this position when the engine is running. The
transmission is also unlocked in this
position.
If the key is left in ON/RUN with the
engine off, the battery could drain
and the vehicle may not start.
3 (START) :
This is the position that
starts the engine. When the engine
starts, release the key. The ignition
returns to ON/RUN for driving.
Ignition Positions
(Keyless Access)
Vehicles equipped with Keyless
Access have pushbutton starting.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Driving and Operating 223
The Remote Keyless Entry (RKE)
transmitter must be in the vehicle for
the system to operate. If the
pushbutton start is not working, the
vehicle may be near a strong radio
antenna signal causing interference
to the Keyless Access system. See
Remote Keyless Entry (RKE)
System Operation (Keyless Access)
034 or
Remote Keyless Entry (RKE)
System Operation (Key Access)
0 42.
To shift out of P (Park), the ignition
must be on or in Service Mode, and
the brake pedal must be applied.
{Warning
Turning off the vehicle while
moving may cause loss of power
assist in the brake and steering
systems and disable the airbags.
While driving, only shut the
vehicle off in an emergency. Stopping the Engine/LOCK/
OFF (No Indicator Lights) :
When
the vehicle is stopped, press
ENGINE START/STOP once to turn
the engine off.
If the vehicle is in P (Park), the
ignition will turn off, and Retained
Accessory Power (RAP) will remain
active. See Retained Accessory
Power (RAP) 0228.
If the vehicle is not in P (Park), the
ignition will return to ACC/
ACCESSORY and display the
message SHIFT TO PARK in the
Driver Information Center (DIC).
When the vehicle is shifted into
P (Park), the ignition system will
turn off.
The vehicle may have an electric
steering column lock. The lock is
activated when the ignition is turned
off and either front door is opened.
A sound may be heard as the lock
actuates or releases. The steering
column lock may not release with
the wheels turned off center. If this
happens, the vehicle may not start.
Move the steering wheel from left to right while attempting to start the
vehicle. If this does not work, the
vehicle needs service.
If the vehicle must be shut off in an
emergency:
1. Brake using a firm and steady pressure. Do not pump the
brakes repeatedly. This may
deplete power assist, requiring
increased brake pedal force.
2. Shift the vehicle to N (Neutral). This can be done while the
vehicle is moving. After shifting
to N (Neutral), firmly apply the
brakes and steer the vehicle to
a safe location.
3. Come to a complete stop.
4. Hold the brake pedal down and shift to P (Park). The shift lever
must be in P (Park) to turn the
ignition off.
5. Continue to hold the brake pedal down.
6. Set the parking brake. See Electric Parking Brake 0245.
7. Press ENGINE START/STOP once to turn the ignition off.