Production of the Audi 100 C4   in the 45 body style began in late 1990. This model was produced in 1991, 1992, 1993, and 1994. Audi then removed the number “100” from the model name, changed the car’s name to the Audi A6, and continued production through 1995, 1996, and 1997. This series was later replaced by a completely new version and design of the Audi A6. This material contains information about fuses and relays for the Audi A100 C4 and  
Audi A6 C4   from 1990-1997.

Fuse box inside

1. Additional relay and fuse board no. 1;
2. Fuse and relay mounting block (Audi 100), fuse mounting block (Audi A6);
3. Terminal block no. 1;
4. Central switchboard with relay box;
5. Additional mounting block no. 2;
6. Terminal block no. 2;
7. ignition system unit;
8. Additional mounting block no. 3;
9. Terminal block no. 3.

Depending on the vehicle’s configuration and model year, these diagrams may vary. Please proceed with caution.

Engine compartment fuse box – assignment

Additional fee – No. 1

Located in the engine compartment, you must remove the protective cover by sliding the latches to access it.

For Audi 100 C4 vehicles manufactured before 1994

Deciphering

NO.	function
1	Unused
2	Seat belt control relay, parking lights
3	Time delay relay for interior lighting
4	Unused
5	Headlight relay
6	Unused
7	Third fan speed relay
8	ABS relay
9	Unused
10	Power window relay
11	Power window relay
12	Rear window washer and wiper relay
13	Unused
14	Overcurrent relay for electric windows
15	Driver’s seat heating relay
16	Passenger seat heating relay
17	Unused

For A6 C4 vehicles manufactured between 1994 and 1997

Deciphering

NO.	function
1	Cooling fan control relay when engine is not running
2	Engine cooling fan relay
3	Third fan speed relay
4	Fog light relay
5	Unused
6	Relay for high-pressure washers
7	Daytime running light relay
8	Light switching relay
9	A/C clutch relay
10	Air conditioning module activation relay
11	Rear window wiper and washer relay
12	Unused
13	Speaker power relay
14	Lamp status monitoring unit
15	Lamp status monitoring unit
16	Servotronic control unit for power steering
17	Air conditioning relay
switch
A1	Automatic window closing
A2	Central locking
A3	Window regulator
A4	radio
A5	Seat heating
B1	Seat position memory
B2	Electric seats
B3	Heated door lock cylinders
B4	Unused
B5	Luke

For Audi 100 C4 vehicles manufactured before 1994

Deciphering

NO.	AND	function
1	15	Rear fog lights
2	15	Threat warning system
3	25	Horn, brake light
4	15	Clock,   cigarette lighter   , air conditioning, interior and trunk lighting, cruise control, radio
5	–	Unused
6	5	Lamps for the right rear light, parking light and side marker light
7	5	Left tail light, parking light and side marker light lamps
8	10	Right high beam, high beam indicator light
9		Left high beam
10	10	Low beam, right headlight
11	10	Left low beam
12	15	Differential lock system, reversing lights, cruise control, interior heating
13	15	fuel pump
14	5	License plate, instrument cluster, ashtray, air conditioning control unit, engine compartment and glove compartment lamps
15	25	Windshield wiper motor, turn signals, air conditioning, heated windshield washer nozzles, engine cooling fan temperature sensor
16	30	Rear window heating, rearview mirror heating
17	30	Air conditioning system (fan)
18	15	Rear window wiper
19	10	Central locking, anti-theft device, heated door locks
20	30	Seat heating
21	10	Diagnostic block
22	–	Unused
23	5	License plate lighting
24	–	Unused
25	30	Driver’s seat adjustment motors, driver’s seat position memory unit
26	5	Instrument cluster, power rearview mirrors, automatic steering, cruise control (if equipped)
27	10	ignition control unit
28	15	Fuel injection control unit
29	10	Heated oxygen sensor
30	–	Unused
31	–	Backups of backups
relay
1	Unused
2	2. Fan speed relay
3	1. Fan speed relay
4	Unused
5	Discharge relay
6	Unused
7	Horn relay
8	Automatic transmission and anti-theft device control relay
9	Unused
10	Fuel pump relay
11	Unused

For A6 C4 vehicles manufactured between 1994 and 1997

The fuses are located on the left side of the dashboard, under a cover that stands out from the rest of the background.

Program description

1. 10A – Right high beam and high beam indicator lamp
2. 10A – Left high beam
3. 10A – Right low beam 4. 10A – Left low beam 5. 5A – Right
sidelight 6. 5A – Left sidelight 7. 10A – License plate lights, glove box, engine compartment, temperature control panel, ashtray and dashboard 8. 15A – Clock, map reading lights, trunk light, cigarette lighter, interior lamps, sun visor lamps, trip computer, rearview mirror adjusters, programmable seat adjusters 9. 10A – Brake lights 10. 15A – Hazard warning flashers 11. 30A – Heating fan, air conditioning 12. 30A – Rear window and rearview mirror defroster 13. 25A – Windshield wipers, turn signals, radiator fans, washer heaters, transmission oil temperature sensor 14. 15A – Reversing light, windshield washer, cruise control, differential lock, multifunction sensor, speedometer sensor, water filter, automatic transmission 15. 5A – Dashboard, rear-view mirror, trip computer 16. 15A – Fog lights 17. 20A – Fuel pump, heating valve 18. 15A – Rear window wiper 19. 25A – Diagnostic system, horn, fan relay 20. 5A – Cruise control, automatic transmission 21. 15A – ABS

Central fuse box

Still only for Audi A6 C4 vehicles from 1994-1997

Description

NO.	function
1	Discharge relay
2	Horn relay
3	Headlight washer relay
4	Central locking relay Tail light relay (manual gearbox) Automatic gearbox relay (part no.)
5	Relay interrupting the operation of the windshield wipers and washers
6	Fuel pump relay

Additional mounting block – No. 5

Description

NO.	function
1	Electric window lift control unit
2	Electric window lift control unit
3	Electric rearview mirror control. Automatic window closing.
4	ABS combi electric rearview mirror control unit
5	Gear shift lock control module.
6	Automatic transfer
7	Cooling fan fuse Electronic damping control module (fuse)
8	Fan (fuse)

Junction block 3 – No. 9

Description

NO.	function
1	Unused
2	Airbag warning light relay
3	Unused
4	Unused
5	Auxiliary air pump relay
6	Unused
7	Unused
8	Securing the additional exhaust manifold air pump