Jonathan Yarden Jan 30, 2021 · 5 min. read
In this article you will find a description of fuses and relays Buick,
with photos of block diagrams and their locations.
Highlighted the cigarette lighter fuse (as the most popular thing people look for).
Get tips on blown fuses, replacing a fuse, and more.
Year of production: 2018
Engine Compartment Fuse Block
Mini Fuses | Usage |
1 | Sunroof |
2 | Exterior rearview mirror switch/Driver side power window/ Rain sensor/ Universal garage door opener |
3 | Canister vent solenoid |
4 | — |
5 | Electronic brake control module valve |
6 | Intelligent battery sensor |
7 | Electric steering column lock |
8 | Transmission control module/FICM |
9 | Automatic occupancy sensing module |
10 | Headlamp leveling switch/Headlamp leveling motor/Rear vision camera/ Interior rearview mirror |
11 | Rear wiper |
12 | Rear window defogger |
13 | Power lumbar switch |
14 | Exterior rearview mirror heater |
15 | Fuel system control module battery |
16 | Heated seat module/ Memory module |
17 | TIM DC DC converter/Fuel system control module RC/ Compass module |
18 | Engine control module RC/ Transmission control module RC/ FICM RC |
19 | Fuel pump |
20 | — |
21 | Fan relay (auxiliary BEC) |
22 | — |
23 | Ignition coil/ Injector coil |
24 | Washer pump |
25 | Automatic |
26 | EMS Var 1 |
27 | –/Auxiliary heater pump |
28 | –/Engine control module powertrain/ Ignition 3 |
29 | Engine control module powertrain/ Ignition 1/Ignition 2 |
30 | EMS Var 2 |
31 | Left high-beam headlamp |
32 | Right high-beam headlamp |
33 | Engine control module battery |
34 | Horn |
35 | A/C clutch |
36 | Front fog lamps |
J-Case Fuses | Usage |
1 | Electronic brake control module pump |
2 | Front wipe |
3 | Linear power module blower |
4 | IEC RC |
5 | — |
7 | –/Starter solenoid |
8 | Cooling fan low – mid |
9 | Cooling fan – high |
10 | EVP |
11 | Starter solenoid/ Starter pinion |
U-Micro Relays | Usage |
2 | Fuel pump |
4 | –/Auxiliary heater pump |
HC-Micro Relays | Usage |
7 | Starter/Starter pinion |
10 | Starter solenoid |
Mini Relays | Usage |
1 | Run/Crank |
3 | Cooling fan – mid |
5 | Powertrain relay |
8 | Cooling fan – low |
HC-Mini Relays | Usage |
6 | Cooling fan – high |
Auxiliary Fuse Block
Relays | Usage |
RLY01 | Electric vacuum pump |
RLY02 | Cooling fan control 1 |
RLY03 | Cooling fan control 2 |
RLY04 | N/A |
Instrument Panel Fuse Block
The instrument panel fuse block is on the underside of the driver side instrument panel.
Fuses | Usage |
F1 | Body control module 1 |
F2 | Body control module 2 |
F3 | Body control module 3 |
F4 | Body control module 4 |
F5 | Body control module 5 |
F6 | Body control module 6 |
F7 | Body control module 7 |
F8 | Body control module 8 |
F9 | Discrete logic ignition switch |
F10 | Sensing diagnostic module battery |
F11 | Data link connector |
F12 | HVAC module/ICS |
F13 | Liftgate relay |
F14 | Central gate moduleF15 |
F15 | Lane departure warning/GENTEX |
F16 | Adaptive forward lighting module |
F17 | Electrical steering column lock |
F18 | Parking assist module/Side blind zone alert |
F19 | Body control module/Regulated voltage control |
F20 | Clock spring |
F21 | A/C/Accessory power outlet/PRNDL |
F22 | Auxiliary power outlet/DC center |
F23 | HVAC module/ICS |
F24 | — |
F25 | OnStar module/ Eraglonass |
F26 | Heated steering wheel |
F27 | Instrument panel cluster/Auxiliary heater/Auxiliary virtual image display |
F28 | Trailer feed 2 |
F29 | Infotainment system |
F30 | DC/DC 400W |
F31 | Instrument panel cluster module battery |
F32 | Silver box audio module/Navigation |
F33 | Trailer feed 1 |
F34 | Passive entry/ Passive start |
Midi Fuses | Usage |
M01 | Positive temperature coefficient |
S/B Fuses | Usage |
S/B01 | Passenger power seat |
S/B02 | — |
S/B03 | Front power windows |
S/B04 | Rear power windows |
S/B05 | Logistic mode relay |
S/B06 | Driver power seat |
S/B07 | — |
S/B08 | Trailer interface module |
Circuit Breaker | Usage |
CB1 | — |
Relay | Usage |
RLY01 | Accessory/Retained accessory power |
RLY02 | Liftgate |
RLY03 | — |
RLY04 | — |
RLY05 | Logistic mode |
Rear Compartment Fuse Block
The rear compartment fuse block is behind a cover on the driver side of the rear compartment.
Fuses | Usage |
F1 | Amplifier audio |
F2 | Rear drive control module |
F3 | — |
F4 | — |
F5 | — |
F6 | — |
F7 | — |
F8 | — |
F9 | — |
F10 | — |
F11 | — |
F12 | — |
F13 | — |
F14 | — |
F15 | — |
F16 | — |
F17 | — |
S/B Fuses | Usage |
S/B01 | DC-DC transformer 400W |
S/B02 | DC-DC transformer 400W |
S/B03 | DC/AC inverter module |
S/B04 | — |
S/B05 | — |
Relays | Usage |
RLY01 | — |
RLY02 | — |
RLY03 | — |
RLY04 | — |
RLY05 | — |
Circuit Breaker | Usage |
CB1 | — |
WARNING: Terminal and harness assignments for individual connectors will vary depending on vehicle equipment level, model, and market.
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