2015 BUICK LACROSSE heater

Black plate (18,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
10-18 Vehicle Care
3.6L V6 Engine AWD
1. Engine Cooling Fans (Outof View)
2. Coolant Surge Tank and Pressure Cap
3.6L V6 Engine FWD
1. Engine Cooling Fans (Outof View)
2. Coolant Surge Tank and Pressure Cap
{Warning
An electric engine cooling fan
under the hood can start up even
when the engine is not running
and can cause injury. Keep
hands, clothing, and tools away
from any underhood electric fan.
{Warning
Heater and radiator hoses, and
other engine parts, can be very
hot. Do not touch them. If you do,
you can be burned.
Do not run the engine if there is a
leak. If you run the engine, it
could lose all coolant. That could
cause an engine fire, and you
could be burned. Get any leak
fixed before you drive the vehicle.
{Caution
Using coolant other than
DEX-COOL®can cause
premature engine, heater core,
or radiator corrosion. In addition,
the engine coolant could require
changing sooner. Any repairs
would not be covered by the
(Continued)

Black plate (22,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
10-22 Vehicle Care
If the decision is made not to lift the
hood when this warning appears,
get service help right away. See
Roadside Assistance Program on
page 13-5.
If the decision is made to lift the
hood, make sure the vehicle is
parked on a level surface.
Then check to see if the engine
cooling fans are running. If the
engine is overheating, the fans
should be running. If not, do not
continue to run the engine and have
the vehicle serviced.
{Caution
Running the engine without
coolant may cause damage or a
fire. Vehicle damage would not be
covered by the vehicle warranty.
If Steam Is Coming from the
Engine Compartment
SeeOverheated Engine Protection
Operating Mode on page 10-23 for
information on driving to a safe
place in an emergency.
If No Steam Is Coming from
the Engine Compartment
If an engine overheat warning is
displayed but no steam can be seen
or heard, the problem might not be
too serious. Sometimes the engine
can get a little too hot when the
vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.
.Idles for long periods in traffic.
.Tows a trailer. If the overheat warning displays with
no sign of steam:
1. Turn the air conditioning off.
2. Turn the heater on to the highest
temperature and to the highest
fan speed. Open the windows as
necessary.
3. When it is safe to do so, pull off the road, shift to P (Park) or
N (Neutral), and let the
engine idle.
If the temperature overheat gauge is
no longer in the overheat zone or an
engine coolant temperature warning
light no longer displays, the vehicle
can be driven. Continue to drive the
vehicle slowly for about 10 minutes.
Keep a safe vehicle distance from
the vehicle in front. If the warning
does not come back on, continue to
drive normally and have the cooling
system checked for proper fill and
function.

Black plate (37,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Vehicle Care 10-37
J-CaseFuses Usage
25 Rear Heated Seats
26 Antilock Brake System Pump
27 Electric Parking Brake
28 Rear Window Defogger
41 Brake Vacuum Pump
42 Cooling Fan K2
43 Not Used
44 Transmission Auxiliary Oil Pump
(eAssist)
45 Cooling Fan K1
59 AIR Pump Mini Fuses Usage
1 Transmission Control Module —
Battery
2 Engine Control Module Battery
3 Air Conditioning Compressor Clutch
5 Engine Control Module Run/Crank
7 Long Range Radar/ Front Camera
8 Ignition Coils –Even
(Six Cylinder
Engine), Ignition
Coils –All (Four
Cylinder Engine)
9 Ignition Coils –Odd
(Six Cylinder
Engine) Mini Fuses Usage
10 Engine Control Module–Switched
Battery (from Engine
Control Module
Relay)
11 Six Cylinder Engine: Post Catalytic
Converter Oxygen
Sensor Heater,
Mass Air Flow
Sensor, FlexFuel
Sensor, Secondary
Air Induction
Solenoid
13 Crank for Transmission
Control Module/Fuel
Pump Power/
Chassis Control
Module (eAssist)

Black plate (38,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
10-38 Vehicle Care
Mini Fuses Usage14 Cabin Heater Coolant Pump
(eAssist)/Secondary
Air Injector/
Secondary Air
Injector with
Pressure Sensor
15 Motor Generator Unit Coolant Pump
(eAssist)
16 Run/Crank for eAssist Power
Inverter Module
17 Not Used
18 Sunshade Module, Vehicle Air
Purification System,
Ventilated Seats
20 Heated Steering Wheel (non eAssist) Mini Fuses Usage
23 Variable Effort Steering (if
equipped) or eAssist
Power Inverter
Module
29 Heated Seat, Left/ Power Lumbar
30 Heated Seat, Right/ Power Pack Cooling
Fan (eAssist)
31 All-Wheel Drive, Electronic
Suspension Control
32 Body Control Module 6
33 Memory Seat –
Front
34 Antilock Brake System Valves
35 Amplifier
36 Adaptive Forward Lighting (AFL)
Motors–Battery Mini Fuses Usage
37 Right High Beam
38 Left High Beam
46 Cooling Fan Relay
47 Six Cylinder Engine: Pre Catalytic
Converter Oxygen
Sensor Heater,
Canister Purge
Solenoid. Four
Cylinder Engine: Pre
and Post Catalytic
Converter Oxygen
Sensor Heaters,
Canister Purge
Solenoid
48 Fog Lamps
49 Right High Intensity Discharge
Headlamp
50 Left High Intensity Discharge
Headlamp
51 Horn

Black plate (39,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Vehicle Care 10-39
Mini Fuses Usage52 Cluster Run/Crank
53 Run/Crank for Inside Rearview Mirror,
Rear Vision Camera,
Air Quality Sensor,
Aero Shutter Motor
54 Run/Crank for: Heating, Ventilation
and Air
Conditioning,
Headlamp Switch
55 Outside Rearview Mirror, Universal
Remote System,
Front Window
Switches
56 Windshield Washer
60 Heated Mirror
62 Canister Vent
64 Adaptive Forward Lighting (AFL)
Module–Battery
65 Not Used Mini Fuses Usage
66 AIR Solenoid (eAssist)
67 Fuel Pump Power Module/Chassis
Control Module
69 Regulated Voltage Control Sensor
70 Parking Assist/Side Blind Zone
71 Passive Entry/ Passive Start
Mini Relays Usage 7 Engine Control Module
9 Cooling Fan
13 Cooling Fan
15 Run/Crank
16 AIR Pump
17 Rear Window Defogger Micro
Relays Usage
1 Air Conditioning Compressor Clutch
2 Starter
4 Wiper Speed
5 Wiper Control
6 Cabin Heater Coolant Pump
(eAssist)/Secondary
Air Injector/
Secondary Air
Injector with
Pressure Sensor
10 Cooling Fan
14 Headlamp Low Beam
Ultra Micro Relays Usage
11 Transmission Auxiliary Oil Pump
(eAssist)

Black plate (41,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Vehicle Care 10-41
FusesUsage
9 Body Control Module 4
10 Body Control Module 8
(J-Case Fuse)
11 Front Heater Ventilation Air
Conditioning/Blower
(J-Case Fuse)
12 Passenger Seat (Circuit Breaker)
13 Driver Seat (Circuit Breaker)
14 Diagnostic Link Connector
15 Airbag/Automatic Occupant Sensing
16 Trunk
17 Heater Ventilation Air Conditioning
Controller Fuses
Usage
18 Pre-Fuse for Fuses 4 and 5
19 Center Stack Displays, Head-Up
Display, Right
Steering Wheel
Control Switch, Rear
Seat Infotainment
Display (eAssist),
HVAC Center Stack
Displays
20 Rear Seat Entertainment
Display/Rear Seat
Audio
21 Instrument Cluster
22 Discrete Logic Ignition Switch
23 Body Control Module 3
24 Body Control Module 2 Fuses
Usage
25 Rear Heater Ventilation Air
Conditioning/Blower
26 AC/DC Inverter
Relays Usage
R1 Trunk Relay
R2 Not Used
R3 Power Outlet Relay

Black plate (4,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
i-4 INDEX
Driving (cont'd)Vehicle Load Limits . . . . . . . . . . . 9-10
Wet Roads . . . . . . . . . . . . . . . . . . . . 9-6
Winter . . . . . . . . . . . . . . . . . . . . . . . . . 9-8
Dual Automatic Climate Control System . . . . . . . . . . . . . . . . 8-1
E
E85 or FlexFuel . . . . . . . . . . . . . . . 9-60
Electric Parking Brake Light . . . 5-20
Electrical Equipment,Add-On . . . . . . . . . . . . . . . . . . . . . . 9-68
Electrical System Engine CompartmentFuse Block . . . . . . . . . . . . . . . . 10-36
Fuses and Circuit
Breakers . . . . . . . . . . . . . . . . . . 10-35
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . . 10-40
Overload . . . . . . . . . . . . . . . . . . . 10-35
Emergency OnStar
®. . . . . . . . . . . . . . . . . . . . . . 14-2
Energy Information . . . . . . . . . . . . 5-27 Engine
Air Cleaner/Filter . . . . . . . . . . . 10-15
Check and Service Engine
Soon Light . . . . . . . . . . . . . . . . . . 5-16
Compartment Overview . . . . . . . 10-6
Coolant . . . . . . . . . . . . . . . . . . . . . 10-19
Coolant Temperature Gauge . . . . . . . . . . . . . . . . . . . . . . 5-13
Coolant Temperature Warning Light . . . . . . . . . . . . . . . 5-22
Cooling System . . . . . . . . . . . . . 10-17
Cooling System Messages . . . 5-38
Drive Belt Routing . . . . . . . . . . . . 12-4
Exhaust . . . . . . . . . . . . . . . . . . . . . . 9-26
Heater . . . . . . . . . . . . . . . . . . . . . . . . 9-22
Oil Life System . . . . . . . . . . . . . 10-13
Oil Messages . . . . . . . . . . . . . . . . . 5-38
Overheated Protection
Operating Mode . . . . . . . . . . . 10-23
Overheating . . . . . . . . . . . . . . . . 10-21
Power Messages . . . . . . . . . . . . . 5-39
Pressure Light . . . . . . . . . . . . . . . . 5-23
Running While Parked . . . . . . . . 9-26
Starting . . . . . . . . . . . . . . . . . . . . . . . 9-18
Entry Lighting . . . . . . . . . . . . . . . . . . . 6-6
Equipment, Towing . . . . . . . . . . . . 9-67 Event Data Recorders . . . . . . . . 13-14
Exit Lighting . . . . . . . . . . . . . . . . . . . . 6-7
Extender, Safety Belt . . . . . . . . . . 3-19
Exterior Lamp Controls . . . . . . . . . 6-1
Exterior Lamps Off Reminder . . . 6-2
F
Features
Memory . . . . . . . . . . . . . . . . . . . . . . . . 1-8
Filter, Engine Air Cleaner . . . . . . . . . 10-15
Flash-to-Pass . . . . . . . . . . . . . . . . . . . 6-2
Flashers, Hazard Warning . . . . . . 6-4
Flat Tire . . . . . . . . . . . . . . . . . . . . . . 10-63 Changing . . . . . . . . . . . . . . . . . . . 10-72
FlexFuel E85 . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-60
Floor Mats . . . . . . . . . . . . . . . . . . . . 10-93
Fluid
Automatic Transmission . . . . 10-15
Brakes . . . . . . . . . . . . . . . . . . . . . . 10-26
Power Steering . . . . . . . . . . . . . 10-23
Washer . . . . . . . . . . . . . . . . . . . . . 10-24
Fog Lamps . . . . . . . . . . . . . . . . . . . . . 6-4
Folding Mirrors . . . . . . . . . . . . . . . . 2-19

Black plate (6,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
i-6 INDEX
Headlamps (cont'd)Flash-to-Pass . . . . . . . . . . . . . . . . . . 6-2
High Intensity Discharge
(HID) Lighting . . . . . . . . . . . . . 10-31
High-Beam On Light . . . . . . . . . . 5-25
High/Low Beam Changer . . . . . . 6-2
Lamps On Reminder . . . . . . . . . 5-25
Heated Steering Wheel . . . . . . . . . . . . . . . . 5-3
Heated and Ventilated Front Seats . . . . . . . . . . . . . . . . . . . . . . . . . 3-9
Heated Mirrors . . . . . . . . . . . . . . . . . 2-19
Heater Engine . . . . . . . . . . . . . . . . . . . . . . . . 9-22
High Voltage Devices and Wiring . . . . . . . . . . . . . . . . . . . . . . . 10-34
High-Beam On Light . . . . . . . . . . . 5-25
High-Speed Operation . . . . . . . . 10-51
Hill and Mountain Roads . . . . . . . . 9-7
Hill Start Assist (HSA) . . . . . . . . . 9-33
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . 10-5
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
How to Wear Safety Belts Properly . . . . . . . . . . . . . . . . . . . . . . 3-14I
Ignition Positions . . . . . . . . 9-15, 9-16
Ignition Transmission LockCheck . . . . . . . . . . . . . . . . . . . . . . . 10-29
Immobilizer . . . . . . . . . . . . . . . . . . . . 2-16
Indicator Vehicle Ahead . . . . . . . . . . . . . . . . 5-21
Infants and Young Children, Restraints . . . . . . . . . . . . . . . . . . . . 3-35
Information Energy . . . . . . . . . . . . . . . . . . . . . . . 5-27
Infotainment . . . . . . . . . . . . . . . . . . . . 7-1
Infotainment System . . . . . . . . . . 13-15
Instrument Cluster . . . . . . . . . . . . . . 5-8
Interior Rearview Mirrors . . . . . . . 2-19
Introduction . . . . . . . . . . . . . . . . . . . . . . . iii
J
Jump Starting . . . . . . . . . .10-78, 10-79
K
Key and Lock Messages . . . . . . . 5-39
Keyless Entry Remote (RKE) System . . . . . . . . 2-3
Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
L
Labeling, Tire Sidewall . . . . . . . . 10-44
Lamps Daytime Running (DRL) . . . . . . . 6-2
Dome . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Exterior Controls . . . . . . . . . . . . . . . 6-1
Exterior Lamps OffReminder . . . . . . . . . . . . . . . . . . . . 6-2
Fog . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
Headlamps, Front Turn Signal, and Parking
Lamps . . . . . . . . . . . . . . . . . . . . 10-32
License Plate . . . . . . . . . . . . . . . 10-33
Malfunction Indicator . . . . . . . . . 5-16
Messages . . . . . . . . . . . . . . . . . . . . 5-40