Buick LaCrosse (2017 – 2019) Fuse Box Diagrams & Location User Guide
This blog covers the 2017–2019 Buick LaCrosse third generation. Fuse box diagrams for each model year, fuse panel locations, and fuse and relay component functions are included.
Fuse Box Locations
Passenger Compartment Fuse Box
It is located in the driver side instrument panel, behind the cover.
Engine Compartment Fuse Box
Passenger Compartment Fuse Box
Buick LaCrosse (2017 and 2018)
| No | Description |
|---|---|
| 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 | 2017: Sensing and diagnostic module 2018: 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 | 2017: Circuit breaker 1 2018: Rear accessory power outlet |
| F44 | 2017: Circuit breaker 2
2018: Front accessory power outlet |
| Relays | |
| K1 | Not used |
| K2 | Retained accessory power |
| K3 | Not used |
| K4 | Not used |
| K5 | Logistics |
Buick LaCrosse (2019)
| No | Usage |
|---|---|
| F1 | Left window |
| F2 | Right window |
| F3 | – |
| F4 | Heating ventilation & air conditioning blower motor |
| F5 | Body control module 2 |
| F6 | Electric steering column |
| F7 | – |
| F8 | Body control module 3 |
| F9 | Engine control module / Battery |
| F10 | Body control module 2 (stop/start) |
| F11 | – |
| F12 | – |
| F13 | – |
| F14 | – |
| F15 | Transmission control module (stop/start) |
| F16 | Amplifier |
| F17 | – |
| F18 | Body control module 7 |
| F19 | – |
| F20 | Body control module 1 |
| F21 | Body control module 4 |
| F22 | Body control module 6 |
| F23 | Electric steering column lock |
| F24 | Airbag sensing diagnostic module / Passenger sensing module |
| F25 | Data link connector |
| F26 | – |
| F27 | AC DC inverter |
| F28 | HID headlamps |
| F29 | Body control module 8 |
| F30 | Overhead console |
| F31 | Steering wheel control |
| F32 | – |
| F33 | Heating, ventilation & air conditioning |
| F34 | Communication gateway module |
| F35 | Integrated chassis control module |
| F36 | Charger |
| F37 | Auxiliary power outlet / Cigar lighter |
| F38 | OnStar |
| F39 | Display |
| F40 | Obstacle detection |
| F41 | Body control module 1 (stop/start) |
| F42 | Radio |
| F43 | Rear accessory power outlet |
| F44 | Front accessory power outlet |
| Relay No. | Usage |
|---|---|
| K1 | – |
| K2 | Retained accessory power |
| K3 | – |
| K4 | – |
| K5 | Logistics |
Engine Compartment Fuse Box
Buick LaCrosse (2017 and 2018)
| № | Description |
|---|---|
| 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 | 2017: Semi-active damping system 2018: 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 | 2017: Rear heated seat/ Vehicle body safety module/Energy storage system fan
2018: 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 | 2017: Powertrain – on engine
2018: 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 |
Buick LaCrosse (2019)
| Fuse No. | Usage |
|---|---|
| 1 | – |
| 2 | – |
| 3 | Antilock brake system pump |
| 5 | – |
| 6 | Rear closure |
| 7 | Left corner lamp |
| 8 | Power windows / Rearview mirror / Power seats |
| 9 | Electric brake boost / Pedestrian alert |
| 10 | Airbag sensing diagnostic module / Passenger sensing module – eAssist |
| 11 | DC DC Battery 1 |
| 12 | Rear window defogger |
| 13 | Heated mirrors |
| 14 | – |
| 15 | Passive entry / Passive start |
| 16 | Front wipers |
| 17 | Passenger power seat |
| 18 | Antilock brake system valve |
| 19 | Driver power seat |
| 21 | Sunroof |
| 22 | Right corner lamp |
| 23 | Auto headlamp leveling |
| 24 | – |
| 26 | Transmission control module / Ignition |
| 27 | Instrument panel / Ignition |
| 28 | – |
| 29 | Rear vision camera / Ventilated seats |
| 30 | Malfunction indicator lamp / Shift solenoid |
| 32 | Canister vent solenoid |
| 33 | Front heated seats |
| 34 | Battery system manager / Fan control module / Rear drive control module / Damping control module |
| 35 | Fog lamps |
| 36 | Fuel module |
| 38 | – |
| 39 | – |
| 40 | Steering column lock |
| 41 | – |
| 43 | Heated steering wheel |
| 44 | Headlamp leveling / Rear seat ventilation |
| 45 | – |
| 46 | Engine control module / Ignition |
| 47 | – |
| 48 | Electric brake boost / Left cooling fan |
| 49 | DC DC battery 2 / Rear drive control module |
| 50 | – |
| 51 | – |
| 52 | – |
| 53 | – |
| 54 | – |
| 55 | – |
| 56 | – |
| 57 | Transmission auxiliary pump |
| 58 | Transmission range control module |
| 59 | High-beam headlamps |
| 60 | Cooling fan |
| 61 | – |
| 62 | – |
| 63 | – |
| 65 | Air conditioning (HEV) |
| 67 | – |
| 68 | – |
| 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 | – |
| 78 | Horn |
| 79 | Washer pump |
| 81 | Transmission control module / Engine control module |
| 82 | – |
| 83 | Ignition coil – odd |
| 84 | Ignition coil – even |
| 85 | Shunt |
| 86 | Shunt |
| 87 | – |
| 88 | Aeroshutter |
| 89 | Headlamp washer |
| 91 | – |
| 92 | Traction power inverter module / Motor generator unit coolant motor |
| 93 | Headlamp leveling |
| 95 | – |
| 96 | – |
| 97 | – |
| 99 | Coolant pump |
| Relay No. | Usage |
|---|---|
| 4 | – |
| 20 | Rear defogger |
| 25 | Front wiper control |
| 31 | Run/Crank |
| 37 | Front wiper speed |
| 42 | Transmission auxiliary pump |
| 64 | Air conditioning control |
| 66 | Powertrain |
| 71 | HID low-beam headlamps |
| 73 | Starter motor |
| 80 | Starter pinion |
| 90 | – |
| 94 | Headlamp washer |
| 98 | – |