2021 GMC SIERRA Dc ac switch

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
184 Infotainment System
To make a call using the Recents menu:1. Touch Phone on the Home Page.
2. Touch Recents.
3. Touch the name or number to call.
Making a Call Using the Keypad
To make a call by dialing the numbers:1. Touch the Phone icon on the Home Page.
2. Touch Keypad and enter a phone number.
3. Touch
#on the infotainment display to
start dialing the number.
Searching Contacts Using the Keypad
To search for contacts using the keypad:
1. Touch the Phone icon on the Home Page.
2. Touch Keypad and enter partial phone numbers or contact names using the
digits on the keypad to search.
Results will show on the right side of the
display. Touch one to place a call.
Accepting or Declining a Call
When an incoming call is received, the
infotainment system mutes and a ring tone
is heard in the vehicle. Accepting a Call
There are two ways to accept a call:
.Pressgon the steering wheel controls.
.Touch Answer on the infotainment
display.
Declining a Call
There are two ways to decline a call:
.Pression the steering wheel controls.
.Touch Ignore on the infotainment display.
Call Waiting
Call waiting must be supported on the
Bluetooth cell phone and enabled by the
wireless service carrier to work.
Accepting a Call
Press
gto answer, then touch Switch on
the infotainment display.
Declining a Call
Press
ito decline, then touch Ignore on
the infotainment display Switching Between Calls (Call Waiting
Calls Only)
To switch between calls, touch Phone on the
Home Page to display Call View. While in
Call View, touch the call information of the
call on hold to change calls.
Three-Way Calling
Three-way calling must be supported on the
Bluetooth cell phone and enabled by the
wireless service carrier to work.
To start a three-way call while in a
current call:
1. In the Call View, touch Add Call to add another call.
2. Initiate the second call by selecting from Recents, Contacts, or Keypad.
3. When the second call is active, touch the merge icon to conference the three-way
call together.
Ending a Call
.Pression the steering wheel controls.
.Touch#on the infotainment display,
next to a call, to end only that call.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Infotainment System 191
.Set Number of Audio Favorites: Touch to
select how many favorites pages can be
viewed from the audio application. The
Auto setting will automatically adjust this
number based on the number of favorites
you have saved. Touch Auto, 5, 10, 15, 20,
25, 30, 35, or 40.
.RDS: This allows the Radio Data System
(RDS) to be turned on or off.
Touch the controls on the infotainment
display to disable or enable.
.HD Radio: This allows HD Radio reception
to be turned on or off.
Touch the controls on the infotainment
display to disable or enable.
.Explicit Content Filter: This setting allows
access to explicit content SiriusXM
channels.
Touch Off or On.
.Manage Phones: Select to connect to a
different phone source, disconnect a
phone, or delete a phone.
.Reset Music Index: This allows the music
index to be reset if you are having
difficulty accessing all of the media
content on your device.
Touch Yes or No.Climate
Touch and the following may display:
.Auto Fan Speed: This setting specifies the
amount of airflow when the climate
control fan setting is Auto Fan.
Touch Low, Medium, or High.
.Air Quality Sensor: This setting switches
the system into Recirculation Mode based
on the quality of the outside air.
Touch Off, Low Sensitivity, or High
Sensitivity.
.Auto Cooled Seats: This setting
automatically turns on and regulates the
ventilated seats when the cabin
temperature is warm.
Touch the controls on the infotainment
display to disable or enable.
.Auto Heated Seats: This setting
automatically turns on and regulates the
heated seats when the cabin temperature
is cool. The auto heated seats can be
turned off by using the heated seat
controls on the center stack.
Touch the controls on the infotainment
display to disable or enable.
.Auto Defog: This setting automatically
turns the front defogger on when the
vehicle engine is started. Touch the controls on the infotainment
display to disable or enable.
.Auto Rear Defog: This setting
automatically turns the rear window
defogger on when the vehicle engine is
started.
Touch the controls on the infotainment
display to disable or enable.
Navigation
Touch and the following may display:
.Set Up My Places
.Map Preferences
.Route Preferences
.Navigation Voice Control
.Traffic Preferences
.Alert Preferences
.Manage History
.Predictive Navigation
.About
See Using the Navigation System 0163.
Phone
Touch and the following may display:
.My Number: Displays the cell phone
number of the Bluetooth connected
device.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Driving and Operating 229
Ignition Positions (Key Access)
0. Stopping the Engine/LOCK/OFF
1. ACC/ACCESSORY
2. ON/RUN
3. START
The ignition switch has four positions.
To shift out of P (Park), the ignition must be
ON/RUN and the brake pedal must be
applied.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 0247.
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)
0 236.
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.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
230 Driving and Operating
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.
5. Shift to P (Park).
6. Push the key all the way in toward the steering column (1), then turn the
ignition to LOCK/OFF (2).
7. Set the parking brake. See Electric
Parking Brake 0247.
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)
0 236.
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)

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
232 Driving and Operating
{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.
ACC/ACCESSORY (Amber Indicator Light) :
This mode allows some electrical accessories
to be used when the engine is off.
With the ignition off, pressing the ENGINE
START/STOP button one time without the
brake pedal applied will place the ignition
system in ACC/ACCESSORY.
The ignition will switch from ACC/
ACCESSORY to off after five minutes to
prevent battery rundown.
ON/RUN/START (Green Indicator Light) : This
mode is for driving and starting. With the
ignition off, and the brake pedal applied,
pressing ENGINE START/STOP button once
will turn the ignition on. Once engine
cranking begins, release the button. Engine
cranking will continue until the engine
starts. See Starting the Engine 0232. Service Mode
This power mode is available for service and
diagnostics, and to verify the proper
operation of the malfunction indicator lamp
as may be required for emission inspection
purposes. With the vehicle off, and the
brake pedal not applied, pressing and
holding the ENGINE START/STOP button for
more than five seconds will place the vehicle
in Service Mode. The instruments and audio
systems will operate as they do when the
ignition is on, but the vehicle will not be
able to be driven. The engine will not start
in Service Mode. Press the ENGINE START/
STOP button again to turn the ignition off.
Starting the Engine
If the vehicle has a diesel engine, see the
Duramax diesel supplement.
Caution
If you add electrical parts or accessories,
you could change the way the engine
operates. Any resulting damage would
not be covered by the vehicle warranty.
See
Add-On Electrical Equipment 0318. Move the shift lever to P (Park) or
N (Neutral). To restart the engine when the
vehicle is already moving, use
N (Neutral) only.
Caution
Do not try to shift to P (Park) if the
vehicle is moving. If you do, you could
damage the transmission. Shift to P (Park)
only when the vehicle is stopped.
Starting Procedure
1. For Key Access vehicles, turn the ignition
key to Start. When the engine starts, let
go of the key. For Keyless Access
vehicles, the RKE transmitter must be in
the vehicle. Press ENGINE START/STOP
with the brake pedal applied. When the
engine begins cranking, let go of the
button.
The driver may observe a minor, and
temporary, brake pedal kickback when
starting the vehicle. This is normal.
The idle speed will go down as the
engine gets warm. Do not race the
engine immediately after starting it.
Operate the engine and transmission
gently to allow the oil to warm up and
lubricate all moving parts.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Driving and Operating 233
When the low fuel warning light is on
and the FUEL LEVEL LOW message is
displayed in the Driver Information
Center (DIC), hold the ignition switch in
the START position to continue engine
cranking.
Caution
Cranking the engine for long periods of
time, by returning the ignition to the
START position immediately after
cranking has ended, can overheat and
damage the cranking motor, and drain
the battery. Wait at least 15 seconds
between each try, to let the cranking
motor cool down.
2. If the engine does not start after five to 10 seconds, especially in very cold
weather (below −18 °C or 0 °F), it could
be flooded with too much gasoline. Try
pushing the accelerator pedal all the way
to the floor and holding it there while
holding the key in START or ENGINE
START/STOP for up to a maximum of
15 seconds. Wait at least 15 seconds
between each try, to allow the cranking
motor to cool down. When the engine
starts, let go of the key or button and
accelerator. If the vehicle starts briefly but then stops again, do the same thing.
This clears the extra gasoline from the
engine. Do not race the engine
immediately after starting it. Operate
the engine and transmission gently until
the oil warms up and lubricates all
moving parts.Stop/Start System
This vehicle has a Stop/Start system to shut
off the engine to help conserve fuel. It has
components designed for the increased
number of starts.
{Warning
The automatic engine Stop/Start feature
causes the engine to shut off while the
vehicle is still on. Do not exit the vehicle
before shifting to P (Park). The vehicle
may restart and move unexpectedly.
Always shift to P (Park), and then turn
the ignition off before exiting the vehicle.
Auto Engine Stop/Start
When the brakes are applied and the vehicle
is at a complete stop, the engine may turn
off. When stopped, the tachometer displays
AUTO STOP. See Tachometer0110. When the brake pedal is released or the
accelerator pedal is pressed, the engine will
restart.
To maintain vehicle performance, other
conditions may cause the engine to
automatically restart before the brake pedal
is released.
Auto Stops may not occur and/or Auto
Starts may occur because:
.The climate control settings require the
engine to be running to cool or heat the
vehicle interior.
.The vehicle battery charge is low.
.The vehicle battery has recently been
disconnected.
.Minimum vehicle speed has not been
reached since the last Auto Stop.
.The accelerator pedal is pressed.
.The engine or transmission is not at the
required operating temperature.
.The outside temperature is not in the
required operating range.
.The vehicle is in any gear other than
D (Drive).
.Tow/Haul Mode or other driver modes
have been selected.
.The vehicle is on a steep hill or grade.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
234 Driving and Operating
.The driver door has been opened or the
driver seat belt has been unbuckled.
.The hood has been opened.
.The Auto Stop has reached the maximum
allowed time.
Auto Stop Disable Switch
If equipped, the automatic engine Stop/Start
feature can be disabled and enabled by
pressing the switch with the
hsymbol.
Auto Stop is enabled each time you start
the vehicle.
When
his illuminated, the system is
enabled.
Engine Heater
If equipped, the engine heater can provide
easier starting and better fuel economy
during engine warm-up in cold weather
conditions at or below −18 °C (0 °F). Vehicles
with an engine heater should be plugged in
at least four hours before starting. An
internal thermostat in the plug-end of the
cord may exist, which will prevent engine
heater operation at temperatures above
−18 °C (0 °F).
{Warning
Do not plug in the engine block heater
while the vehicle is parked in a garage or
under a carport. Property damage or
personal injury may result. Always park
the vehicle in a clear open area away
from buildings or structures.
Base Model shown other models are similar
To Use the Engine Heater
1. Turn off the engine.
2. Check the heater cord for damage. If it is damaged, do not use it. See your dealer
for a replacement. Inspect the cord for
damage yearly.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Driving and Operating 241
During this adaptive shift control process,
shifting might feel different as the
transmission determines the best settings.
When temperatures are very cold, the
transmission's gear shifting could be delayed
providing more stable shifts until the engine
warms up. Shifts could be more noticeable
with a cold transmission. This difference in
shifting is normal.
If equipped with the 2.7L L4 engine, engine
speeds may be increased while driving at
highway speeds while the engine is still
warming up.
L :This position allows selection of a range
of gears appropriate for current driving
conditions. If equipped, see “Range Selection
Mode” underManual Mode 0241.
Caution
Spinning the tires or holding the vehicle
in one place on a hill using only the
accelerator pedal may damage the
transmission. The repair will not be
covered by the vehicle warranty. If the
vehicle is stuck, do not spin the tires.
When stopping on a hill, use the brakes
to hold the vehicle in place.
Manual Mode
Electronic Range Select (ERS)
Caution
Driving with the engine at a high rpm
without upshifting while using Manual
Mode, could damage the vehicle. Always
upshift when necessary while using
Manual Mode.
Electronic Range Select (ERS), or Manual
Mode, allows for the selection of the range
of gear positions. Use this mode when
driving downhill or towing a trailer to limit
the top gear and vehicle speed. The shift
position indicator within the Driver
Information Center (DIC) will display a
number next to the L indicating the highest
available gear. To enter Electronic Range Select or
Manual Mode:
1. With the vehicle in D (Drive), pull back on the shift lever to activate L (Low). The
L in the shift pattern will illuminate in
red, and the D will switch to white.
2. Tap the left steering wheel control to reduce the highest gear available, or the
right control to increase the highest gear
available.
3. To exit, pull back on the shift lever a second time. The D in the shift pattern
will illuminate in red, and the L will
switch to white.
When shifting to L (Low), the transmission
will shift to a preset lower gear range. For
this preset range, the highest gear available
will be displayed next to the L in the DIC.
All gears below that number are available to
use. For example, when 4 (Fourth) is shown
next to the L, 1 (First) through 4 (Fourth)
gears are shifted automatically. To shift to 5
(Fifth) gear, tap the right steering wheel
control or shift into D (Drive).
L (Low) will prevent shifting to a lower gear
range if the engine speed is too high. If the
vehicle speed is not reduced within the time
allowed, the lower gear range shift will not