The Audi 80 and Audi 90 (B3) is produced between 1986-1991 and is the third generation of Audi’s popular mid-size car. It is available in both sedan and wagon versions and featured numerous improvements over its predecessor, including better handling, more comfortable interior, and improved fuel efficiency.
One of the most important aspects of the Audi 80 and Audi 90 (B3) is its electrical system. The car features a fuse box and relay, which are vital components for ensuring the proper function of various electrical systems within the vehicle. In this article, we will explore the Audi 80 and Audi 90 (B3) in more detail and look at how the fuse box and relay contribute to its performance.
Body
Design and Features
The Audi 80 and Audi 90 (B3) is designed with a sleek, aerodynamic profile that gave it a more modern look compared to its predecessors. The car featured a front-wheel-drive layout and is available with a range of engines, including both diesel and gasoline options. The interior of the car is also improved, with more comfortable seating and a modern dashboard design that incorporated numerous electronic features.
Electrical Components
The Audi 80 and Audi 90 (B3) featured a complex electrical system that is important for the proper function of various components, such as the headlights, radio, and air conditioning. The car’s fuse box and relay played a crucial role in this system. The fuse box is responsible for protecting various electrical circuits from damage due to overloading, while the relay helps to control the flow of electricity to various components.
One common issue with the fuse box and relay in the Audi 80 and Audi 90 (B3) is corrosion. This can cause electrical problems, such as dimming headlights or a malfunctioning radio. It is important to regularly check and clean the fuse box and relay to prevent such issues.
Maintenance and Repairs
Regular maintenance is key to keeping the Audi 80 and Audi 90 (B3) in good working order. This includes checking the fuse box and relay, as well as other electrical components, such as the alternator and battery. If any issues are detected, it is important to have them addressed promptly to avoid more serious problems down the line.
When it comes to repairs, it is important to use quality parts and work with a reputable mechanic who is familiar with the Audi 80 and Audi 90 (B3). This will help ensure that any repairs are done correctly and that the car remains safe and reliable.
(1986-1991) Audi 80 and Audi 90 (B3) fuse box and relay with Diagram
Engine compartment fuse box
| No. | Assignment/Designation | Amps |
| 1 | Fog lights, rear fog light | 15A |
| 2 | Emergency flashers | 15A |
| 3 | Horn, brake lights | 25A |
| 4 | Reading lights, luggage compartment, cigar lighter, interior lights, make-up mirror, Board Computer, radio, clock, auto climate control, alarm system | 15A |
| 5 | Radiator cooling fan | 30A |
| 6 | Side marker, park lights, right | 5A |
| 7 | Side marker, park lights, left | 5A |
| 8 | Hi-beam headlight, right, hi-beam indicator light | 10A |
| 9 | Hi-beam headlight, left | 10A |
| 10 | Low beam headlight, right | 10A |
| 11 | Low beam headlight, left | 10A |
| 12 | Instrument cluster, back-up lights, Auto-Check, cruise control, ABS, Board Computer, differential locks, electronic thermoswitch, throttle valve time control unit, radiator cooling fan after-run control unit | 15A |
| 13 | Fuel pump, warm-up regulator | 15A |
| 14 | Glove compartment, engine compartment, license plate lights | 5A |
| 15 | Windshield wipers, thermoswitch, radiator cooling fan, turn signals, A/C pressure switch | 25A |
| 16 | Rear window heat element, outside mirror heat element | 30A |
| 17 | Fresh air blower, A/C | 30A |
| 18 | Power mirrors, rear window wiper (Coupe) | 5A |
| 19 | Central locking system, heated lock system | 10A |
| 20 | Radiator cooling fan (step 1), radiator cool fan after-run | 30A |
| 21 | Diagnostic | 10A |
| 21 | Rear cigar lighter | 25A |
| 22 | – | – |
| 23 | Power seats with memory, power seat control unit | 30A |
| 24 | Engine control I | 10A |
| 25 | Heated seats | 30A |
| 26 | Daytime driving lights (Canada) | 5A |
| 27 | Engine Control I (from September 1987) | 10A |
| 28 | Engine control II | 15A |
| 29 | Spare fuses | 15A |
| Relay | ||
| I | Fog lights, J5 | |
| II | up to 1990: Radiator cooling tan (stage 2), J101 from 1990: – | |
| III | Radiator cooling fan after-run control unit, J138 | |
| IV | up to 1990: – from 1990: Headlight washer system, J39 | |
| V | Load reduction relay, J18 | |
| VI | up to 1990: A/C fresh air blower, J11 from 1990: Radiator cooling fan high speed relay, J101 | |
| VII | Horn, J4 | |
| VIII | Bridge between contact 36 and 38 for manual transmissions Auto transmission, J60 | |
| IX | Intermittent washer/wiper, J31 | |
| X | Fuel pump, J17 | |
| XI | Radiator cooling fan (stage 1), J26 | |
Auxiliary relay panel
| No. | Assignment/Designation |
| 1 | ABS system, J156 |
| 2 | Seat belt, radio, parking light warning, J152 |
| 3 | Interior light control unit, J140 |
| 4 | A/C clutch control unit, J153 |
| 5 | – |
| 6 | Dynamic oil pressure warning (without Auto-Check), J114 Lamp control unit, front (with Auto-Check), J123 |
| 7 | – |
| 8 | – |
| 9 | – |
| 10 | – |
| 11 | – |
| 12 | Circuit breaker (power seats with memory, power windows, power sunroof), S43 |
| 13 | Seat heater control unit, passenger. J132 |
| 14 | Seat heater control unit, driver, J131 |
| 15 | Sunroof relay, J139 Sunroof and power window control unit, J139 |
| 16 | Sunroof and power window control unit, J139 |
| 17 | Wire distributor adaptor, (optional equipment connector) |
| 18 | – |
Overall, the Audi 80 and Audi 90 (B3) is an important milestone in the evolution of Audi’s mid-size car. Its improved handling, modern design, and advanced electrical system set the stage for future generations of Audi vehicles. By understanding the importance of the fuse box and relay in this car, owners can better maintain and repair their vehicles, ensuring that they remain safe and reliable for years to come.
