check engine GMC ACADIA 2018 User Guide

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Instruments and Controls 143
Engine Oil Pressure Light
Oil pressure can vary with engine
speed, outside temperature, and oil
viscosity.
On some models, the oil pump will
vary engine oil pressure according
to engine needs. Oil pressure may
change quickly as the engine speed
or load varies. This is normal. If the
oil pressure warning light or Driver
Information Center (DIC) message
indicates oil pressure outside the
normal operating range, check the
vehicle's oil as soon as possible.
Caution
Lack 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,(Continued)
Caution (Continued)
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
(Base Level)
Metric Shown, English Similar
This light comes on for a few
seconds when the ignition is turned
on as a check to indicate it is
working. If it does not come on,
have it fixed.
The low fuel warning light comes on
and a chime sounds when the
vehicle is low on fuel. The light turns
off when fuel is added to the
fuel tank.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
144 Instruments and Controls
Low Fuel Warning Light
(Midlevel and Uplevel)
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. SeeImmobilizer Operation
0 48.
High-Beam On Light
This light comes on when the
high-beam headlamps are in use.
See Headlamp High/Low-Beam
Changer 0166.
IntelliBeam Light
This light comes on when the
IntelliBeam system, if equipped, is
enabled. See Exterior Lamp
Controls 0164.
Front Fog Lamp Light
The fog lamp light comes on when
the fog lamps are in use.
The light goes out when the fog
lamps are turned off. See Fog
Lamps 0168 for more information.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
210 Driving and Operating
Before Driving Off-Road
.Have all necessary maintenance
and service work completed.
. Fuel the vehicle, fill fluid levels,
and check inflation pressure in
all tires, including the spare,
if equipped.
. Read all the information about
all-wheel-drive vehicles in this
manual.
. Make sure all underbody
shields, if equipped, are properly
attached.
. Know the local laws that apply to
off-road driving.
To gain more ground clearance if
needed, it may be necessary to
remove the front fascia lower air
dam. However, driving without the
air dam reduces fuel economy.Caution
Operating the vehicle for
extended periods without the front
fascia lower air dam installed can
cause improper airflow to the
engine. Reattach the front fascia
air dam after off-road driving.
Loading the Vehicle for
Off-Road Driving
{Warning
. Unsecured cargo on the
load floor can be tossed
about when driving over
rough terrain. You or your
passengers can be struck
by flying objects. Secure the
cargo properly.
. Keep cargo in the cargo
area as far forward and as
low as possible. The
(Continued)
Warning (Continued)
heaviest things should be
on the floor, forward of the
rear axle.
. Heavy loads on the roof
raise the vehicle's center of
gravity, making it more likely
to roll over. You can be
seriously or fatally injured if
the vehicle rolls over. Put
heavy loads inside the
cargo area, not on the roof.
For more information about loading
the vehicle, see Vehicle Load Limits
0 217.
Environmental Concerns
.
Always use established trails,
roads, and areas that have been
set aside for public off-road
recreational driving and obey all
posted regulations.
. Do not damage shrubs, flowers,
trees, or grasses or disturb
wildlife.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Driving and Operating 215
Hill and Mountain Roads
Driving on steep hills or through
mountains is different than driving
on flat or rolling terrain. Tips include:
.Keep the vehicle serviced and in
good shape.
. Check all fluid levels and brakes,
tires, cooling system, and
transmission.
. Shift to a lower gear when going
down steep or long hills.
{Warning
Using the brakes to slow the
vehicle on a long downhill slope
can cause brake overheating, can
reduce brake performance, and
could result in a loss of braking.
Shift the transmission to a lower
gear to let the engine assist the
brakes on a steep downhill slope.
{Warning
Coasting downhill in N (Neutral)
or with the ignition off is
dangerous. This can cause
overheating of the brakes and
loss of steering assist. Always
have the engine running and the
vehicle in gear.
. Drive at speeds that keep the
vehicle in its own lane. Do not
swing wide or cross the
center line.
. Be alert on top of hills;
something could be in your lane
(e.g., stalled car, accident).
. Pay attention to special road
signs (e.g., falling rocks area,
winding roads, long grades,
passing or no-passing zones)
and take appropriate action.
Winter Driving
Driving on Snow or Ice
Snow or ice between the tires and
the road creates less traction or
grip, so drive carefully. Wet ice can
occur at about 0 °C (32 °F) when
freezing rain begins to fall. Avoid
driving on wet ice or in freezing rain
until roads can be treated.
For Slippery Road Driving:
.Accelerate gently. Accelerating
too quickly causes the wheels to
spin and makes the surface
under the tires slick.
. Turn on Traction Control. See
Traction Control/Electronic
Stability Control 0236.
. The Antilock Brake System
(ABS) improves vehicle stability
during hard stops, but the
brakes should be applied sooner
than when on dry pavement.
See Antilock Brake System
(ABS) 0233.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Driving and Operating 225
Engine Heater
The engine heater can provide
easier starting and better fuel
economy during engine warm-up in
cold weather conditions at or below
0 °F (−18 °C). Vehicles with an
engine heater should be plugged in
at least four hours before starting.
Some models may have an internal
thermostat in the cord which will
prevent engine heater operation at
temperatures above 0 °F (−18 °C).
{Warning
Do not plug in the engine block
heater while the vehicle is parked
in a garage or under a carport.
Property damage or personal
injury may result. Always park the
vehicle in a clear open area away
from buildings or structures.
To Use the Engine Heater
1. Turn off the engine.
2. Open the hood and unwrap theelectrical cord. The bundled
cord is on the driver side of the
engine compartment, in front of
the battery. See Engine
Compartment Overview 0283.
Check the heater cord for
damage. If it is damaged, do
not use it. See your dealer for
a replacement. Inspect the
cord for damage yearly.
3. Plug the cord into a normal, grounded 110-volt AC outlet.
{Warning
Improper use of the heater cord
or an extension cord can damage
the cord and may result in
overheating and fire.
. Plug the cord into a
three-prong electrical utility
receptacle that is protected
by a ground fault detection
function. An ungrounded
outlet could cause an
electric shock.
. Use a weatherproof,
heavy-duty, 15 amp-rated
extension cord if needed.
Failure to use the
recommended extension
cord in good operating
condition, or using a
damaged heater or
extension cord, could make
(Continued)

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
234 Driving and Operating
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
system when the engine is not
running.
The system has a
Yor PARK
Electric Parking Brake light, and a
8
Service Parking Brake light or
message.
See Electric Parking Brake Light
0 139 andService Electric Parking
Brake Light (Uplevel and Midlevel
Cluster Only) 0139.
Before leaving the vehicle, check for
the
Yor 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
Yor PARK light will flash and
then stay on once the EPB is fully
applied. If the
Yor 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
Yor
PARK light is flashing. See your
dealer. See Electric Parking Brake
Light 0139.
If the
8light or message is on,
press the EPB switch and hold it.
Continue to hold the switch until
the
Yor PARK light remains on.
If the
8light or message 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.
If the EPB fails to apply, block the
rear wheels to prevent vehicle
movement.
EPB Release
To release the EPB:
1. Turn the ignition on or to ACC/ ACCESSORY.
2. Apply and hold the brake pedal.
3. Press the EPB switch momentarily.
The EPB is released when the
Y
or PARK light is off.
If the
8light or message is on,
release the EPB by pressing and
holding the EPB switch. Continue to
hold the switch until the
Yor

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
236 Driving and Operating
If Extended Hold is selected, it will
hold the vehicle for five minutes
unless the driver door is opened
and the driver seat belt is unbuckled
prior to releasing the brake pedal.
When deactivated after five minutes,
or if it is deactivated when the driver
seat belt is unlatched or the driver
door is opened, the Electric Parking
Brake will engage to prevent vehicle
movement.Ride Control Systems
Traction Control/
Electronic Stability
Control
System Operation
The vehicle has a Traction Control
System (TCS) and StabiliTrak®, an
electronic stability control system.
These systems help limit wheel spin
and assist the driver in maintaining
control, especially on slippery road
conditions.
TCS activates if it senses that any
of the drive wheels are spinning or
beginning to lose traction. When this
happens, TCS applies the brakes to
the spinning wheels and reduces
engine power to limit wheel spin.
StabiliTrak activates when the
vehicle senses a difference between
the intended path and the direction
the vehicle is actually traveling.
StabiliTrak selectively applies
braking pressure to any one of the vehicle wheel brakes to assist the
driver in keeping the vehicle on the
intended path.
If cruise control is being used and
TCS or StabiliTrak begins to limit
wheel spin, cruise control will
disengage. Cruise control may be
turned back on when road
conditions allow. TCS and
StabiliTrak will automatically turn on
when cruise control is set.
Both systems come on
automatically when the vehicle is
started and begins to move. The
systems may be heard or felt while
they are operating or while
performing diagnostic checks. This
is normal and does not mean there
is a problem with the vehicle.
It is recommended to leave both
systems on for normal driving
conditions, but it may be necessary
to turn TCS off if the vehicle gets
stuck in sand, mud, ice, or snow.
See
If the Vehicle Is Stuck 0217
and “Turning the Systems Off and
On” later in this section.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
268 Driving and Operating
federal specifications, but emission
control system performance may be
affected. The malfunction indicator
lamp could turn on and the vehicle
may not pass a smog-check test.
SeeMalfunction Indicator Lamp
(Check Engine Light) 0136. If this
occurs, return to your authorized
dealer for diagnosis. If it is
determined that the condition is
caused by the type of fuel used,
repairs may not be covered by the
vehicle warranty.
Fuels in Foreign
Countries
The U.S., Canada, and Mexico post
fuel octane ratings in anti-knock
index (AKI). For fuel not to use in a
foreign country, see “Prohibited
Fuels” inFuel 0267.
Fuel Additives
To keep fuel systems clean, TOP
TIER detergent gasoline is
recommended. See Fuel0267. If TOP TIER detergent gasoline is
not available, one bottle of GM Fuel
System Treatment Cleaner added to
the fuel tank at every engine oil
change, can help. GM Fuel System
Treatment Cleaner is the only
gasoline additive recommended by
General Motors. It is available at
your dealer.
Filling the Tank
{Warning
Fuel vapors and fuel fires burn
violently and can cause injury or
death.
. To help avoid injuries to you
and others, read and follow
all the instructions on the
fuel pump island.
. Turn off the engine when
refueling.
. Keep sparks, flames, and
smoking materials away
from fuel.
(Continued)
Warning (Continued)
.Do not leave the fuel pump
unattended.
. Do not use a cell phone
while refueling.
. Do not reenter the vehicle
while pumping fuel.
. Keep children away from
the fuel pump and never let
children pump fuel.
. Fuel can spray out if the
refueling nozzle is inserted
too quickly. This spray can
happen if the tank is nearly
full, and is more likely in hot
weather. Insert the refueling
nozzle slowly and wait for
any hiss noise to stop prior
to beginning to flow fuel.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Driving and Operating 271
.Do not tow a trailer during the
first 800 km (500 mi), to prevent
damage to the engine, axle or
other parts.
. Then, during the first 800 km
(500 mi) trailer towing, do not
drive over 80 km/h (50 mph) and
do not make starts at full throttle.
. The vehicle can tow in D (Drive)
but Manual Mode is
recommended. See Manual
Mode 0231. Use a lower gear if
the transmission shifts too often.
. Turn off Parking Assist and Rear
Cross Traffic Alert (RCTA) when
towing.
. Turn off Lane Keep Assist (LKA)
when towing.
. Do not use Adaptive Cruise
Control (ACC) when towing a
trailer.{Warning
When towing a trailer, exhaust
gases may collect at the rear of
the vehicle and enter if the
liftgate, trunk/hatch, or rear-most
window is open.
When towing a trailer:
. Do not drive with the
liftgate, trunk/hatch,
or rear-most window open.
. Fully open the air outlets on
or under the instrument
panel.
. Also adjust the climate
control system to a setting
that brings in only outside
air. See “Climate Control
Systems” in the Index.
For information about carbon
monoxide, see Engine Exhaust
0 228.
Towing a trailer requires a certain
amount of experience. The
combination you are driving is longer and not as responsive as the
vehicle itself. Get acquainted with
the handling and braking of the rig
before setting out for the open road.
Before starting, check all trailer hitch
parts and attachments, safety
chains, electrical connectors, lamps,
tires, and mirrors. If the trailer has
electric brakes, start the
combination moving and then apply
the trailer brake controller by hand
to be sure the brakes work.
During the trip, check occasionally
to be sure that the load is secure
and the lamps and any trailer
brakes still work.
Towing with a Stability Control
System
When towing, the sound of the
stability control system might be
heard. The system is reacting to the
vehicle movement caused by the
trailer, which mainly occurs during
cornering. This is normal when
towing heavier trailers.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
272 Driving and Operating
Following Distance
Stay at least twice as far behind the
vehicle ahead as you would when
driving the vehicle without a trailer.
This can help to avoid situations
that require heavy braking and
sudden turns.
Passing
More passing distance is needed
when towing a trailer. Because the
rig is longer, it is necessary to go
farther beyond the passed vehicle
before returning to the lane.
Backing Up
Hold the bottom of the steering
wheel with one hand. To move the
trailer to the left, move your hand to
the left. To move the trailer to the
right, move your hand to the right.
Always back up slowly and,
if possible, have someone
guide you.
Making TurnsCaution
Making very sharp turns while
trailering could cause the trailer to
come in contact with the vehicle.
The vehicle could be damaged.
Avoid making very sharp turns
while trailering.
When turning with a trailer, make
wider turns than normal so the
trailer will not strike soft shoulders,
curbs, road signs, trees, or other
objects. Use the turn signal well in
advance and avoid jerky or sudden
maneuvers.
Turn Signals When Towing a
Trailer
The turn signal indicators on the
instrument cluster flash whenever
signaling a turn or lane change.
Properly hooked up, the trailer
lamps also flash, telling other
drivers the vehicle is turning,
changing lanes, or stopping. When towing a trailer, the arrows on
the instrument cluster flash for turns
even if the bulbs on the trailer are
burned out. Check occasionally to
be sure the trailer bulbs are still
working.
Driving on Grades
Reduce speed and shift to a lower
gear before starting down a long or
steep downgrade. If the
transmission is not shifted down, the
brakes might have to be used so
much that they would get hot and no
longer work well.
The vehicle can tow in D (Drive).
Use a lower gear if the transmission
shifts too often.
The Tow/Haul Mode may be used if
the transmission shifts too often.
See
Tow/Haul Mode 0232.
When towing at high altitude on
steep uphill grades, engine coolant
boils at a lower temperature than at
normal altitudes. If the engine is
turned off immediately after towing
at high altitude on steep uphill
grades, the vehicle could show
signs similar to engine overheating.