In this article we take a look at the fifth generation Audi A4 / S4 (B9/8W) (facelifted), produced from 2019 to the present. Here you will find the Audi A4 and S4 2020, 2021, 2022 fuse box outline, information on the location of the fuse boxes in the car and the allocation of each fuse (fuse layout).
Fuse Box Location
Driver’s/front passenger’s footwell
The fuses are located in the footwell under the foot rest (left-hand drive vehicle) or behind the cover (right-hand drive vehicle).
Instrument panel
Additional fuses are located on the front side of the cockpit (driver’s side).
Luggage Compartment
The fuses are located under the left cover in the luggage compartment.
Fuse Box Diagrams
Driver’s/front passenger’s footwell
LHD
RHD
Assignment of the fuses in the front passenger footwell
| № | Equipment |
|---|---|
| Panel A (brown) | |
| 1 | Catalytic converter heating |
| 2 | Engine components |
| 3 | Exhaust doors, fuel injectors, air intake, motor heating |
| 4 | Vacuum pump, hot water pump, NOx sensor, particulate sensor, biodiesel sensor, exhaust doors |
| 5 | Brake light sensor |
| 6 | Engine valves, camshaft adjustment |
| 7 | Heated oxygen sensors, mass airflow sensor, water pump |
| 8 | Water pump, high pressure pump, high pressure regulator valve, temperature valve, engine mount |
| 9 | 2020: Hot water pump, engine relay 2021-2022: Hot water pump, motor relay, 48 V starter generator, 48 V water pump |
| 10 | Oil pressure sensor, oil temperature sensor |
| 11 | Clutch position sensor, 48 V starter generator, water pump, 12V starter generator |
| 12 | Engine valves, engine mount |
| 13 | Engine cooling |
| 14 | Fuel injectors, drive system control module |
| 15 | Ignition coils, heated oxygen sensors |
| 16 | Fuel pump |
| Panel B (red) | |
| 1 | Anti-theft alarm system |
| 2 | Drive system control module |
| 3 | Left front seat electronics, lumbar support, massaging seat |
| 4 | Automatic transmission selector lever |
| 5 | Horn |
| 6 | Parking brake |
| 7 | Diagnostic interface (Gateway control module) |
| 8 | Roof electronics control module |
| 9 | Emergency call and communication control module |
| 10 | Airbag control module |
| 11 | Electronic Stabilization Control (ESC), Anti-Lock Braking System (ABS) |
| 12 | Diagnostic connection, light/rain sensor |
| 13 | Climate control system |
| 14 | Right front door control module |
| 15 | Climate control system compressor |
| 16 | 2021-2022: Brake system pressure reservoir |
| Panel C (black) | |
| 1 | Front seat heating |
| 2 | Windshield wipers |
| 3 | Left headlight electronics |
| 4 | Panoramic glass roof / sliding/tilting sunroof |
| 5 | Left front door control module |
| 6 | 12 volt socket |
| 7 | Right rear door control module, right rear power window |
| 8 | All wheel drive (AWD) control module |
| 9 | Right headlight electronics |
| 10 | Windshield washer system/headlight washer system control module |
| n | Left rear door control module, left rear power window |
| 12 | Parking heater |
| Panel D (black) | |
| 1 | Front seat electronic, seat ventilation, rearview mirror, rear climate control system control panel, windshield heating, diagnostic connection |
| 2 | Diagnostic interface, vehicle electrical system control module |
| 3 | Sound generator |
| 4 | Clutch position sensor |
| 5 | Engine start, emergency shut-off |
| 6 | Diagnostic connection, traffic information antenna (TMC) |
| 7 | USB connection |
| 8 | Garage door opener |
| 9 | Audi adaptive cruise control, adaptive distance regulation |
| 11 | Front camera |
| 12 | Right headlight |
| 13 | Left headlight |
| 14 | Transmission fluid cooling |
| 15 | 2020: Alarm and hands-free calling system |
| Panel E (red) | |
| 1 | Ignition coils |
| 2 | Climate control system compressor |
| 5 | Left headlight |
| 6 | Automatic transmission |
| 7 | Instrument panel |
| 8 | Climate control system blower |
| 9 | Right headlight |
| 10 | Dynamic steering |
| 11 | Engine start |
Instrument panel
Assignment of the fuses in the driver’s side of the cockpit
| № | Equipment |
|---|---|
| 1 | Convenience access and start authorization control module (NFC) |
| 2 | Audi phone box, USB connection |
| 4 | Head-up display |
| 5 | Audi music interface, USB connection |
| 6 | Front climate control system control panel |
| 7 | Steering column lock |
| 8 | Center display |
| 9 | Instrument cluster |
| 10 | Volume control |
| 11 | Light switch, switch module |
| 12 | Steering column electronics |
| 13 | 2020: Particulate matter sensor for climate control system |
| 14 | Infotainment system |
| 16 | 2020: Steering wheel heating 2021-2022: Steering column electronics, steering wheel heating |
Luggage Compartment
Assignment of the fuses in the trunk
| № | Equipment |
|---|---|
| Panel A (black) | |
| 2 | Windshield defroster |
| 3 | Windshield defroster |
| 5 | Suspension control |
| 6 | Automatic transmission |
| 7 | Rear window defogger |
| 8 | Rear seat heating |
| 9 | Left tail lights |
| 10 | Airbag, driver’s side safety belt tensioner control module |
| 11 | Luggage compartment lid lock, fuel filler door lock, convenience system control module |
| 12 | Luggage compartment lid |
| Panel B (red) | |
| 6 | 2020: Battery power interrupt 2021-2022: Electric compressor |
| Panel C (brown) | |
| 1 | 2021-2022: Exterior antenna |
| 2 | Audi phone box |
| 3 | Right front seat electronics, lumbar support, massaging seat |
| 4 | Side assist |
| 6 | Tire pressure monitoring system |
| 7 | Convenience access and start authorization control module (NFC) |
| 8 | Auxiliary heating, tank module |
| 10 | TV tuner, data exchange and telematics control module |
| 11 | Auxiliary battery control module |
| 12 | Garage door opener |
| 13 | Rearview camera, peripheral cameras |
| 14 | Right tail lights |
| 16 | Airbag, front passenger’s side safety belt tensioner control module |
| Panel E (red) | |
| 3 | Exhaust treatment |
| 5 | Right trailer hitch light |
| 7 | Trailer hitch |
| 8 | Left trailer hitch light |
| 9 | Trailer hitch socket |
| 10 | All wheel drive control module, sport differential |
| 11 | Exhaust treatment |
