2021 GMC ACADIA warning light

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Driving and Operating 253
Ais green if LKA is ready to assist. LKA
may assist by gently turning the steering
wheel if the vehicle approaches a detected
lane marking.
Ais amber when
assisting. It may also provide a Lane
Departure Warning (LDW) alert by flashing
Aamber if the vehicle crosses a
detected lane marking. Additionally, there
may be three beeps on the right or left,
depending on the lane departure direction.
Take Steering
The LKA system does not continuously steer
the vehicle. If LKA does not detect active
driver steering, an alert and chime may be
provided. Steer the vehicle to dismiss. LKA
may become temporarily unavailable after
repeated take steering alerts.
When the System Does Not Seem to
Work Properly
The system performance may be
affected by:
.Close vehicles ahead.
.Sudden lighting changes, such as when
driving through tunnels.
.Banked roads.
.Roads with poor lane markings, such as
two-lane roads. If the LKA system is not functioning
properly when lane markings are clearly
visible, cleaning the windshield may help.
A camera blocked message may display if
the camera is blocked. Some driver
assistance systems may have reduced
performance or not work at all. An LKA or
LDW unavailable message may display if the
systems are temporarily unavailable. This
message could be due to a blocked camera.
The LKA system does not need service. Clean
the outside of the windshield behind the
rearview mirror.
LKA assistance and/or LDW alerts may occur
due to tar marks, shadows, cracks in the
road, temporary or construction lane
markings, or other road imperfections. This
is normal system operation; the vehicle does
not need service. Turn LKA off if these
conditions continue.
Fuel
Top Tier Fuel
GM recommends the use of TOP TIER
Detergent Gasoline to keep the engine clean,
reduce engine deposits, and maintain
optimal vehicle performance. Look for the
TOP TIER Logo or see www.toptiergas.com
for a list of TOP TIER Detergent Gasoline
marketers and applicable countries.
Recommended Fuel
Use regular unleaded gasoline meeting
ASTM specification D4814 with a posted
octane rating of 87
—(R+M)/2 —or higher.
Do not use gasoline with a posted octane
rating of less than 87, as this may cause
engine knock and will lower fuel economy.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Driving and Operating 265
Turn Signals When Towing a Trailer
When properly connected, the trailer turn
signals should 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, seeDriver Mode Control 0228.
Tow/Haul assists when pulling a heavy
trailer or a large or heavy load. See Tow/
Haul Mode 0224.
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 “Weight of the Trailer” under
Trailer Towing 0259.
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 and reduced fuel economy.
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 vehicle
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
226.
{Warning
Trailer 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 0262 for trailer
ratings and hitch setup recommendations.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
266 Driving and Operating
Trailer Tires
Special Trailer (ST) tires differ from vehicle
tires. Trailer tires are designed with stiff
sidewalls to help prevent sway and to
support heavy loads. These features can
make it difficult to determine if the trailer
tire pressures are low only based on a visual
inspection.
Always check all trailer tire pressures before
each trip when the tires are cool. Low trailer
tire pressure is a leading cause of trailer tire
blow-outs.
Trailer tires deteriorate over time. The trailer
tire sidewall will show the week and year
the tire was manufactured. Many trailer tire
manufacturers recommend replacing tires
more than six years old.
Overloading is another leading cause of
trailer tire blow-outs. Never load your trailer
with more weight than the tires are
designed to support. The load rating is
located on the trailer tire sidewall.
Always know the maximum speed rating for
the trailer tires before driving. This may be
significantly lower than the vehicle tire
speed rating. The speed rating may be onthe trailer tire sidewall. If the speed rating is
not shown, the default trailer tire speed
rating is 105 km/h (65 mph).
Conversions and Add-Ons
Add-On Electrical Equipment
{Warning
The Data Link Connector (DLC) is used for
vehicle service and Emission Inspection/
Maintenance testing. See
Malfunction
Indicator Lamp (Check Engine Light) 0107
. 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.
Caution
Some 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 063 and
Adding Equipment to the Airbag-Equipped
Vehicle 063.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Vehicle Care 267
Vehicle Care
General Information
General Information . . . . . . . . . . . . . . . . . . . 268
California Proposition 65 Warning . . . . . 268
California Perchlorate MaterialsRequirements . . . . . . . . . . . . . . . . . . . . . . . 268
Accessories and Modifications . . . . . . . . . 268
Vehicle Checks
Doing Your Own Service Work . . . . . . . . 269
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270
Engine Compartment Overview . . . . . . . . 271
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276
Engine Oil Life System . . . . . . . . . . . . . . . . 278
Automatic Transmission Fluid . . . . . . . . . 279
Engine Air Filter Life System . . . . . . . . . . 279
Engine Air Cleaner/Filter . . . . . . . . . . . . . . 279
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . 281
Engine Overheating . . . . . . . . . . . . . . . . . . . 285
Washer Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 286
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287
Battery - North America . . . . . . . . . . . . . . . 288
All-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . . 289
Park Brake and P (Park) Mechanism Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289
Wiper Blade Replacement . . . . . . . . . . . . . 290
Windshield Replacement . . . . . . . . . . . . . . 290
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 291
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . . . . . . . 292
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . 292
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . 292
LED Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . 292
Electrical System
Electrical System Overload . . . . . . . . . . . . 292
Fuses and Circuit Breakers . . . . . . . . . . . . . 293
Engine Compartment Fuse Block . . . . . . 293
Instrument Panel Fuse Block . . . . . . . . . . 296
Rear Compartment Fuse Block . . . . . . . . . 298
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . . 301
Winter Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . 301
Summer Tires . . . . . . . . . . . . . . . . . . . . . . . . . 302
All-Terrain Tires . . . . . . . . . . . . . . . . . . . . . . . 302
Tire Sidewall Labeling . . . . . . . . . . . . . . . . . 302
Tire Designations . . . . . . . . . . . . . . . . . . . . . . 304
Tire Terminology and Definitions . . . . . 304
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . 307
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 308
Tire Pressure Monitor System . . . . . . . . . 309
Tire Pressure Monitor Operation . . . . . . . 310
Tire Inspection . . . . . . . . . . . . . . . . . . . . . . . . . 313
Tire Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . 313 When It Is Time for New Tires . . . . . . . . . 314
Buying New Tires . . . . . . . . . . . . . . . . . . . . . . 315
Different Size Tires and Wheels . . . . . . . . 316
Uniform Tire Quality Grading . . . . . . . . . . 316
Wheel Alignment and Tire Balance . . . . 318
Wheel Replacement . . . . . . . . . . . . . . . . . . . 318
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . 318
If a Tire Goes Flat . . . . . . . . . . . . . . . . . . . . . 319
Tire Sealant and Compressor Kit . . . . . . 320
Storing the Tire Sealant and
Compressor Kit . . . . . . . . . . . . . . . . . . . . . . 326
Tire Changing . . . . . . . . . . . . . . . . . . . . . . . . . 326
Compact Spare Tire . . . . . . . . . . . . . . . . . . . . 331
Jump Starting
Jump Starting - North America . . . . . . . . 332
Towing the Vehicle
Towing the Vehicle . . . . . . . . . . . . . . . . . . . . 334
Recreational Vehicle Towing . . . . . . . . . . . 335
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 337
Interior Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 341
Floor Mats . . . . . . . . . . . . . . . . . . . . . . . . . . . . 343

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
288 Vehicle Care
Checking Brake Fluid
With the vehicle in P (Park) on a level
surface, the brake fluid level should be
between the minimum and maximum marks
on the brake fluid 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. 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 0108.
Brake fluid absorbs water over time which
degrades the effectiveness of the brake fluid.
Replace brake fluid at the specified intervals
to prevent increased stopping distance. See
Maintenance Schedule 0346.
What to Add
Use only GM approved DOT 3 brake fluid
from a clean, sealed container. See
Recommended Fluids and Lubricants 0354.
{Warning
The wrong or contaminated brake fluid
could result in damage to the brake
system. This could result in the loss of
(Continued)
Warning (Continued)
braking leading to a possible injury.
Always use the proper GM approved
brake fluid.
Caution
If brake fluid is spilled on the vehicle's
painted surfaces, the paint finish can be
damaged. Immediately wash off any
painted surface.
Battery - North America
The original equipment battery is
maintenance free. Do not remove the cap
and do not add fluid.
Refer to the replacement number on the
original battery label when a new battery is
needed. For replacement of the battery, see
your dealer.
Stop/Start System
The vehicle has a Stop/Start system to shut
off the engine to help conserve fuel. See
Stop/Start System0215.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
292 Vehicle Care
Headlamp Aiming
Front Headlamp Aiming
Headlamp aim has been preset and should
need no further adjustment.
If the vehicle is damaged in a crash, the
headlamp aim may be affected.
If adjustment to the headlamps is necessary,
see your dealer.
Bulb Replacement
For the proper type of replacement bulbs,
or any bulb changing procedure not listed in
this section, contact your dealer.
Caution
Do not replace incandescent bulbs with
aftermarket LED replacement bulbs. This
can cause damage to the vehicle electrical
system.
Halogen Bulbs
{Warning
Halogen bulbs have pressurized gas inside
and can burst if you drop or scratch the
bulb. You or others could be injured. Be
sure to read and follow the instructions
on the bulb package.
LED Lighting
This vehicle has several LED lamps. For
replacement of any LED lighting assembly,
contact your dealer.
Electrical System
Electrical System Overload
The vehicle has fuses and circuit breakers to
protect against an electrical system
overload.
When the current electrical load is too
heavy, the circuit breaker opens and closes,
protecting the circuit until the current load
returns to normal or the problem is fixed.
This greatly reduces the chance of circuit
overload and fire caused by electrical
problems.Fuses and circuit breakers protect power
devices in the vehicle.
Replace a bad fuse with a new one of the
identical size and rating.
If there is a problem on the road and a fuse
needs to be replaced, the same amperage
fuse can be borrowed. Choose some feature
of the vehicle that is not needed to use and
replace it as soon as possible.
Headlamp Wiring
An electrical overload may cause the lamps
to go on and off, or in some cases to
remain off. Have the headlamp wiring
checked right away if the lamps go on and
off or remain off.
Windshield Wipers
If the wiper motor overheats due to heavy
snow or ice, the windshield wipers will stop
until the motor cools and will then restart.
Although the circuit is protected from
electrical overload, overload due to heavy
snow or ice may cause wiper linkage
damage. Always clear ice and heavy snow
from the windshield before using the
windshield wipers.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
310 Vehicle Care
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 0310.
See Radio Frequency Statement 0371.
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
0 209.
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. Using the DIC, tire pressure levels can be viewed. For additional
information and details about the DIC
operation and displays see
Driver
Information Center (DIC) (Base) 0115 or
Driver Information Center (DIC) (Midlevel and
Uplevel) 0117.
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,
attached to your vehicle, shows the size of
the original equipment tires and the correct
inflation pressure for the tires when they
are cold. See Vehicle Load Limits 0209, for
an example of the Tire and Loading
Information label and its location. Also see
Tire Pressure 0307.
The TPMS can warn about a low tire
pressure condition but it does not replace
normal tire maintenance. See Tire Inspection
0 313, Tire Rotation 0313 and
Tires 0300.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Vehicle Care 311
Caution
Tire sealant materials are not all the
same. A non-approved tire sealant could
damage the TPMS sensors. TPMS sensor
damage caused by using an incorrect tire
sealant is not covered by the vehicle
warranty. Always use only the GM
approved tire sealant available through
your dealer or included in the vehicle.
Factory-installed Tire Inflator Kits use a
GM-approved liquid tire sealant. Using
non-approved tire sealants could damage the
TPMS sensors. See Tire Sealant and
Compressor Kit 0320 for information
regarding the inflator kit materials and
instructions.
TPMS Malfunction Light and Message
The TPMS will not function properly if one
or more of the TPMS sensors are missing or
inoperable. When the system detects a
malfunction, the low tire pressure warning
light flashes for about one minute and then
stays on for the remainder of the ignition
cycle. A DIC warning message also displays.
The malfunction light and DIC warning
message come on at each ignition cycle until the problem is corrected. Some of the
conditions that can cause these to come
on are:
.One of the road tires has been replaced
with the spare tire. The spare tire does
not have a TPMS sensor. The malfunction
light and 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 0315.
.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.