2018 BUICK LACROSSE check engine light

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
Instruments and Controls 125
Cruise Control Light
The cruise control light is white
when the cruise control is on and
ready, and turns green when the
cruise control is set and active.
SeeCruise Control 0193.
Adaptive Cruise Control Light
This light is white when the Adaptive
Cruise Control (ACC, if equipped) is
on and ready, and turns green when
the ACC is set and active. See
Adaptive Cruise Control 0195.
Door Ajar Light
This light comes on when a door is
open or not securely latched. Before
driving, check that all doors are
properly closed.
Information Displays
Power Flows (eAssist)
To view the Power Flow screens in
the infotainment display, touch
[
on the Home page or on the
Application Tray on the top of the
infotainment display. Then touch
FLOW at the bottom of the display.
The Power Flow screens indicate
the current operating condition. The
screens show energy flow between
the engine, generator, and high
voltage battery. These components
will be highlighted when they are
active.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
132 Instruments and Controls
If You Cannot See the HUD
Image When the Ignition Is On
Check that:
.Nothing is covering the
HUD lens.
. HUD brightness setting is not
too dim or too bright.
. HUD is adjusted to the proper
height.
. Polarized sunglasses are
not worn.
. Windshield and HUD lens are
clean.
If the HUD image is not correct,
contact your dealer.
The windshield is part of the HUD
system. See Windshield
Replacement 0249.
Vehicle Messages
Messages displayed on the DIC
indicate the status of the vehicle or
some action that may be needed to
correct a condition. Multiple
messages may appear one after
another.
The messages that do not require
immediate action can be
acknowledged and cleared by
pressing
V. The messages that
require immediate action cannot be
cleared until that action is
performed.
All messages should be taken
seriously; clearing the message
does not correct the problem.
If a SERVICE message appears,
see your dealer.
Follow the instructions given in the
messages. The system displays
messages regarding the following
topics:
. Service Messages
. Fluid Levels
. Vehicle Security .
Brakes
. Ride Control Systems
. Driver Assistance Systems
. Cruise Control
. Lighting and Bulb Replacement
. Wiper/Washer Systems
. Doors and Windows
. Seat Belts
. Airbag Systems
. Engine and Transmission
. Tire Pressure
. Battery
Engine Power Messages
ENGINE/PROPULSION POWER
IS REDUCED
This message displays when the
vehicle's propulsion power is
reduced. Reduced propulsion power
can affect the vehicle's ability to
accelerate. If this message is on,
but there is no observed reduction
in performance, proceed to your
destination. The performance may

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
164 Driving and Operating
Warning (Continued)
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
wet enough and you are going fast
enough. When the vehicle is
hydroplaning, it has little or no
contact with the road.There is no hard and fast rule about
hydroplaning. The best advice is to
slow down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet
weather driving tips include:
.
Allow extra following distance.
. Pass with caution.
. Keep windshield wiping
equipment in good shape.
. Keep the windshield washer fluid
reservoir filled.
. Have good tires with proper
tread depth. See Tires0259.
. Turn off cruise control.
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. 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.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
Driving and Operating 187
Drive Systems
All-Wheel Drive
Vehicles with this feature always
send engine power to all four
wheels. It is fully automatic, and
adjusts itself as needed for road
conditions.
All-Wheel Drive (AWD) system
performance will be automatically
reduced when the compact spare
tire is in use. To restore full AWD
performance, and prevent excessive
wear to the AWD system, replace
the compact spare tire with a
full-size tire as soon as possible.
SeeCompact Spare Tire 0292.
Brakes
Antilock Brake
System (ABS)
This vehicle has an Antilock Brake
System (ABS), an advanced
electronic braking system that helps
prevent a braking skid.
When the vehicle begins to drive
away, ABS checks itself.
A momentary motor or clicking noise
may be heard while this test is going
on, and it may even be noticed that
the brake pedal moves a little. This
is normal.
If there is a problem with ABS, this
warning light stays on. See Antilock
Brake System (ABS) Warning Light
0 120. If driving safely on a wet road and it
becomes necessary to slam on the
brakes and continue braking to
avoid a sudden obstacle, a
computer senses the wheels are
slowing down. If one of the wheels
is about to stop rolling, the computer
will separately work the brakes at
each wheel.
ABS can change the brake pressure
to each wheel, as required, faster
than any driver could. This can help
you steer around the obstacle while
braking hard.
As the brakes are applied, the
computer keeps receiving updates
on wheel speed and controls
braking pressure accordingly.
Remember: ABS does not change
the time needed to get a foot up to
the brake pedal or always decrease
stopping distance. If you get too
close to the vehicle in front of you,
there will not be enough time to
apply the brakes if that vehicle
suddenly slows or stops. Always
leave enough room up ahead to
stop, even with ABS.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
188 Driving and Operating
Using ABS
Do not pump the brakes. Just hold
the brake pedal down firmly and let
ABS work. You may hear the ABS
pump or motor operating and feel
the brake pedal pulsate. This is
normal.
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 Electric Parking Brake (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 red parking brake
status light and an amber parking
brake warning light. There are also
parking brake-related Driver
Information Center (DIC) messages.
In case of insufficient electrical
power, the EPB cannot be applied
or released.
Before leaving the vehicle, check
the red parking brake status 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 red parking brake status light
will flash and then stay on once the
EPB is fully applied. If the red parking brake status 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 red
parking brake status light is flashing.
See your dealer.
If the amber parking brake warning
light is on, press the EPB switch.
Continue to hold the switch until the
red parking brake status light
remains on. If the amber parking
brake warning light is 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

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
Driving and Operating 191
vehicle wheel brakes to assist the
driver in keeping the vehicle on the
intended path.
If cruise control is being used and
traction control or StabiliTrak begins
to limit wheel spin, cruise control will
disengage. Cruise control may be
turned back on when road
conditions allow.
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.
SeeIf the Vehicle Is Stuck 0166
and “Turning the Systems Off and
On” later in this section.
The indicator light for both systems
is in the instrument cluster. This
light will:
.
Flash when TCS is limiting
wheel spin.
. Flash when StabiliTrak is
activated.
. Turn on and stay on when either
system is not working.
If either system fails to turn on or to
activate, a message displays in the
Driver Information Center (DIC), and
dcomes on and stays on to
indicate that the system is inactive
and is not assisting the driver in
maintaining control. The vehicle is
safe to drive, but driving should be
adjusted accordingly. If
dcomes on and stays on:
1. Stop the vehicle.
2. Turn the engine off and wait 15 seconds.
3. Start the engine.
Drive the vehicle. If
dcomes on
and stays on, the vehicle may need
more time to diagnose the problem.
If the condition persists, see your
dealer.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
Driving and Operating 219
may not pass a smog-check test.
SeeMalfunction Indicator Lamp
(Check Engine Light) 0117. 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 0218.
Fuel Additives
To keep fuel systems clean, TOP
TIER detergent gasoline is
recommended. See Fuel0218.
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.
. Do not leave the fuel pump
unattended.
. Do not use a cell phone
while refueling.
. Do not reenter the vehicle
while pumping fuel.
(Continued)
Warning (Continued)
.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.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
226 Driving and Operating
Conversions and
Add-Ons
Add-On Electrical
Equipment
{Warning
The Data Link Connector (DLC) is
used for vehicle service and
Emission Inspection/Maintenance
testing. SeeMalfunction Indicator
Lamp (Check Engine Light) 0117.
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 079 and Adding Equipment
to the Airbag-Equipped Vehicle
0 79.