Black plate (2,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
2015 Buick LaCrosse Owner ManualM
Vehicle Care. . . . . . . . . . . . . . . . . 10-1
General Information . . . . . . . . . . 10-2
Vehicle Checks . . . . . . . . . . . . . . . 10-4
Headlamp Aiming . . . . . . . . . . . 10-31
Bulb Replacement . . . . . . . . . . 10-31
Electrical System . . . . . . . . . . . . 10-34
Wheels and Tires . . . . . . . . . . . 10-42
Jump Starting . . . . . . . . . . . . . . . 10-78
Towing the Vehicle . . . . . . . . . . 10-82
Appearance Care . . . . . . . . . . . 10-85
Service and Maintenance . . . 11-1
General Information . . . . . . . . . . 11-1
Maintenance Schedule . . . . . . . 11-2
Special Application
Services . . . . . . . . . . . . . . . . . . . . 11-8
Additional Maintenance
and Care . . . . . . . . . . . . . . . . . . . . 11-8
Recommended Fluids, Lubricants, and Parts . . . . . . 11-12
Maintenance Records . . . . . . . 11-14 Technical Data
. . . . . . . . . . . . . . . 12-1
Vehicle Identification . . . . . . . . . 12-1
Vehicle Data . . . . . . . . . . . . . . . . . . 12-2
Customer Information . . . . . . . 13-1
Customer Information . . . . . . . . 13-1
Reporting Safety Defects . . . . 13-12
Vehicle Data Recording and
Privacy . . . . . . . . . . . . . . . . . . . . 13-14
OnStar . . . . . . . . . . . . . . . . . . . . . . . 14-1
OnStar Overview . . . . . . . . . . . . . 14-1
OnStar Services . . . . . . . . . . . . . . 14-2
OnStar Additional Information . . . . . . . . . . . . . . . . . . 14-6
Index . . . . . . . . . . . . . . . . . . . . . i-1
Black plate (23,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
In Brief 1-23
E85 or FlexFuel
Vehicles with a yellow fuel cap can
use either unleaded gasoline or
ethanol fuel containing up to 85%
ethanol (E85). SeeE85 or FlexFuel
on page 9-60. For all other vehicles,
use only the unleaded gasoline
described under Fuel on page 9-58.
Driving for Better Fuel
Economy
Driving habits can affect fuel
mileage. Here are some driving tips
to get the best fuel economy
possible.
.Avoid fast starts and accelerate
smoothly.
.Brake gradually and avoid
abrupt stops.
.Avoid idling the engine for long
periods of time.
.When road and weather
conditions are appropriate, use
cruise control.
.Always follow posted speed
limits or drive more slowly when
conditions require.
.Keep vehicle tires properly
inflated.
.Combine several trips into a
single trip.
.Replace the vehicle's tires with
the same TPC Spec number
molded into the tire's sidewall
near the size.
.Follow recommended scheduled
maintenance.
Roadside Assistance
Program
U.S.: 1-800-252-1112
TTY Users (U.S. Only):
1-888-889-2438
Canada: 1-800-268-6800
New Buick owners are automatically
enrolled in the Roadside Assistance
Program. See
Roadside Assistance Program
on page 13-5.
OnStar®
This vehicle may be equipped with a
comprehensive, in-vehicle system
that can connect to a live OnStar
Advisor for Emergency, Security,
Navigation, Connection, and
Diagnostic Services. OnStar
services may require a paid
subscription. See OnStar Overview
on page 14-1.
Black plate (32,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
3-32 Seats and Restraints
Your dealer and the service manual
have information about the location
of the airbag sensors, sensing and
diagnostic module, and airbag
wiring.
In addition, the vehicle has a
passenger sensing system for the
front outboard passenger position,
which includes sensors that are part
of the passenger seat. The
passenger sensing system may not
operate properly if the original seat
trim is replaced with non-GM
covers, upholstery, or trim; or with
GM covers, upholstery, or trim
designed for a different vehicle. Any
object, such as an aftermarket seat
heater or a comfort-enhancing pad
or device, installed under or on top
of the seat fabric, could also
interfere with the operation of the
passenger sensing system. This
could either prevent proper
deployment of the passenger
airbag(s) or prevent the passenger
sensing system from properlyturning off the passenger airbag(s).
See
Passenger Sensing System on
page 3-26.
If the vehicle has rollover roof-rail
airbags, see Different Size Tires
and Wheels on page 10-60 for
additional important information.
If you have to modify your vehicle
because you have a disability and
you have questions about whether
the modifications will affect the
vehicle's airbag system, or if you
have questions about whether the
airbag system will be affected if the
vehicle is modified for any other
reason, call Customer Assistance.
See Customer Assistance Offices
on page 13-3.
Airbag System Check
The airbag system does not need
regularly scheduled maintenance or
replacement. Make sure the airbag
readiness light is working. See
Airbag Readiness Light on
page 5-14.
{Caution
If an airbag covering is damaged,
opened, or broken, the airbag
may not work properly. Do not
open or break the airbag
coverings. If there are any
opened or broken airbag
coverings, have the airbag
covering and/or airbag module
replaced. For the location of the
airbags, see Where Are the
Airbags? on page 3-22. See your
dealer for service.
Replacing Airbag System
Parts after a Crash
{Warning
A crash can damage the airbag
systems in the vehicle.
A damaged airbag system may
not work properly and may not
(Continued)
Black plate (23,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Instruments and Controls 5-23
{Caution
The engine coolant temperature
warning light indicates that the
vehicle has overheated. Driving
with this light on can damage the
engine and it may not be covered
by the vehicle warranty. See
Engine Overheating on
page 10-21.
The engine coolant temperature
warning light comes on when the
engine has overheated.
If this happens, pull over and turn
off the engine as soon as possible.
See Engine Overheating on
page 10-21.
Tire Pressure Light
For vehicles with the Tire Pressure
Monitor System (TPMS), this light
comes on briefly when the engine is
started. It provides information
about tire pressures and the TPMS.
When the Light Is On Steady
This indicates that one or more of
the tires are significantly
underinflated.
A Driver Information Center (DIC)
tire pressure message may also
display. See Tire Messages on
page 5-43. Stop as soon as
possible, and inflate the tires to the
pressure value shown on the Tire
and Loading Information label. See
Tire Pressure on page 10-50. When the Light Flashes First and
Then Is On Steady
If the light flashes for about a minute
and then stays on, there may be a
problem with the TPMS. If the
problem is not corrected, the light
will come on at every ignition cycle.
See
Tire Pressure Monitor
Operation on page 10-52.
Engine Oil Pressure Light
{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, have the vehicle serviced.
Always follow the maintenance
schedule for changing engine oil.
Black plate (38,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
5-38 Instruments and Controls
Engine Cooling System
Messages
A/C OFF DUE TO HIGH
ENGINE TEMP
This message displays when the
engine coolant becomes hotter than
the normal operating temperature.
To avoid added strain on a hot
engine, the air conditioning
compressor automatically turns off.
When the coolant temperature
returns to normal, the air
conditioning compressor turns back
on. You can continue to drive the
vehicle.
If this message continues to appear,
have the system repaired by your
dealer as soon as possible to avoid
damage to the engine.
COOLANT LEVEL LOW ADD
COOLANT
This message will display if the
coolant is low. SeeEngine Coolant
on page 10-19.
ENGINE OVERHEATED —
IDLE ENGINE
This message displays when the
engine coolant temperature is too
hot. Stop and allow the vehicle to
idle until it cools down.
ENGINE OVERHEATED —
STOP ENGINE
This message displays and a
continuous chime sounds if the
engine cooling system reaches
unsafe temperatures for operation.
Stop and turn off the vehicle as
soon as it is safe to do so to avoid
severe damage. This message
clears when the engine has cooled
to a safe operating temperature.
Engine Oil Messages
CHANGE ENGINE OIL SOON
This message displays when the
engine oil needs to be changed.
When you change the engine oil, be
sure to reset the oil life system. See
Engine Oil Life System on page 10-13,
Driver Information
Center (DIC) on page 5-28, Engine
Oil on page 10-11, and Maintenance
Schedule on page 11-2.
ENGINE OIL HOT, IDLE
ENGINE
This message displays when the
engine oil temperature is too hot.
Stop and allow the vehicle to idle
until it cools down.
ENGINE OIL LOW —ADD OIL
On some vehicles, this message
displays when the engine oil level
may be too low. Check the oil level
before filling to the recommended
level. If the oil is not low and this
message remains on, take the
vehicle to your dealer for service.
See Engine Oil on page 10-11.
OIL PRESSURE LOW —STOP
ENGINE
This message displays if low oil
pressure levels occur. Stop the
vehicle as soon as safely possible
and do not operate it until the cause
Black plate (65,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Driving and Operating 9-65
Vehicles can tow in D (Drive). Shift
the transmission to a lower gear if
the transmission shifts too often
under heavy loads and/or hilly
conditions.
When towing at high altitude on
steep uphill grades, consider the
following: Engine coolant will boil 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 may show signs similar to
engine overheating. To avoid this,
let the engine run while parked,
preferably on level ground, with the
automatic transmission in P (Park)
for a few minutes before turning the
engine off. If the overheat warning
comes on, seeEngine Overheating
on page 10-21.Parking on Hills
{Warning
Parking the vehicle on a hill with
the trailer attached can be
dangerous. If something goes
wrong, the rig could start to move.
People can be injured, and both
the vehicle and the trailer can be
damaged. When possible, always
park the rig on a flat surface.
If parking the rig on a hill:
1. Press the brake pedal, but do not shift into P (Park) yet. Turn
the wheels into the curb if facing
downhill or into traffic if facing
uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the regular brakes
until the chocks absorb the load. 4. Reapply the brake pedal. Then
apply the parking brake and shift
into P (Park).
5. Release the brake pedal.Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
2. Start the engine.
3. Shift into a gear.
4. Release the parking brake.
5. Let up on the brake pedal.
6. Drive slowly until the trailer is clear of the chocks.
7. Stop and have someone pick up and store the chocks.
Maintenance when Trailer
Towing
The vehicle needs service more
often when pulling a trailer. See
Maintenance Schedule on
page 11-2. Things that are
especially important in trailer
operation are automatic
transmission fluid, engine oil, axle
Black plate (15,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Vehicle Care 10-15
Automatic Transmission
Fluid
How to Check Automatic
Transmission Fluid
It is not necessary to check the
transmission fluid level.
A transmission fluid leak is the only
reason for fluid loss. If a leak
occurs, take the vehicle to your
dealer service department and have
it repaired as soon as possible.
There is a special procedure for
checking and changing the
transmission fluid. Because this
procedure is difficult, you should
have this done at your dealer
service department. Contact your
dealer for additional information or
the procedure can be found in the
service manual. To purchase a
service manual, seeService
Publications Ordering Information
on page 13-11. Change the fluid at the intervals
listed in
Maintenance Schedule on
page 11-2, and be sure to use the
fluid listed in Recommended Fluids
and Lubricants on page 11-12.Engine Air Cleaner/Filter
The engine air cleaner/filter is in the
engine compartment on the
passenger side of the vehicle. See
Engine Compartment Overview on
page 10-6.
When to Inspect the Engine Air
Cleaner/Filter
Inspect the air cleaner/filter at the
scheduled maintenance intervals
and replace it at the first oil change
after each 80 000 km (50,000 mi)
interval. See Maintenance Schedule
on page 11-2. If you are driving in
dusty/dirty conditions, inspect the
filter at each engine oil change.
How to Inspect the Engine Air
Cleaner/Filter
To inspect the air cleaner/filter,
remove the filter from the vehicle
and lightly shake the filter to release
loose dust and dirt. If the filter
remains covered with dirt, a new
filter is required.
2.4L L4 Engine
1. Screws
2. Air Duct Clamp
3. Electrical Connector
Black plate (30,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
10-30 Vehicle Care
.To check the P (Park)
mechanism's holding ability:
With the engine running, shift to
P (Park). Then release the
parking brake followed by the
regular brake.
Contact your dealer if service is
required.
Wiper Blade Replacement
Windshield wiper blades should be
inspected for wear and cracking.
See Maintenance Schedule on
page 11-2 for more information.
Replacement blades come in
different types and are removed in
different ways. For proper type and
length, see Maintenance
Replacement Parts on page 11-13. To replace the windshield wiper
blade:
1. Pull the windshield wiper
assembly away from the
windshield.
2. Lift up on the latch in the middleof the wiper blade where the
wiper arm attaches.
3. With the latch open, pull the wiper blade down toward the
windshield far enough to release
it from the J-hooked end of the
wiper arm. 4. Remove the wiper blade.
Allowing the wiper blade arm to
touch the windshield when no
wiper blade is installed could
damage the windshield. Any
damage that occurs would not
be covered by the vehicle
warranty. Do not allow the wiper
blade to touch the windshield.
5. Reverse Steps 1–3 for wiper blade replacement.
Windshield Replacement
The windshield is part of the HUD
system. If the vehicle has to have
the windshield replaced, get one
that is designed for HUD or the
HUD image may look out of focus.