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.
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.
The fuse box itself will look something like this.
Diagram
Assignment
Circuit breakers
| F1 | Left window |
| F2 | Right window |
| F3 | Not used |
| F4 | HVAC blower |
| F5 | Battery 2 |
| F6 | Electric steering column |
| F7 | Not used |
| F8 | Battery 3 |
| F9 | Engine control module/ Battery |
| F10 | Body control module 2 On/Off |
| F11 | Not used |
| F12 | Not used |
| F13 | Not used |
| F14 | Not used |
| F15 | Transmission control module On/Off |
| F16 | Amplifier |
| F17 | Not used |
| F18 | Battery 7 |
| F19 | Not used |
| F20 | Battery 1 |
| F21 | Battery 4 |
| F22 | Battery 6 |
| F23 | Electric steering column lock |
| F24 | Sensing and diagnostic module or Airbag sensing diagnostic module/ Passenger sensing module |
| F25 | Diagnostic link |
| F26 | Not used |
| F27 | AC DC inverter |
| F28 | Not used |
| F29 | Body control module 8 |
| F30 | Overhead console |
| F31 | Steering wheel control |
| F32 | Not used |
| F33 | HVAC |
| F34 | Center gateway module |
| F35 | Integrated chassis control module |
| F36 | Charger |
| F37 | Auxiliary power outlet/ Cigar lighter |
| F38 | OnStar |
| F39 | Monitor |
| F40 | Object detection |
| F41 | Body control module 1 On/Off |
| F42 | Radio |
| F43 | Circuit breaker 1 / Rear accessory power outlet |
| F44 | Circuit 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.
Relays
| K1 | Not used |
| K2 | Retained power of the accessory |
| K3 | Not used |
| K4 | Not used |
| K5 | Logistics |
Engine compartment
Under the hood, in the engine compartment on the right side, the main block with fuses and relays is installed.
Diagram
Designation
| 1 | Not used |
| 2 | Not used |
| 3 | ABS pump |
| 5 | AC DC inverter |
| 6 | Rear closure |
| 7 | Left corner lamp |
| 8 | Power windows/ Rearview mirror/ Power seats |
| 9 | Engine boost |
| 10 | Semi-active damping system – Airbag sensing diagnostic module/ Passenger sensing module – eAssist |
| 11 | DC DC Battery 1 |
| 12 | Rear window defogger |
| 13 | Heated mirrors |
| 14 | Not used |
| 15 | Passive entry/ Passive start |
| 16 | Front wipers |
| 17 | Passenger power seat |
| 18 | ABS valve |
| 19 | Driver power sea |
| 21 | Sunroof |
| 22 | Right corner lamp |
| 23 | Auto headlamp leveling |
| 24 | Not used |
| 26 | Transmission control module/ Ignition |
| 27 | Instrument panel/ Ignition |
| 28 | Electronic precision shift/ Ignition |
| 29 | Rear vision camera/ Ventilation |
| 30 | Malfunction indicator lamp/ Shift solenoid |
| 32 | Canister vent solenoid |
| 33 | Front heated seats |
| 34 | Rear heated seat/ Vehicle body safety module/Energy storage system fan or BSM (eAssist)/ Fan control module/ Damping control module (SADS) |
| 35 | Fog lamps |
| 36 | Fuel module |
| 38 | Not used |
| 39 | Not used |
| 40 | Steering columnn lock |
| 41 | Not used |
| 43 | Heated steering wheel |
| 44 | Headlamp leveling/ Rear seat ventilation |
| 45 | Not used |
| 46 | Engine control module/ Ignition |
| 47 | Not used |
| 48 | Engine boost/ Left cooling fan |
| 49 | DC DC battery 2/ AWD |
| 50 | Not used |
| 51 | Not used |
| 52 | Not used |
| 53 | Not used |
| 54 | Not used |
| 55 | Not used |
| 56 | Not used |
| 57 | Transmission auxiliary pump |
| 58 | TRCM |
| 59 | High-beam headlamps |
| 60 | Cooling fan |
| 61 | Not used |
| 62 | Not used |
| 63 | Not used |
| 65 | A/C HEV |
| 67 | Not used |
| 68 | Not used |
| 69 | Right HID low-beam headlamps |
| 70 | Left HID low-beam headlamps |
| 72 | Starter pinion |
| 74 | Starter motor |
| 75 | Engine control module |
| 76 | Powertrain – off engine |
| 77 | Not used |
| 78 | Horn |
| 79 | Washer pump |
| 81 | Transmission control module/ Engine control module |
| 82 | Not used |
| 83 | Ignition coils |
| 84 | Powertrain – on engine or Coil |
| 85 | Engine control module switch 2 |
| 86 | Engine control module switch 1 |
| 87 | SAI reaction pump |
| 88 | Aeroshutter |
| 89 | Headlamp washer |
| 91 | Not used |
| 92 | TPIM motor generator unit pump |
| 93 | Headlamp leveling |
| 95 | SAI reaction solenoid |
| 96 | Fuel heater |
| 97 | Not used |
| 99 | Coolant pump |
| Relays | |
| 4 | AC DC inverter |
| 20 | Rear defogger |
| 25 | Front wiper control |
| 31 | Run/Crank |
| 37 | Front wiper speed |
| 42 | Transmission auxiliary pump |
| 64 | A/C control |
| 66 | Powertrain |
| 71 | HID low-beam headlamps |
| 73 | Starter motor |
| 80 | Starter pinion |
| 90 | SAI reaction solenoid |
| 94 | Headlamp washer |
| 98 | SAI reaction pump |
Luggage compartment
Another fuse and relay box is located in the luggage compartment on the left side behind the protective cover.
Diagram
Allocation
| 1 | Empty |
| 2 | Empty |
| 3 | Trailer Interface Module |
| 4 | Empty |
| 5 | Keyless trunk door sensor |
| 6 | Empty |
| 7 | Empty |
| 8 | Electric rear door |
| 9 | Empty |
| 10 | Empty |
| 11 | Trailed socket |
| 12 | Heated front left seat |
| 13 | Heated front right seat |
| 14 | Empty |
| 15 | Heated rear seats 1 |
| 16 | Heated rear seats 2 |
| 17 | Empty |
| 18 | Trailed socket |
| 19 | Empty |
| 20 | Empty |
| 21 | Empty |
| 22 | Electric rear door |
if you found a mistake or have something to add, write in the comments.