2018 GMC SIERRA brake light

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
368 Vehicle Care
Replacing Brake System Parts
Always replace brake system parts
with new, approved replacement
parts. If this is not done, the brakes
may not work properly. The braking
performance expected can change
in many other ways if the wrong
replacement brake parts are
installed or parts are improperly
installed.
Brake Fluid
The brake master cylinder reservoir
is filled with DOT 3 brake fluid. See
Engine Compartment Overview
0345 for the location of the
reservoir.
There are only two reasons why the
brake fluid level in the reservoir may
go down: .
Normal brake lining wear. When
new linings are installed, the
fluid level goes back up.
. A fluid leak in the brake
hydraulic system. Have the
brake hydraulic system fixed.
With a leak, the brakes will not
work well.
Always clean the brake fluid
reservoir cap and the area around
the cap before removing it.
Do not top off the brake fluid.
Adding fluid does not correct a leak.
If fluid is added when the linings are
worn, there will be too much fluid
when new brake linings are
installed. Add or remove fluid, as
necessary, only when work is done
on the brake hydraulic system.
{Warning
If too much brake fluid is added, it
can spill on the engine and burn,
if the engine is hot enough. You
or others could be burned, and
the vehicle could be damaged. (Continued)
Warning (Continued)
Add brake fluid only when work is
done on the brake hydraulic
system.
When the brake fluid falls to a low
level, the brake warning light comes
on. See Brake System Warning
Light 0152.
Brake fluid absorbs water over time.
Replace brake fluid at the specified
intervals to prevent increased
stopping distance. See Maintenance
Schedule 0448.
Checking Brake Fluid
Check brake fluid by looking at the
brake fluid reservoir. See Engine
Compartment Overview 0345.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
402 Vehicle Care
TPMS sensor. The malfunction
light and the DIC message
should go off after the road tire
is replaced and the sensor
matching process is performed
successfully. See "TPMS Sensor
Matching Process" later in this
section.
. The TPMS sensor matching
process was not done or not
completed successfully after
rotating the tires. The
malfunction light and the DIC
message should go off after
successfully completing the
sensor matching process. See
"TPMS Sensor Matching
Process" later in this section.
. One or more TPMS sensors are
missing or damaged. The
malfunction light and the DIC
message should go off when the
TPMS sensors are installed and
the sensor matching process is
performed successfully. See
your dealer for service.
. Replacement tires or wheels do
not match the original equipment
tires or wheels. Tires and wheels other than those recommended
could prevent the TPMS from
functioning properly. See
Buying
New Tires 0408.
. Operating electronic devices or
being near facilities using radio
wave frequencies similar to the
TPMS could cause the TPMS
sensors to malfunction.
If the TPMS is not functioning
properly, it cannot detect or signal a
low tire pressure condition. See
your dealer for service if the TPMS
malfunction light and DIC message
come on and stay on.
Tire Fill Alert (If Equipped)
This feature provides visual and
audible alerts outside the vehicle to
help when inflating an underinflated
tire to the recommended cold tire
pressure.
When the low tire pressure warning
light comes on: 1. Park the vehicle in a safe, level place.
2. Set the parking brake firmly. 3. Place the vehicle in P (Park).
4. Add air to the tire that is
underinflated. The turn signal
lamp will flash.
When the recommended
pressure is reached, the horn
sounds once and the turn
signal lamp will stop flashing
and briefly turn solid.
Repeat these steps for all
underinflated tires that have
illuminated the low tire pressure
warning light.
If the tire is overinflated by more
than 35 kPa (5 psi), the horn will
sound multiple times and the turn
signal lamp will continue to flash for
eight seconds after filling stops. To
release and correct the pressure,
while the turn signal lamp is still
flashing, briefly press the center of
the valve stem. When the
recommended pressure is reached,
the horn sounds once.
If the turn signal lamp does not flash
within 15 seconds after starting to
inflate the tire, the tire fill alert has
not been activated or is not working.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Vehicle Care 403
If the hazard warning flashers are
on, the tire fill alert visual feedback
will not work properly.
The TPMS will not activate the tire
fill alert properly under the following
conditions:
.There is interference from an
external device or transmitter.
. The air pressure from the
inflation device is not sufficient
to inflate the tire.
. There is a malfunction in
the TPMS.
. There is a malfunction in the
horn or turn signal lamps.
. The identification code of the
TPMS sensor is not registered to
the system.
. The battery of the TPMS sensor
is low.
If the tire fill alert does not operate
due to TPMS interference, move the
vehicle about 1 m (3 ft) back or
forward and try again. If the tire fill
alert feature is not working, use a
tire pressure gauge.TPMS Sensor Matching
Process
Each TPMS sensor has a unique
identification code. The identification
code needs to be matched to a new
tire/wheel position after rotating the
vehicle’s tires or replacing one or
more of the TPMS sensors. Also,
the TPMS sensor matching process
should be performed after replacing
a spare tire with a road tire
containing the TPMS sensor. The
malfunction light and the DIC
message should go off at the next
ignition cycle. The sensors are
matched to the tire/wheel positions,
using a TPMS relearn tool, in the
following order: driver side front tire,
passenger side front tire, passenger
side rear tire, and driver side rear.
See your dealer for service or to
purchase a relearn tool. A TPMS
relearn tool can also be purchased.
See Tire Pressure Monitor
Sensor Activation Tool at
www.gmtoolsandequipment.com or
call 1-800-GM TOOLS
(1-800-468-6657). There are two minutes to match the
first tire/wheel position, and
five minutes overall to match all four
tire/wheel positions. If it takes
longer, the matching process stops
and must be restarted.
The TPMS sensor matching
process is:
1. Set the parking brake.
2. Turn the ignition on without starting the vehicle.
3. Uplevel DIC Only: Make sure the Tire Pressure info page
option is turned on. The info
pages on the DIC can be
turned on and off through the
Settings menu. See Driver
Information Center (DIC)
(Uplevel and Denali Cluster)
0 160 orDriver Information
Center (DIC) (Base Level
Cluster) 0158.
4. If the vehicle has an uplevel DIC, use the DIC controls on
the right side of the steering
wheel to scroll to the Tire
Pressure screen under the DIC
info page.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
408 Vehicle Care
Vehicle Storage
Tires age when stored normally
mounted on a parked vehicle. Park
a vehicle that will be stored for at
least a month in a cool, dry, clean
area away from direct sunlight to
slow aging. This area should be free
of grease, gasoline, or other
substances that can deteriorate
rubber.
Parking for an extended period can
cause flat spots on the tires that
may result in vibrations while
driving. When storing a vehicle for
at least a month, remove the tires or
raise the vehicle to reduce the
weight from the tires.
Buying New Tires
GM has developed and matched
specific tires for the vehicle. The
original equipment tires installed
were designed to meet General
Motors Tire Performance Criteria
Specification (TPC Spec)
system rating. When
replacement tires are needed,GM strongly recommends
buying tires with the same TPC
Spec rating.
GM's exclusive TPC Spec
system considers over a dozen
critical specifications that impact
the overall performance of the
vehicle, including brake system
performance, ride and handling,
traction control, and tire
pressure monitoring
performance. GM's TPC Spec
number is molded onto the tire's
sidewall near the tire size. If the
tires have an all-season tread
design, the TPC Spec number
will be followed by MS for mud
and snow. See
Tire Sidewall
Labeling 0391 for additional
information.
GM recommends replacing worn
tires in complete sets of four (six
for dual rear wheels). Uniform
tread depth on all tires will help
to maintain the performance of
the vehicle. Braking and handling performance may be
adversely affected if all the tires
are not replaced at the same
time. If proper rotation and
maintenance have been done,
all four tires (six for dual rear
wheels) should wear out at
about the same time. See
Tire
Rotation 0405 for information
on proper tire rotation. However,
if it is necessary to replace only
one axle set of worn tires, place
the new tires on the rear axle
(two for single rear wheels, four
for dual rear wheels).
{Warning
Tires could explode during
improper service. Attempting
to mount or dismount a tire
could cause injury or death.
Only your dealer or authorized
tire service center should
mount or dismount the tires.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Vehicle Care 435
5. Use a clamping devicedesigned for towing to ensure
that the front wheels are locked
into the straight position.
6. Turn the ignition off.
Four-Wheel-Drive Vehicles
{Warning
Shifting a four-wheel-drive
vehicle's transfer case into
N (Neutral) can cause the vehicle
to roll even if the transmission is
in P (Park). You or others could
be injured. Set the parking brake
before shifting the transfer case
to N (Neutral). To dolly tow a four-wheel-drive
vehicle from the rear:
1. Drive the rear wheels onto the dolly.
2. Set the parking brake. See Parking Brake 0281.
3. Put the transmission in P (Park).
4. Secure the vehicle to the dolly following the manufacturer's
instructions.
5. Use a clamping device designed for towing to ensure
that the front wheels are locked
into the straight position.
6. Shift the transfer case to N (Neutral). See “Shifting into
N (Neutral)” underFour-Wheel
Drive 0272 for the proper
procedure.
7. Turn the ignition off.
Appearance Care
Exterior Care
Locks
Locks are lubricated at the factory.
Use a de-icing agent only when
absolutely necessary, and have the
locks greased after using. See
Recommended Fluids and
Lubricants 0456.
Washing the Vehicle
To preserve the vehicle's finish,
wash it often and out of direct
sunlight.
{Warning
Do not power wash any part of
the vehicle’s interior, including the
vinyl floor covering. This could
damage safety and other systems
in the vehicle, which would not be
covered by the vehicle warranty.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
454 Service and Maintenance
Battery
The 12-volt battery supplies power
to start the engine and operate any
additional electrical accessories.
.To avoid break-down or failure to
start the vehicle, maintain a
battery with full cranking power.
. Trained dealer technicians have
the diagnostic equipment to test
the battery and ensure that the
connections and cables are
corrosion-free.
Belts
. Belts may need replacing if they
squeak or show signs of
cracking or splitting.
. Trained dealer technicians have
access to tools and equipment
to inspect the belts and
recommend adjustment or
replacement when necessary. Brakes
Brakes stop the vehicle and are
crucial to safe driving.
.
Signs of brake wear may include
chirping, grinding, or squealing
noises, or difficulty stopping.
. Trained dealer technicians have
access to tools and equipment
to inspect the brakes and
recommend quality parts
engineered for the vehicle.
Fluids
Proper fluid levels and approved
fluids protect the vehicle’s systems
and components. See
Recommended Fluids and
Lubricants 0456 for GM approved
fluids.
. Engine oil and windshield
washer fluid levels should be
checked at every fuel fill.
. Instrument cluster lights may
come on to indicate that fluids
may be low and need to be
filled. Hoses
Hoses transport fluids and should
be regularly inspected to ensure
that there are no cracks or leaks.
With a multi-point inspection, your
dealer can inspect the hoses and
advise if replacement is needed.
Lamps
Properly working headlamps,
taillamps, and brake lamps are
important to see and be seen on
the road.
.
Signs that the headlamps need
attention include dimming, failure
to light, cracking, or damage.
The brake lamps need to be
checked periodically to ensure
that they light when braking.
. With a multi-point inspection,
your dealer can check the lamps
and note any concerns.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Index 491
IndexA
Accessories andModifications . . . . . . . . . . . . . . . . . . 343
Accessory Power . . . . . . . . . . . . . . . 260
Active Fuel Management . . . . . . . 264
Add-On Electrical Equipment . . . 336
Adding a Snow Plow or Similar Equipment . . . . . . . . . . . . . 337
Additional Information OnStar . . . . . . . . . . . . . . . . . . . . . . . 485
Additional Maintenance and Care . . . . . . . . . . . . . . . . . . . . . . 453
Adjustable Throttle and Brake Pedal . . . . . . . . . . . . . . . . . . . 256
Adjustments Lumbar, Front Seats . . . . . . . . . . . . 60
Agreements Trademarks and License . . . . . 218
Air Cleaner/Filter, Engine . . . . . . . 358
Air Conditioning . . . . . .224, 226, 228
Air Filter, Passenger
Compartment . . . . . . . . . . . . . . . . . 232
Air Vents . . . . . . . . . . . . . . . . . . . . . . . 231
Airbag System Check . . . . . . . . . . . . . . . . . . . . . . . . . . 91
How Does an AirbagRestrain? . . . . . . . . . . . . . . . . . . . . . 82
Passenger Sensing System . . . . 86 Airbag System (cont'd)
What Makes an Airbag
Inflate? . . . . . . . . . . . . . . . . . . . . . . . . 82
What Will You See after an
Airbag Inflates? . . . . . . . . . . . . . . . 82
When Should an Airbag Inflate? . . . . . . . . . . . . . . . . . . . . . . . . 80
Where Are the Airbags? . . . . . . . . 78
Airbags
Adding Equipment to theVehicle . . . . . . . . . . . . . . . . . . . . . . . . 90
Light On-Off . . . . . . . . . . . . . . . . . . 147
On-Off Light . . . . . . . . . . . . . . . . . . 147
On-Off Switch . . . . . . . . . . . . . . . . . . 84
Passenger Status Indicator . . . 149
Readiness Light . . . . . . . . . . . . . . 147
Servicing Airbag-Equipped Vehicles . . . . . . . . . . . . . . . . . . . . . . . 90
System Check . . . . . . . . . . . . . . . . . . 77
Alarm Vehicle Security . . . . . . . . . . . . . . . . 44
All-Season Tires . . . . . . . . . . . . . . . . 389
All-Terrain Tires . . . . . . . . . . . . . . . . . 391
AM-FM Radio . . . . . . . . . . . . . . . . . . . 190
Antenna Fixed Mast . . . . . . . . . . . . . . . . . . . 194
Multi-band . . . . . . . . . . . . . . . . . . . . 194
Antilock Brake System (ABS) . . . 280

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
492 Index
Antilock Brake System(ABS) (cont'd)
Warning Light . . . . . . . . . . . . . . . . . 152
Appearance Care
Exterior . . . . . . . . . . . . . . . . . . . . . . . 435
Interior . . . . . . . . . . . . . . . . . . . . . . . . 441
Apple CarPlay and Android Auto . . . . . . . . . . . . . . . . . . 217
Assistance Program,
Roadside . . . . . . . . . . . . . . . . . . . . . . 469
Assistance Systems for Driving . . . . . . . . . . . . . . . . . . . . . . . . 292
Assistance Systems for
Parking and Backing . . . . . . . . . . 289
Audio Bluetooth . . . . . . . . . . . . . . . . . . . . . 204
Theft-Deterrent Feature . . . . . . . 187
Audio Players
CD . . . . . . . . . . . . . . . . . . . . . . . . . . . 195
Automatic Dimming Mirrors . . . . . . . . . . . . . . . . 50
Door Locks . . . . . . . . . . . . . . . . . . . . . 41
Forward Braking . . . . . . . . . . . . . . 294
Headlamp System . . . . . . . . . . . . 179
Transmission . . . . . . . . . . . . . . . . . 265
Transmission Fluid . . . . . . 354, 357
Automatic Transmission
Manual Mode . . . . . . . . . . . . . . . . . 268 Automatic Transmission (cont'd)
Shift Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 374
Auxiliary
Roof Mounted Lamp . . . . . . . . . . 182
Auxiliary Jack . . . . . . . . . . . . . . . . . . . 203
Avoiding Untrusted Media Devices . . . . . . . . . . . . . . . . . . . . . . . 195
Axle, Front . . . . . . . . . . . . . . . . . . . . . . 370
Axle, Rear . . . . . . . . . . . . . . . . . . . . . . 371
B
Battery Exterior Lighting Battery
Saver . . . . . . . . . . . . . . . . . . . . . . . 185
Load Management . . . . . . . . . . . . 184
Power Protection . . . . . . . . . . . . . 185
Battery - North America . . . . 369, 426
Blade Replacement, Wiper . . . . . 375
Blind Spot Mirrors . . . . . . . . . . . . . . . 50
Bluetooth Overview . . . . . . . . . . . . . . . . 211, 213
Bluetooth Audio . . . . . . . . . . . . . . . . 204
Brake Pedal and AdjustableThrottle . . . . . . . . . . . . . . . . . . . . . . 256
System Warning Light . . . . . . . . 152
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . 367 Brakes (cont'd)
Antilock . . . . . . . . . . . . . . . . . . . . . . . 280
Assist . . . . . . . . . . . . . . . . . . . . . . . . . 281
Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 368
Parking . . . . . . . . . . . . . . . . . . . . . . . 281
Braking . . . . . . . . . . . . . . . . . . . . . . . . . 236 Automatic Forward . . . . . . . . . . . 294
Break-In, New Vehicle . . . . . . . . . . 255
Bulb Replacement Center High-MountedStoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . . . 380
Halogen Bulbs . . . . . . . . . . . . . . . . 378
Headlamp Aiming . . . . . . . . . . . . . 377
Headlamps . . . . . . . . . . . . . . . . . . . 378
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . 378
Taillamps, Turn Signal,
Stoplamps, and Back-up
Lamps . . . . . . . . . . . . . . . . . . . . . . 378
Buying New Tires . . . . . . . . . . . . . . . 408
C
Calibration . . . . . . . . . . . . . . . . . . . . . . 131
California Fuel Requirements . . . . . . . . . . . 300