2019 GMC SIERRA DENALI check engine light

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/15/18
Instruments and Controls 157
Engine Oil Pressure Light
(Uplevel Cluster) CautionLack of proper engine oil
maintenance can damage the
engine. Driving with the engine oil
low can also damage the engine.
The repairs would not be covered
by the vehicle warranty. Check
the oil level as soon as possible.
Add oil if required, but if the oil
level is within the operating range
and the oil pressure is still low,
have the vehicle serviced. Always
follow the maintenance schedule
for changing engine oil. This light should come on briefly as
the engine is started. If it does not
come on, have the vehicle serviced
by your dealer.
If the light comes on and stays on, it
means that oil is not flowing through
the engine properly. The vehicle
could be low on oil and might have
some other system problem. See
your dealer.
Low Fuel Warning Light
This light is near the fuel gauge and
comes on briefly when the ignition is
turned on as a check to show it is
working.
It also comes on when the fuel tank
is low on fuel. The light turns off
when fuel is added. If it does not,
have the vehicle serviced. Security Light The security light should come on
briefly as the engine is started. If it
does not come on, have the vehicle
serviced by your dealer. If the
system is working normally, the
indicator light turns off.
If the light stays on and the engine
does not start, there could be a
problem with the theft-deterrent
system. See Immobilizer Operation
0 55 .
High-Beam On Light

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
Driving and Operating 205CautionDo 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 0 415 .
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. { WarningWet 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.
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

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
Driving and Operating 241ABS is active, it may indicate that
road surfaces are slippery. Braking
sooner may be required for driving
conditions.
Braking in Emergencies ABS allows you to steer and brake
at the same time. In many
emergencies, steering can help
more than even the very best
braking.
Electric Parking Brake
The vehicle has an Electric Parking
Brake (EPB). The EPB can always
be activated, even if the ignition is off. To prevent draining the battery,
avoid repeated cycles of the EPB
when the engine is not running.
The system has a
Y or PARK
Electric Parking Brake light, and a
8Service Parking Brake light.
See Electric Parking Brake Light
0 152 and Service Electric Parking
Brake Light 0 152 . There are also
parking brake-related Driver
Information Center (DIC) messages.
Before leaving the vehicle, check for
the
Y or PARK light to ensure that
the parking brake is applied.
EPB Apply To apply the EPB:
1. Be sure the vehicle is at a
complete stop.
2. Press the EPB switch
momentarily.
The
Y or PARK light will flash and
then stay on once the EPB is fully
applied. If the
Y or PARK light
flashes continuously, then the EPB
is only partially applied or there is a problem with the EPB. A DIC
message will display. Release the
EPB and try to apply it again. If the
light does not come on, or keeps
flashing, have the vehicle serviced.
Do not drive the vehicle if the
Y or
PARK light is flashing. See your
dealer. See Electric Parking Brake
Light 0 152 .
If the
8 light is on, press the EPB
switch and hold it. Continue to hold
the switch until the
Y or PARK
light remains on. If the
8 light
remains on, see your dealer.
If the EPB is applied while the
vehicle is moving, the vehicle will
decelerate as long as the switch is
pressed. If the switch is pressed
until the vehicle comes to a stop,
the EPB will remain applied.
The vehicle may automatically apply
the EPB in some situations when
the vehicle is not moving. This is
normal, and is done to periodically
check the correct operation of the
EPB system.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
Driving and Operating 289Electric Brake Control Wiring
Provisions If the vehicle is not equipped with
an integrated trailer brake controller,
and the trailer has electric brakes, a
trailer brake controller needs to be
installed on the vehicle. The brake
controller should be installed by
your dealer or a qualified service
center.
If equipped, there is a trailer brake
jumper harness provided with the
vehicle. The connector on the trailer
brake jumper harness is attached to
a mating connector to the left of the
steering wheel behind the knee
bolster. The four blunt cut wires on
the jumper harness need to be
connected to an aftermarket electric
trailer brake controller. The harness
contains the following circuits:
Electric Trailer
Brakes Blue
Battery Feed Red/Violet or
Red/Black
Brake Apply
Signal White/Blue Ground Black
The fuse for the electric trailer brake
circuit is in the engine compartment
fuse block, but the wires may not be
connected. They should be
connected by your dealer or a
qualified service center.
Refer to the aftermarket electric
trailer brake controller owner's
manual to determine wire color
coding of the electric trailer brake
controller. The wire colors on the
brake controller may be different
from the vehicle.
Trailer Lamps Always check all trailer lamps are
working at the beginning of each
trip, and periodically on longer trips.
If equipped, the trailering app will
monitor the brake lamps, turn signal
lamps, running lamps and reverse
lamps on the trailer. DIC messages
may be displayed if lighting circuit
issues are detected on the trailer. The trailer bulbs can be observed
by starting the trailer light test
sequence. See Trailering App
0 296 .
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 0 246 .
Tow/Haul assists when pulling a
heavy trailer or a large or heavy
load. See Tow/Haul Mode 0 234 .
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

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
294 Driving and Operating brakes 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 slow the vehicle. TSC will not
function if StabiliTrak/ESC is turned
off. See Traction Control/Electronic
Stability Control 0 243 .
{ WarningTrailer sway can result in a crash
and in serious injury or death,
even if the vehicle is equipped
with TSC.
If the trailer begins to sway,
reduce vehicle speed by
gradually removing your foot from
the accelerator. Then pull over to
check the trailer and vehicle to
help correct possible causes,
including an improperly or
overloaded trailer, unrestrained
cargo, improper trailer hitch
configuration, or improperly
inflated or incorrect vehicle or
trailer tires. See Towing
Equipment 0 285 for trailer ratings
and hitch setup
recommendations. Aftermarket Electronic Trailer
Sway Control Devices Some trailers may come equipped
with an electronic device designed
to reduce or control trailer sway.
Aftermarket equipment
manufacturers also offer similar
devices that connect to the wiring
between the trailer and the vehicle.
These devices may interfere with
the vehicle ’ s trailer brake or other
systems, including integrated
anti-sway systems, if equipped.
Messages related to trailer
connections or trailer brakes could
appear on the DIC. The effects of
these aftermarket devices may have
on vehicle handling or trailer brake
performance is not known.
{ Warning
Use of aftermarket electronic
trailer sway control devices could
result in reduced trailer brake
performance, loss of trailer
brakes, or other malfunctions, and
(Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
306 Driving and Operating If Tow/Haul Mode is off and this
setting is on for a Trailer Profile,
each time the ignition is turned on a
reminder will appear to turn on Tow/
Haul Mode when the Trailer Profile
is active.
If Tow/Haul Mode is on and this
setting is on for a Trailer Profile, the
reminder will not appear when the
Trailer Profile is active.
Conversions and
Add-Ons Add-On Electrical
Equipment
{ WarningThe Data Link Connector
(DLC) is used for vehicle service
and Emission Inspection/
Maintenance testing. See
Malfunction Indicator Lamp
(Check Engine Light) 0 149 .
A device connected to the DLC —
such as an aftermarket fleet or
driver-behavior tracking device —
may interfere with vehicle
systems. This could affect vehicle
operation and cause a crash.
Such devices may also access
information stored in the vehicle ’ s
systems. CautionSome electrical equipment can
damage the vehicle or cause
components to not work and
would not be covered by the
vehicle warranty. Always check
with your dealer before adding
electrical equipment.
Add-on equipment can drain the
vehicle's 12-volt battery, even if the
vehicle is not operating.
The vehicle has an airbag system.
Before attempting to add anything
electrical to the vehicle, see
Servicing the Airbag-Equipped
Vehicle 0 96 and Adding Equipment
to the Airbag-Equipped Vehicle
0 97 .
For information on wiring auxiliary
switches, see www.gmupfitter.com
or contact your dealer.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/15/18
Vehicle Care 311
Vehicle Care General Information General Information . . . . . . . . . . 312
California Proposition
65 Warning . . . . . . . . . . . . . . . . . 313
California Perchlorate
Materials Requirements . . . . . 313
Accessories and
Modifications . . . . . . . . . . . . . . . . 313
Vehicle Checks Doing Your Own
Service Work . . . . . . . . . . . . . . . 314
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 314
Engine Compartment
Overview . . . . . . . . . . . . . . . . . . . . 316
Engine Oil . . . . . . . . . . . . . . . . . . . . 321
Engine Oil Life System . . . . . . . 323
Automatic Transmission
Fluid . . . . . . . . . . . . . . . . . . . . . . . . 325
Engine Air Filter Life
System . . . . . . . . . . . . . . . . . . . . . . 325
Engine Air Cleaner/Filter . . . . . . 326
Cooling System . . . . . . . . . . . . . . 327
Engine Overheating . . . . . . . . . . 331
Overheated Engine Protection
Operating Mode . . . . . . . . . . . . . 333
Engine Fan . . . . . . . . . . . . . . . . . . . 333 Washer Fluid . . . . . . . . . . . . . . . . . 334
Brakes . . . . . . . . . . . . . . . . . . . . . . . 335
Brake Pad Life System . . . . . . . 335
Brake Fluid . . . . . . . . . . . . . . . . . . . 336
Battery - North America . . . . . . 337
Four-Wheel Drive . . . . . . . . . . . . . 340
Front Axle . . . . . . . . . . . . . . . . . . . . 340
Rear Axle . . . . . . . . . . . . . . . . . . . . 341
Noise Control System . . . . . . . . 342
Starter Switch Check . . . . . . . . . 343
Ignition Transmission Lock
Check . . . . . . . . . . . . . . . . . . . . . . . 343
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . 343
Wiper Blade Replacement . . . . 344
Windshield Replacement . . . . . 345
Gas Strut(s) . . . . . . . . . . . . . . . . . . 345
Headlamp Aiming Headlamp Aiming . . . . . . . . . . . . 346
Bulb Replacement Bulb Replacement . . . . . . . . . . . . 346
Halogen Bulbs . . . . . . . . . . . . . . . . 346
LED Lighting . . . . . . . . . . . . . . . . . 347
Headlamps, Front Turn Signal,
Sidemarker, and Parking
Lamps . . . . . . . . . . . . . . . . . . . . . . 347
Taillamps, Turn Signal,
Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 347 Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . . . 348
License Plate Lamp . . . . . . . . . . 349
Electrical System Electrical System Overload . . . 349
Fuses and Circuit Breakers . . . 350
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 350
Instrument Panel Fuse Block
(Right) . . . . . . . . . . . . . . . . . . . . . . 354
Instrument Panel Fuse
Block (Left) . . . . . . . . . . . . . . . . . 356
Wheels and Tires Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 358
All-Season Tires . . . . . . . . . . . . . . 359
Winter Tires . . . . . . . . . . . . . . . . . . 359
Low-Profile Tires . . . . . . . . . . . . . 360
All-Terrain Tires . . . . . . . . . . . . . . . 360
Tire Sidewall Labeling . . . . . . . . 360
Tire Designations . . . . . . . . . . . . . 363
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . 364
Tire Pressure . . . . . . . . . . . . . . . . . 367
Tire Pressure for High-Speed
Operation . . . . . . . . . . . . . . . . . . . 368
Tire Pressure Monitor
System . . . . . . . . . . . . . . . . . . . . . . 369

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/15/18
Vehicle Care 3974. Turn the ignition off on both
vehicles. Unplug unnecessary
accessories plugged into the
accessory power outlets. Turn
off the radio and all the lamps
that are not needed. This will
avoid sparks and help save
both batteries. And it could
save the radio!
5. Open the hood on the other
vehicle and locate the
positive (+) and negative ( − )
terminal locations on that
vehicle.
The positive (+) terminal is
under a red plastic cover at the
positive battery post. To
uncover the positive (+)
terminal, open the red plastic
cover.
For more information on the
location of the remote
positive (+) and remote
negative ( − ) terminals, see
Engine Compartment Overview
0 316 . { WarningAn electric fan can start up even
when the engine is not running
and can injure you. Keep hands,
clothing, and tools away from any
underhood electric fan.
{ WarningUsing a match near a battery can
cause battery gas to explode.
People have been hurt doing this,
and some have been blinded.
Use a flashlight if you need more
light.
Battery fluid contains acid that
can burn you. Do not get it on
you. If you accidentally get it in
your eyes or on your skin, flush
the place with water and get
medical help immediately. { WarningFans or other moving engine
parts can injure you badly. Keep
your hands away from moving
parts once the engine is running.
6. Check that the jumper cables
do not have loose or missing
insulation. If they do, you could
get a shock. The vehicles
could be damaged too.
Before you connect the cables,
here are some basic things you
should know. Positive (+) will
go to positive (+) or to a remote
positive (+) terminal if the
vehicle has one. Negative ( − )
will go to a heavy, unpainted
metal engine part or to a
remote negative ( − ) terminal if
the vehicle has one.
Do not connect positive (+) to
negative ( − ) or you will get a
short that would damage the
battery and maybe other parts
too. And do not connect the
negative ( − ) cable to the