2020 GMC SIERRA instrument cluster

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
304 Driving and Operating
Trailer Lamps
Always check that all trailer lamps
are working at the beginning of each
trip, and periodically on longer trips.
If equipped, the Trailering App will
monitor the RH turn/brake lamp
circuit, LH turn/brake lamp circuit,
running lamp circuit, and reverse
lamp circuits on the trailer. DIC
messages and Trailering App alerts
may be displayed if lighting circuit
issues are detected on the trailer.
Pressing START LIGHT TEST in the
Trailering App automatically
activates the trailer lamps. The
Trailering App is not a substitute for
manually inspecting your trailer
lamps. SeeTrailering App 0310.
Turn Signals When Towing a
Trailer
When properly connected, the trailer
turn signals will illuminate to indicate
the vehicle is turning, changing
lanes, or stopping. When towing a
trailer, the arrows on the instrument cluster will illuminate even if the
trailer is not properly connected or
the bulbs are burned out.
Tow/Haul Mode
For instructions on how to enter
Tow/Haul Mode, see
Driver Mode
Control 0238.
Tow/Haul assists when pulling a
heavy trailer or a large or heavy
load. See Tow/Haul Mode 0226.
Tow/Haul Mode is designed to be
most effective when the vehicle and
trailer combined weight is at least
75% of the vehicle's Gross
Combined Weight Rating (GCWR).
See “Trailer Weight ”under Trailer
Towing 0292.
Tow/Haul Mode is most useful when
towing a heavy trailer or carrying a
large or heavy load:
. Through rolling terrain.
. In stop-and-go traffic.
. In busy parking lots.
Operating the vehicle in Tow/Haul
Mode when lightly loaded or not
towing will not cause damage; however, it is not recommended and
may result in unpleasant engine and
transmission driving characteristics,
heavy or light steering efforts, and
reduced fuel economy.Integrated Trailer Brake
Control System
The vehicle may have an Integrated
Trailer Brake Control (ITBC) system
for use with electric trailer brakes or
most electric over hydraulic trailer
brake systems. These instructions
apply to both types of electric trailer
brakes.
This symbol is on the Trailer Brake
Control Panel on vehicles with an
ITBC system. The power output to
the trailer brakes is proportional to
the amount of vehicle braking. This

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
308 Driving and Operating
To determine whether the electrical
fault is on the vehicle side or trailer
side of the trailer wiring harness
connection:1. Disconnect the trailer wiring harness from the vehicle.
2. Turn the ignition off.
3. Wait 10 seconds, then turn the ignition back to RUN.
4. If the CHECK TRAILER WIRING message reappears,
the electrical fault is on the
vehicle side.
If the CHECK TRAILER WIRING
message only reappears when
connecting the trailer wiring harness
to the vehicle, the electrical fault is
on the trailer side.
SERVICE TRAILER BRAKE
SYSTEM: This message will display
when there is a problem with the
ITBC system. If this message
continues over multiple ignition
cycles, have the vehicle serviced.
If either the CHECK TRAILER
WIRING or SERVICE TRAILER
BRAKE SYSTEM message displays while driving, the ITBC system may
not be fully functional or may not
function at all. When traffic
conditions allow, carefully pull the
vehicle over to the side of the road
and turn the ignition off. Check the
wiring connection to the trailer and
turn the ignition back on. If either of
these messages continues, either
the vehicle or trailer needs service.
A GM dealer may be able to
diagnose and repair problems with
the trailer. However, any diagnosis
and repair of the trailer is not
covered under the vehicle warranty.
Contact your trailer dealer for
assistance with trailer repairs and
trailer warranty information.
Trailer Sway
Control (TSC)
Vehicles with StabiliTrak/Electronic
Stability Control (ESC) have a
Trailer Sway Control (TSC) feature.
Trailer sway is unintended
side-to-side motion of a trailer while
towing. If the vehicle is towing a
trailer and the TSC detects that
sway is increasing, the vehiclebrakes are selectively applied at
each wheel, to help reduce
excessive trailer sway. If equipped
with the Integrated Trailer Brake
Control (ITBC) system, and the
trailer has an electric brake system,
StabiliTrak/ESC may also apply the
trailer brakes.If TSC is enabled, the Traction
Control System (TCS)/StabiliTrak/
ESC warning light will flash on the
instrument cluster. Reduce vehicle
speed by gradually removing your
foot from the accelerator. If trailer
sway continues, StabiliTrak/ESC
can reduce engine torque to help

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
Vehicle Care 351
6. Verify coolant level after theengine is shut off and the
coolant is cold. If necessary,
repeat coolant fill procedure
Steps 1–6.
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.
Engine Overheating
If the vehicle has the Duramax
diesel engine, see the Duramax
diesel supplement.
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. The vehicle has several indicators
to warn of engine overheating.
There is a coolant temperature
gauge in the vehicle's instrument
cluster. See
Engine Coolant
Temperature Gauge 0134.
In addition, there are ENGINE
OVERHEATED STOP ENGINE,
ENGINE OVERHEATED IDLE
ENGINE, and ENGINE POWER IS
REDUCED messages in 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
0 467.
If the decision is made to lift the
hood, make sure the vehicle is
parked on a level surface.
2.7L L4, 4.3L V6, 5.3L V8, and 6.2L
V8 Engines
Check to see if the engine cooling
fans are running. If the engine is
overheating, the fans should be running. If they are not, do not
continue to run the engine and have
the vehicle serviced.
If the engine or transmission detects
an impending hot fluid condition,
then the transmission may force
upshifts to limit temperatures.
Downshifts may also be prevented
in this instance. Normal operation
may continue unless the display
indicates there is a hot condition
and engine should be idled.
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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
Vehicle Care 377
BackThe vehicle may not be equipped
with all of the fuses, relays, and
features shown.
Fuses Usage
F1 Right doors
F2 Left doors
F3 Universal remote system
F4 –
F5 –
F6 Front blower
F8 Lumbar switch
F10 Body control module 6/Body control
module 7
F11 Seat/CLM
F12 Body control module 3/Body control
module 5
F14 Mirrors/Windows module
F17 Steering wheel controls
F18 VPM/OBS DET Fuses Usage
F19 DLIS
F20 Ventilated seats
F21 NOT R/C
F22 Heated steering wheel
F23 MISC R/C
F24 Instrument panel cluster ignition/
Overhead
F25 Heating, ventilation, and air conditioning
ignition/Heating,
ventilation, and air
conditioning auxiliary
F26 USB ports/Special equipment option
retained accessory
power
F27 Accessory power outlet/retained
accessory power
F28 Accessory power outlet/Battery

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
378 Vehicle Care
FusesUsage
F30 Sensing and diagnostic module/
Parking brake
F31 Body control module 4
F32 Special equipment option/Data link
connection
F33 Body control module 8
F34 Cargo lamp
F40 CGM
F41 Infotainment 1
F42 TCP
F43 –
F44 AVM
F45 Body control module 2
F46 Heating, ventilation, and air conditioning/
Battery 1
F47 Instrument panel cluster/Battery
F48 Transmission control module Fuses
Usage
F49 Body control module 1
F50 –
F51 Battery 1
F52 Battery 2
F53 –
F54 Sunroof
F55 Driver power seat
F56 DC DC TRANS 1
F57 DC DC TRANS 2
F58 Infotainment 2
Circuit
Breakers Usage
1 Accessory power outlet 2
2 Accessory power outlet 1/Cigarette
Lighter
3 Accessory power outlet 3
4 Accessory power outlet 4 Relays
Usage
K1 Run/Crank
K2 Retained accessory power/Accessory 1
K4 Retained accessory power/Accessory 2
K5 –

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
390 Vehicle Care
remain continuously illuminated.
This sequence will continue upon
subsequent vehicle start-ups as
long as the malfunction exists.
When the malfunction indicator is
illuminated, the system may not be
able to detect or signal low tire
pressure as intended. TPMS
malfunctions may occur for a variety
of reasons, including the installation
of replacement or alternate tires or
wheels on the vehicle that prevent
the TPMS from functioning properly.
Always check the TPMS malfunction
telltale after replacing one or more
tires or wheels on your vehicle to
ensure that the replacement or
alternate tires and wheels allow the
TPMS to continue to function
properly.
SeeTire Pressure Monitor
Operation 0390.
See Radio Frequency Statement
0 472.Tire Pressure Monitor
Operation
This vehicle may have a Tire
Pressure Monitor System (TPMS).
The TPMS is designed to warn the
driver when a low tire pressure
condition exists. TPMS sensors are
mounted onto each tire and wheel
assembly, excluding the spare tire
and wheel assembly. The TPMS
sensors monitor the air pressure in
the tires and transmit the tire
pressure readings to a receiver
located in the vehicle.
When a low tire pressure condition
is detected, the TPMS illuminates
the low tire pressure warning light
located on the instrument cluster.
If the warning light comes on, stop
as soon as possible and inflate the
tires to the recommended pressure shown on the Tire and Loading
Information label. See
Vehicle Load
Limits 0200.
A message to check the pressure in
a specific tire displays in the Driver
Information Center (DIC). The low
tire pressure warning light and the
DIC warning message come on at
each ignition cycle until the tires are
inflated to the correct inflation
pressure. If the vehicle has DIC
buttons, tire pressure levels can be
viewed. For additional information
and details about the DIC operation
and displays, see Driver Information
Center (DIC) (Base Level) 0148 or
Driver Information Center (DIC)
(Midlevel and Uplevel) 0149.
The low tire pressure warning light
may come on in cool weather when
the vehicle is first started, and then
turn off as the vehicle is driven. This
could be an early indicator that the
air pressure is getting low and
needs to be inflated to the proper
pressure.
A Tire and Loading Information label
shows the size of the original
equipment tires and the correct

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
428 Vehicle Care
light in the instrument cluster
will stop flashing and stay lit.
SeeFour-Wheel-Drive Light
0 142.
8. Start the engine. Check that the vehicle is in 2
m
(Two-Wheel Drive High) by
starting the engine and shifting
the transmission to D (Drive)
and then to R (Reverse). There
should be movement of the
vehicle while shifting.
9. Shift the transmission to P (Park) and turn off the
ignition.
10. Release the parking brake and remove the wheel blocks.
11. Reset any lost presets. The outside temperature
display will default to 0 °C (32 °
F) but will reset with normal
usage.
Dolly TowingCaution
Do not tow this vehicle with two
wheels on the ground, or vehicle
damage could occur. This
damage would not be covered by
the vehicle warranty.
Dolly towing this vehicle is not
allowed with either the front or the
rear tires on the ground for
two-wheel drive or four-wheel drive,
regardless of transfer case.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
Vehicle Care 435
Original manufacturer replacement
parts will provide the corrosion
protection while maintaining the
vehicle warranty.
Finish Damage
Quickly repair minor chips and
scratches with touch-up materials
available from your dealer to avoid
corrosion. Larger areas of finish
damage can be corrected in your
dealer's body and paint shop.
Chemical Paint Spotting
Airborne pollutants can fall upon
and attack painted vehicle surfaces
causing blotchy, ring-shaped
discolorations, and small, irregular
dark spots etched into the paint
surface. Refer to“Finish Care”
previously in this section.
Interior Care
To prevent dirt particle abrasions,
regularly clean the vehicle's interior.
Immediately remove any soils.
Newspapers or dark garments can
transfer color to the vehicle’s
interior. Use a soft bristle brush to remove
dust from knobs and crevices on the
instrument cluster. Using a mild
soap solution, immediately remove
hand lotions, sunscreen, and insect
repellent from all interior surfaces or
permanent damage may result.
Use cleaners specifically designed
for the surfaces being cleaned to
prevent permanent damage. Apply
cleaners directly to the cleaning
cloth. Do not spray cleaners on any
switches or controls. Remove
cleaners quickly.
Before using cleaners, read and
follow all safety instructions on the
label. While cleaning the interior,
open the doors and windows to get
proper ventilation.
To prevent damage, do not clean
the interior using the following
cleaners or techniques:
.
Never use a razor or any other
sharp object to remove soil from
any interior surface.
. Never use a brush with stiff
bristles. .
Never rub any surface
aggressively or with too much
pressure.
. Do not use laundry detergents or
dishwashing soaps with
degreasers. For liquid cleaners,
use approximately 20 drops per
3.8 L (1 gal) of water.
A concentrated soap solution will
create streaks and attract dirt.
Do not use solutions that contain
strong or caustic soap.
. Do not heavily saturate the
upholstery when cleaning.
. Do not use solvents or cleaners
containing solvents.
Interior Glass
To clean, use a terry cloth fabric
dampened with water. Wipe droplets
left behind with a clean dry cloth.
If necessary, use a commercial
glass cleaner after cleaning with
plain water.