battery GMC SIERRA 2020 User Guide

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
122 Instruments and Controls
Power Outlets
Accessory power outlets can be
used to plug in electrical equipment,
such as a cell phone or MP3 player.
Rear of Front Center Console
The vehicle has one accessory
power outlet under the climate
control system and one accessory
power outlet on the rear of the
center console, if equipped, or on
the rear of the bench seat,
if equipped.
Lift the cover to access and replace
when not in use.
{Warning
Power is always supplied to the
outlets. Do not leave electrical
equipment plugged in when the
vehicle is not in use because the
vehicle could catch fire and cause
injury or death.
Caution
Leaving electrical equipment
plugged in for an extended period
of time while the vehicle is off will
drain the battery. Always unplug
electrical equipment when not in
use and do not plug in equipment
that exceeds the maximum
15 amp rating.
Certain power accessory plugs may
not be compatible with the
accessory power outlet and could
overload vehicle or adapter fuses.
If a problem is experienced, see
your dealer. When adding electrical equipment,
be sure to follow the proper
installation instructions included with
the equipment. See
Add-On
Electrical Equipment 0322.
Caution
Hanging heavy equipment from
the power outlet can cause
damage not covered by the
vehicle warranty. The power
outlets are designed for
accessory power plugs only, such
as cell phone charge cords.
Power Outlet 110/120-Volt
Alternating Current
If equipped, the vehicle has two
alternating current power outlets.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
Instruments and Controls 135
Uplevel English Shown, BaseLevel and Midlevel Similar
This gauge measures the
temperature of the vehicle's engine
coolant.
While driving under normal
operating conditions, if the needle
moves into the red warning area,
the engine is too hot. Pull off the
road, stop the vehicle, and turn off
the engine as soon as possible.
Voltmeter Gauge
Uplevel Shown, Base Level and Midlevel Similar
When the ignition is on, this gauge
indicates the battery voltage.
When the engine is running, this
gauge shows the condition of the
charging system. The gauge can
transition from a higher to lower or a
lower to higher reading. This is
normal. If the vehicle is operating
outside the normal operating range,
the charging system light comes on.
See Charging System Light 0138. The voltmeter gauge may also read
lower when in fuel economy mode.
This is normal.
Readings outside the normal
operating range can also occur
when a large number of electrical
accessories are operating in the
vehicle and the engine is left idling
for an extended period. This
condition is normal since the
charging system is not able to
provide full power at engine idle. As
engine speeds are increased, this
condition should correct itself as
higher engine speeds allow the
charging system to create maximum
power.
The vehicle can only be driven for a
short time with the readings outside
the normal operating range. If the
vehicle must be driven, turn off all
accessories, such as the radio and
air conditioner.
Readings outside the normal
operating range indicate a possible
problem in the electrical system.
Have the vehicle serviced as soon
as possible.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
138 Instruments and Controls
Warning (Continued)
away. SeeAirbag Readiness
Light 0136 for more information,
including important safety
information.
Charging System Light
The charging system light comes on
briefly when the ignition is turned
on, but the engine is not running, as
a check to show the light is working.
It should go out when the engine is
started.
If the light stays on, or comes on
while driving, there may be a
problem with the electrical charging
system. Have it checked by your
dealer. Driving while this light is on
could drain the battery. When this light comes on, or is
flashing, the Driver Information
Center (DIC) also displays a
message.
If a short distance must be driven
with the light on, be sure to turn off
all accessories, such as the radio
and air conditioner.
Malfunction Indicator
Lamp (Check Engine
Light)
This light is part of the vehicle’s
emission control on-board
diagnostic system. If this light is on
while the engine is running, a
malfunction has been detected and
the vehicle may require service. The
light should come on to show that it
is working when the ignition is on
and the engine is not running. See
Ignition Positions (Keyless Access)
0
208 or
Ignition Positions (Key Access)
0 210.
Malfunctions are often indicated by
the system before any problem is
noticeable. Being aware of the light
and seeking service promptly when
it comes on may prevent damage.
Caution
If the vehicle is driven continually
with this light on, the emission
control system may not work as
well, the fuel economy may be
lower, and the vehicle may not
run smoothly. This could lead to
costly repairs that might not be
covered by the vehicle warranty.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
140 Instruments and Controls
The DLC is under the instrument
panel to the left of the steering
wheel. Connecting devices that are
not used to perform an Emissions
Inspection/Maintenance test or to
service the vehicle may affect
vehicle operation. SeeAdd-On
Electrical Equipment 0322. See
your dealer if assistance is needed.
The vehicle may not pass
inspection if:
. The light is on when the engine
is running.
. The light does not come on
when the ignition is on while the
engine is off.
. Critical emission control systems
have not been completely
diagnosed. If this happens, the
vehicle would not be ready for
inspection and might require
several days of routine driving before the system is ready for
inspection. This can happen if
the 12-volt battery has recently
been replaced or run down, or if
the vehicle has been recently
serviced.
See your dealer if the vehicle will
not pass or cannot be made ready
for the test.
Brake System Warning
Light
MetricEnglish
This light should come on briefly
when the vehicle is turned on. If it
does not come on then, have it fixed
so it will be ready to warn you if
there is a problem.
If the light comes on and stays on at
start up, there is a brake problem.
Have the brake system inspected
right away. If the light comes on while driving,
pull off the road and stop carefully.
If equipped with electric brake
boost, vehicle speed may be limited
when the brake system warning
light comes on. The brake pedal
might be harder to push, or the
brake pedal may go closer to the
floor. It could take longer to stop.
If the light is still on, have the
vehicle towed for service. See
Towing the Vehicle
0424.
{Warning
The brake system might not be
working properly if the brake
system warning light is on.
Driving with the brake system
warning light on can lead to a
crash. If the light is still on after
the vehicle has been pulled off
the road and carefully stopped,
have the vehicle towed for
service.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
156 Instruments and Controls
Vehicle Messages
Messages displayed on the Driver
Information Center (DIC) indicate
the status of the vehicle or some
action that may be needed to
correct a condition. Multiple
messages may appear one after
another.
The messages that do not require
immediate action can be
acknowledged and cleared by
pressing the thumbwheel. The
messages that require immediate
action cannot be cleared until that
action is performed.
All messages should be taken
seriously; clearing the message
does not correct the problem.
If a SERVICE message appears,
see your dealer.
Follow the instructions given in the
messages. The system displays
messages regarding the following
topics:
.Service Messages
. Fluid Levels .
Vehicle Security
. Brakes
. Steering
. Ride Control Systems
. Driver Assistance Systems
. Cruise Control
. Lighting and Bulb Replacement
. Wiper/Washer Systems
. Doors and Windows
. Seat Belts
. Airbag Systems
. Engine and Transmission
. Tire Pressure
. Battery
Engine Power Messages
ENGINE POWER IS REDUCED
This message displays when the
vehicle's propulsion power is
reduced. A reduction in propulsion
power can affect the vehicle's ability
to accelerate. If this message is on,
but there is no observed reduction in performance, proceed to your
destination. The performance may
be reduced the next time the vehicle
is driven. The vehicle may be driven
while this message is on, but
maximum acceleration and speed
may be reduced. Anytime this
message stays on, or displays
repeatedly, the vehicle should be
taken to your dealer for service as
soon as possible.
Under certain operating conditions,
propulsion will be disabled. Try
restarting after the vehicle has been
off for 30 seconds.
Vehicle Speed Messages
SPEED LIMITED TO XXX KM/
H (MPH)
This message shows that the
vehicle speed has been limited to
the speed displayed. The limited
speed is a protection for various
propulsion and vehicle systems,
such as lubrication, thermal, brakes,
suspension, Teen Driver if
equipped, or tires.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
162 Instruments and Controls
instructions refer to a garage door
opener, but can be used for other
devices.
Do not use the Universal Remote
system with any garage door opener
that does not have the stop and
reverse feature. This includes any
garage door opener model
manufactured before April 1, 1982.
Read the instructions completely
before programming the Universal
Remote system. It may help to have
another person assist with the
programming process.
Keep the original hand-held
transmitter for use in other vehicles
as well as for future programming.
Erase the programming when
vehicle ownership is terminated.
See“Erasing Universal Remote
System Buttons” later in this
section.
To program a garage door opener,
park outside directly in line with and
facing the garage door opener
receiver. Clear all people and
objects near the garage door. Make sure the hand-held transmitter
has a new battery for quick and
accurate transmission of the
radio-frequency signal.
Programming the Universal
Remote System
For questions or programming help,
see www.homelink.com/gm or call
1-800-355-3515. For calls placed
outside the U.S., Canada, or Puerto
Rico, international rates will apply
and may differ based on landline or
mobile phone.
Programming involves
time-sensitive actions, and may time
out causing the procedure to be
repeated.
To program up to three devices:
1. Hold the end of the hand-held transmitter about 3 to 8 cm (1
to 3 in) away from the
Universal Remote system
buttons with the indicator light
in view. The hand-held
transmitter was supplied by the
manufacturer of the garage
door opener receiver. 2. At the same time, press and
hold both the hand-held
transmitter button and one of
the three Universal Remote
system buttons to be used to
operate the garage door. Do
not release either button until
the indicator light goes from a
slow to a rapid flashing light.
Then release both buttons.
Some garage door openers
may require substitution of
Step 2 with the procedure
under “Radio Signals for Some
Gate Operators” later in this
section.
3. Press and hold the newly programmed Universal Remote
system button for five seconds
while watching the indicator
light and garage door
activation.
.If the indicator light stays on
continuously or the garage
door moves when the
button is pressed, then
programming is complete.
There is no need to
complete Steps 4–6.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
Lighting 165
Lighting
Exterior Lighting
Exterior Lamp Controls . . . . . . . 165
Exterior Lamps OffReminder . . . . . . . . . . . . . . . . . . . 167
Headlamp High/Low-Beam Changer . . . . . . . . . . . . . . . . . . . . 167
Flash-to-Pass . . . . . . . . . . . . . . . . 168
Daytime Running Lamps (DRL) . . . . . . . . . . . . . . . 168
Automatic Headlamp System . . . . . . . . . . . . . . . . . . . . . . 168
Hazard Warning Flashers . . . . . 169
Turn and Lane-Change Signals . . . . . . . . . . . . . . . . . . . . . . 170
Fog Lamps . . . . . . . . . . . . . . . . . . . 170
Task Lighting . . . . . . . . . . . . . . . . . 171
Exterior Cargo Lamps . . . . . . . . 171
Interior Lighting
Instrument Panel Illumination Control . . . . . . . . . . . . . . . . . . . . . . 172
Dome Lamps . . . . . . . . . . . . . . . . . 172
Reading Lamps . . . . . . . . . . . . . . 173
Lighting Features
Entry Lighting . . . . . . . . . . . . . . . . 173
Exit Lighting . . . . . . . . . . . . . . . . . . 173 Battery Load Management . . . 174
Battery Power Protection . . . . . 174
Exterior Lighting Battery
Saver . . . . . . . . . . . . . . . . . . . . . . . 174
Exterior Lighting
Exterior Lamp Controls
The exterior lamp control is on the
instrument panel to the left of the
steering wheel.
O: Turns off the automatic
headlamps and Daytime Running
Lamps (DRL). Turn the headlamp
control to
Oagain to turn the
automatic headlamps or DRL
back on.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
166 Lighting
For vehicles first sold in Canada, off
will only work when the vehicle is in
P (Park).
AUTO :Automatically turns on the
headlamps, parking lamps,
taillamps, instrument panel lights,
roof marker lamps (if equipped),
front/rear sidemarker lamps, and
license plate lamps.
;: Turns on the parking lamps
including all lamps, except the
headlamps and fog lamps,
if equipped.
2: Turns on the headlamps
together with the parking lamps,
taillamps, instrument panel lights,
roof marker lamps (if equipped),
front/rear sidemarker lamps, and
license plate lamps.
For some trim levels and series of
trucks first sold in Canada, the
headlamps may turn on with the
parking lamps."
When the headlamps are turned on
while the vehicle is on, the
headlamps turn off automatically
10 minutes after the ignition is
turned off. When the headlamps are turned on while the vehicle is off,
the headlamps will stay on for
10 minutes before turning off to
prevent the battery from being
drained. Turn the headlamp control
off and then back to the headlamp
on position to make the headlamps
stay on for an additional 10 minutes.
To keep the lamps on for more than
10 minutes, the ignition must be on
or in ACC/ACCESSORY.
K:
If equipped, turns on the task
lighting. See Task Lighting 0171.
IntelliBeam System
If equipped, this system turns the
vehicle's high-beam headlamps on
and off according to surrounding
traffic conditions.
The system turns the high-beam
headlamps on when it is dark
enough and there is no other traffic
present.
This light
bcomes on in the
instrument cluster when the
IntelliBeam system is enabled. Turning On and Enabling
IntelliBeam
To enable the IntelliBeam system,
press the button on the end of the
turn signal lever when the exterior
lamp control is in the AUTO or
2
position. The blue high-beam on
light appears on the instrument
cluster when the high beams are on.
Driving with IntelliBeam
The system only activates the high
beams when driving over 40 km/h
(25 mph).
There is a sensor near the top
center of the windshield that
automatically controls the system.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
174 Lighting
The exterior lamps and dome lamp
remain on for a set amount of time,
then automatically turn off.
The exterior lamps turn off
immediately by turning the exterior
lamp control off.
This feature can be changed. See
Vehicle Personalization0157.
Battery Load
Management
The vehicle has Electric Power
Management (EPM), which
estimates the battery's temperature
and state of charge. It then adjusts
the voltage for best performance
and extended life of the battery.
When the battery's state of charge
is low, the voltage is raised slightly
to quickly bring the charge back up.
When the state of charge is high,
the voltage is lowered slightly to
prevent overcharging. The voltmeter
gauge or the voltage display on the
Driver Information Center (DIC),
if equipped, may show the voltage moving up or down. This is normal.
If there is a problem, an alert will be
displayed.
The battery can be discharged at
idle if the electrical loads are very
high. This is true for all vehicles.
This is because the generator
(alternator) may not be spinning fast
enough at idle to produce all the
power that is needed for very high
electrical loads.
A high electrical load occurs when
several of the following are on, such
as: headlamps, high beams, fog
lamps, rear window defogger,
climate control fan at high speed,
heated seats, engine cooling fans,
trailer loads, and loads plugged into
accessory power outlets.
EPM works to prevent excessive
discharge of the battery. It does this
by balancing the generator's output
and the vehicle's electrical needs.
It can increase engine idle speed to
generate more power, whenever
needed. It can temporarily reduce
the power demands of some
accessories.Normally, these actions occur in
steps or levels, without being
noticeable. In rare cases at the
highest levels of corrective action,
this action may be noticeable to the
driver. If so, a DIC message might
be displayed and it is recommended
that the driver reduce the electrical
loads as much as possible.
Battery Power Protection
This feature shuts off the dome and
reading lamps, if they are left on for
more than 10 minutes after the
ignition is turned off. The cargo
lamp shuts off after 20 minutes. This
prevents the battery from
running down.
Exterior Lighting Battery
Saver
The exterior lamps turn off about
10 minutes after the ignition is
turned off, if the parking lamps or
headlamps have been manually left
on. This protects against draining
the battery. To restart the 10-minute

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
Driving and Operating 199
If it takes time for help to arrive,
when running the engine, push the
accelerator pedal slightly so the
engine runs faster than the idle
speed. This keeps the battery
charged to restart the vehicle and to
signal for help with the headlamps.
Do this as little as possible, to
save fuel.
If the Vehicle Is Stuck
Slowly and cautiously spin the
wheels to free the vehicle when
stuck in sand, mud, ice, or snow.
See“Rocking the Vehicle to Get It
Out” later in this section.
The Traction Control/Electronic
Stability Control can often help to
free a stuck vehicle. See Traction
Control/Electronic Stability Control
0 235. If TC/ESC cannot free the
vehicle, see “Rocking the Vehicle to
Get it Out” following.
{Warning
If the vehicle's tires spin at high
speed, they can explode, and you
or others could be injured. The
vehicle can overheat, causing an
engine compartment fire or other
damage. Spin the wheels as little
as possible and avoid going
above 56 km/h (35 mph).
For information about using tire
chains on the vehicle, see Tire
Chains 0404.
Rocking the Vehicle to Get
It Out
Caution
Do not hold the steering wheel at
full rotation for more than
15 seconds and/or at an elevated
RPM. Damage may occur to the
power steering system and there
may be loss of power steering
assist. Turn the steering wheel left and
right to clear the area around the
front wheels. Then make sure the
wheels are pointed straight ahead.
For four-wheel-drive vehicles, shift
into Four-Wheel Drive High. Turn
the TCS off. Shift back and forth
between R (Reverse) and a forward
gear, spinning the wheels as little as
possible. To prevent transmission
wear, wait until the wheels stop
spinning before shifting gears.
Slowly spinning the wheels in the
forward and reverse directions
causes a rocking motion that could
free the vehicle. If that does not get
the vehicle out after a few tries, it
might need to be towed out. See
Towing the Vehicle
0424. Recovery
hooks can be used, if the vehicle
has them.