Buick LaCrosse 3G (2017 – 2023) fuse and relay

Buick LaCrosse 3rd generation was produced in 2017, 2018, 2019, 2020, 2021, 2022, 2023. During that time, the model was updated. In this post we will present a description of the fuses and relays of the Buick LaCrosse 3G, with fuse box diagrams, their locations and photo examples of execution. Let’s highlight the cigarette lighter fuse.

Buick LaCrosse 3G

The purpose of fuses and relays, as well as their number in blocks, may differ from those presented and depend on the year of manufacture, the level of electrical equipment and the region of delivery of your car.

Passenger compartment

Inside the car, the fuse and relay box is located on the left side at the bottom of the instrument panel, behind the protective cover. To access the unit, press on the sides of the cover and pull to release it from the dashboard. Next, pull it towards you.

Location 1

The fuse box itself will look something like this.

photo 1




Circuit breakers

F1Left window
F2Right window
F3Not used
F4HVAC blower
F5Battery 2
F6Electric steering column
F7Not used
F8Battery 3
F9Engine control module/ Battery
F10Body control module 2 On/Off
F11Not used
F12Not used
F13Not used
F14Not used
F15Transmission control module On/Off
F17Not used
F18Battery 7
F19Not used
F20Battery 1
F21Battery 4
F22Battery 6
F23Electric steering column lock
F24Sensing and diagnostic module or Airbag sensing diagnostic module/ Passenger sensing module
F25Diagnostic link
F26Not used
F27AC DC inverter
F28Not used
F29Body control module 8
F30Overhead console
F31Steering wheel control
F32Not used
F34Center gateway module
F35Integrated chassis control module
F37Auxiliary power outlet/ Cigar lighter
F40Object detection
F41Body control module 1 On/Off
F43Circuit breaker 1 / Rear accessory power outlet
F44Circuit breaker 2 / Front accessory power outlet

The fuses responsible for the cigar lighter and power outlets in the Buick LaCrosse are identified as follows: Fuse No. F37 (Auxiliary power outlet/Cigar lighter), Fuse No. 43 (Rear accessory power outlet), and Fuse No. 44 (Front accessory power outlet), all located within the Passenger compartment fuse box.


K1Not used
K2Retained power of the accessory
K3Not used
K4Not used

Engine compartment

Under the hood, in the engine compartment on the right side, the main block with fuses and relays is installed.

Insignia B fuse box


Diagram 2


1Not used
2Not used
3ABS pump
5AC DC inverter
6Rear closure
7Left corner lamp
8Power windows/ Rearview mirror/ Power seats
9Engine boost
10Semi-active damping system – Airbag sensing diagnostic module/ Passenger sensing module – eAssist
11DC DC Battery 1
12Rear window defogger
13Heated mirrors
14Not used
15Passive entry/ Passive start
16Front wipers
17Passenger power seat
18ABS valve
19Driver power sea
22Right corner lamp
23Auto headlamp leveling
24Not used
26Transmission control module/ Ignition
27Instrument panel/ Ignition
28Electronic precision shift/ Ignition
29Rear vision camera/ Ventilation
30Malfunction indicator lamp/ Shift solenoid
32Canister vent solenoid
33Front heated seats
34Rear heated seat/ Vehicle body safety module/Energy storage system fan or BSM (eAssist)/ Fan control module/ Damping control module (SADS)
35Fog lamps
36Fuel module
38Not used
39Not used
40Steering columnn lock
41Not used
43Heated steering wheel
44Headlamp leveling/ Rear seat ventilation
45Not used
46Engine control module/ Ignition
47Not used
48Engine boost/ Left cooling fan
49DC DC battery 2/ AWD
50Not used
51Not used
52Not used
53Not used
54Not used
55Not used
56Not used
57Transmission auxiliary pump
59High-beam headlamps
60Cooling fan
61Not used
62Not used
63Not used
67Not used
68Not used
69Right HID low-beam headlamps
70Left HID low-beam headlamps
72Starter pinion
74Starter motor
75Engine control module
76Powertrain – off engine
77Not used
79Washer pump
81Transmission control module/ Engine control module
82Not used
83Ignition coils
84Powertrain – on engine or Coil
85Engine control module switch 2
86Engine control module switch 1
87SAI reaction pump
89Headlamp washer
91Not used
92TPIM motor generator unit pump
93Headlamp leveling
95SAI reaction solenoid
96Fuel heater
97Not used
99Coolant pump
4AC DC inverter
20Rear defogger
25Front wiper control
37Front wiper speed
42Transmission auxiliary pump
64A/C control
71HID low-beam headlamps
73Starter motor
80Starter pinion
90SAI reaction solenoid
94Headlamp washer
98SAI reaction pump

Luggage compartment

Another fuse and relay box is located in the luggage compartment on the left side behind the protective cover.

Location 3


Diagram 3


3Trailer Interface Module
5Keyless trunk door sensor
8Electric rear door
11Trailed socket
12Heated front left seat
13Heated front right seat
15Heated rear seats 1
16Heated rear seats 2
18Trailed socket
22Electric rear door


if you found a mistake or have something to add, write in the comments.

Leave a Reply

Your email address will not be published. Required fields are marked *