Audi A8 and S8 fuse box and relay Diagrams (1994-2002)

The Audi A8 and S8, produced between 1994 and 2002, are luxury sedans known for their innovative technology and high performance. Along with their luxurious features, these models also boast an advanced electrical system that includes a fuse box and relay. In this guide, we will provide an overview of the electrical components found in the Audi A8 and S8 models, as well as tips for troubleshooting common issues.

Fuse Box

The fuse box in the Audi A8 and S8 models is located on the driver’s side of the dashboard, behind a plastic cover. The fuse box contains various fuses that protect electrical components from damage caused by power surges and other electrical issues. In some cases, a blown fuse can cause a specific electrical component to malfunction or stop working altogether. If this happens, it’s important to consult the owner’s manual or a professional mechanic to determine which fuse needs to be replaced.

Relay

In addition to the fuse box, the Audi A8 and S8 also have a relay, which is an electrical component that helps control various systems throughout the car. The relay acts as a switch, turning components on and off as needed. If a relay fails, it can cause a variety of issues, such as a malfunctioning air conditioning system or a non-functioning power window. In some cases, a relay can be replaced easily by a skilled DIYer or a professional mechanic. However, it’s important to properly diagnose the issue before attempting any repairs to avoid damaging other electrical components.

MUST READ: DYI – How to Check Car Fuses?

(1994-2002) Audi A8 and S8 fuse box and relay with Diagram

Passenger Compartment Fuse Box

No.	A	Protected Component
1	5	Lamp Control Module, Left Parking Light, Left Front Side Marker Light, Instrument Cluster Combination Processor
2	5	Lamp Control Module, Right Parking Light, Right Front Side Marker Light, Tail Lights, Licence Plate Lights, Instrument Cluster Combination Processor
3	15	’97-’03: Right Headlamp (Low Beam), Lamp Control Module
	10	Right Headlamp (Low Beam), Lamp Control Module
4	15	’97-’03: Left Headlamp (Low Beam), Headlight Aiming System, Lamp Control Module
	10	Left Headlamp (Low Beam), Headlight Aiming System, Lamp Control Module
5	10	Left Headlamp (High Beam), Front/Rear Foglight Control Module
6	10	Right Headlamp (High Beam), High Beam Indicator Light
7	15	Emergency Flasher Switch
8	15	Horn
9	10	’00-’03: Data Link Connector
	5	’98-’99: Data Link Connector, Selector Lever Light Relay
	5	-’97: Instrument Cluster, Solar Cell Separation Relay
10	25	Windshield Wiper Washer Switch, Windshield Wiper Washer Intermittent Relay
11	10	Outside Mirrors
12	10	’00-’03: Heated Steering Wheel, Steering Wheel Control Module
	5	?: Shift Lock Relay
13	5	A/C Control Head, Cigarette Lighter, Fog Light Relay, Glove Compartment Light, Instrument Cluster, Instrument Cluster Combination Processor, Tail Lights, Ashtray Light, Rear Ashtray Light, Multifunction Transmission Range Switch, Automatic Transmission Console Light, Licence Plate Lights, Illumination For Storage Tray, Cup Holder & Coin Holder, Selector Lever Light Relay Protection Diode, Interior Lights System, Light Switch
14	5	First Speed Coolant Fan Control Relay, Second Speed Coolant Fan Control Relay, Third Speed Coolant Fan Control Relay, Air Quality Sensor (’98-’03)
15	15	Fog Light Switch, Rear Fog Light Switch, Fog Light Control Module
16	30	’97-’03: Rear Window Defogger Switch, Mirror Defogger, A/C Control Head (’00-’03)
	25	?: Rear Window Defogger Switch, Mirror Defogger
17	5	’00-’03: Steering Angle Sensor
	10	?: Back-Up Light
18	10	Emergency Flasher Switch
19	10	Stop Lamp Switch, Vacuum Pump Valve, Transmission Control Module
20	5	Washer Nozzle Heaters
21	15	Data Link Connector, Instrument Cluster, Lamp Control Module, Steering Wheel Control Module, Radio, Headlight Beam Adjustment Motors, Headlight Beam Adjustment Control Module, Parking Aid Control Module, Tire Pressure Monitoring Control Module, Air Bag Malfunction Indicator Lamp, ABS Malfunction Indicator Lamp, Traction Control Indicator Lamp
22	5	’00-’01: Telephone Transceiver, Radio
	10	-’98: Telephone Transceiver
23	15	-’01: Cigarette Lighter
24	10	’00-’03: A/ C Control Head, Instrument Cluster Combination Processor, Parking Aid Control Module, Solar Cell Separation Relay, Steering Wheel Control Module, Tire Pressure Monitoring Control Module
	5	’97-’99: Instrument Cluster Combination Processor
	5	?: A/ C Control Head
25	10	’00-’03: A/C Control Head
	15	-’99: A/C Control Head, Interior Temperature Sensor, Instrument Cluster, Solar Cell Separation Relay, Steering Wheel Control Module
26	10	’97-’03: Multifunction Transmission Range Switch, Shift Lock Solenoid
	5	?: Multifunction Transmission Range Switch, Shift Lock Solenoid, Cruise Control System
27	15	Coolant Pump, Heat Regulating Valves
28	10	’00-’03: A/C Clutch Relay
	15	-’97: Coolant Pump, Auxiliary Heater
29	5	’00-’03: Steering Wheel Control Module
	10	-’99: Steering Wheel Control Module
30	–	–
31	20	’00-’03: Fuel Pump
	15	-’99: Fuel Pump
32	30	’00-’03: Fuel Injectors, Ignition Coils, Valves No. 1 & 2 for Camshaft Adjustment (’01-’03)
	20	-?: Heated Oxygen Sensors Before TWC, EVAP Leak Detection Pump
33	20	Heated Oxygen Sensors Before TWC, EVAP Leak Detection Pump, Mass Air Flow Sensor
34	15	-’99: Heated Oxygen Sensors After TWC
35	5	’00-’03: Navigation Control Unit
	5	-?: Auxiliary Heater
36	10	’00-’03: Navigation Control Unit
	15	-?: Auxiliary Heater
37	–	–
38	5	’00-’03: Oil Level Thermal Sensor
39	25	’00-’03: ABS Control Module
	5	-’99: ABS Control Module
40	10	ABS Control Module, Anti-Slip Control Switch (with FWD), Brake Vacuum Vent Valve, ARS/ESP Switch, Stop Lamp Switch (Quattro)
41	10	Front Interior Light, Rear Reading Lights, Central Locking/Alarm System/Interior Light Delay Control Module, Central Locking SAFE Warning Light, Left Front Reading Light, Interior & Map/Reading Relay, Passenger Compartment Monitoring Switch, Make Up Mirror Lights, Door Warning Lights, Power Trunk Release, Power Rear Sunshade
42	10	Right & Left Power Windows Control Module, Mirror Adjustment Switch, Mirror Fold-Away Function Control Module, Memory Program Switch, Rear Headrest Adjustment Switch, Front Heated Seat Switches, Rear Heated Seat Switch, Front Seat Memory Switch
43	15	’00-’03: Luggage Compartment Release Switch, Right & Left Make Up Mirror Lights, Right & Left Make Up Mirror Lights Switch, Entry/Floor Light Relay, Interior Monitoring Sensors Control Module, Driver’s Side Interior Lock Switch, Mirror Memory Control Module, Memory Program Switch, Passengers Seat Memory Program Switch, Ultra Sound Sensors Control Module, Right Reading Light/Map Light, Left Reading Light, Interior Lights
	10	’99: Luggage Compartment Release Switch, Right & Left Make Up Mirror Lights, Entry/Floor Light Relay, Interior Monitoring Sensors Control Module, Driver’s Side Interior Lock Switch, Mirror Memory Control Module, Memory Program Switch, Rear Fog Light Switch
44	10	Central Locking/Alarm System/Interior Lights Delay Control Module, Rear Window Shade Switch, Automatic Dimmer Inside Mirror, Garage Door Control Module, Interior & Map/Reading Light Relay
45	15	Central Locking/Alarm System/Interior Lights Delay Control Module, Interior Monitoring Sensors Control Module, Driver’s Side Interior Lock Switch
46	20	Power Sunroof Control Module
47	15	Window Lockout Switch, Right & Left Heated Door Lock Control Module, Cigarette Lighter
48	10	-’97: Memory Program Switch, Mirror Memory Control Module
49	20	Steering Column/Belt Height Control Module, Steering Column Adjustment Switch
50	20	Front Heated Seat Switch, Rear Window Shade Control Module
51	60	-’00: Cooling Fan
	50	???
52	60	’01-’03: Cooling Fan

Passenger Compartment Relay Box No.1

No.	Relay
R1	’00-’03: Horn (J4)
	-’99: Load Reduction (J59)
R2	’00-’03: Load Reduction (J59)
	-’99: Horn (J4)
R3	-’99: Headlight Washer System (J39)
R4	’00-’03: Fuel Pump (J17)
	-’99: Staring Interlock (J207)
	-’99: Starter Inhibitor and Reversing Light (J226)
R5	-’99: Automatic Intermittent Wiper/Washer (J31)
R6	-’99: Fuel Pump (J17)

Passenger Compartment Relay Box No.2

No.	Relay
R1	Mirror Fold (J351)
R2	A/C Clutch (J44)
R3	Solar Cell Separation (J309)
	Selector Lever Light (J307)
	Selector Lever Illumination Diode (J443)
R4	Servotronic Control Module (J236)
R5	Interior and Map/Reading Light (J91)
	Selector Lever Lock Control Unit (J221)
R6	Wiper/Washer Intermittent (J31)
	Fog Light (J5)
R7	(R7+R12): Front/Rear Fog Light Control Module (J512)
	Daytime Running Lights Change-Over (J89)
	Staring Interlock (J89)
R8	Auxiliary Heater (J8)
R9	Bulb Monitoring Device (J123)
R10	Entry & Floor Light (J348)
R11	Wiper/Washer Intermittent (J31)
	Solar Cell Isolation (J309)
R12	(R7+R12): Front/Rear Fog Light Control Module (J512)
	Fresh Air Blower (J13)
R13	Automatic Sliding Sunroof Close (J356)

Passenger Compartment Relay Box No.3

No.	A	Protected Component
3	40	Blower Fan
4	–	–
5	–	–
6	–	–
7	–	–
Circuit Breaker
1	30	Power Seat (No.2)
2	30	Power Seat (Memory) (No.1)
Relay
R1	Starting Interlock (J207)
	Entry and Footwell Lighting (J348)
R2	–
R3	Daytime Running Lights (J90)
R4	Driving Lights (Litronic) (J336)

Passenger Compartment Relay Box No.4

No.	A	Protected Component
3	–	–
4	–	–
Circuit Breaker
1	30	Power Window (Rear)
2	30	Power Window (Front)
Relay
R1	Hazard Warning Light (J2)
	Turn Signal (J1)
R2	(R2+R5) Multi-Function Steering Wheel (J453)
	Second Speed Coolant Fan Control (J101)
	(R2+R5) Electric Windows and Sliding Sunroof (J139)
R3	ABS Return Flow Pump (J105)
	Horn (J4)
	Second Speed Coolant Fan Control (J101)
R4	Automatic Window Closing (J261)
R5	(R2+R5) Multi-Function Steering Wheel (J453)
	Coolant Fan Control Relay (First Speed) (J26)
	(R2+R5) Electric Windows and Sliding Sunroof (J139)
R6	ABS Solenoid Valve (J106)
	Load Reduction (J59)
	Coolant Fan Control Relay (First Speed) (J26)

Luggage Compartment Fuse Box

No.	A	Protected Component
1	20	Heated Seats, Right & Left Rear Seat Regulating Switch
2	25	ABS Valves
	20	Radio, Amplifier, Right & Left Rear Woofers, Power Antenna
3	5/15	Telephone
4	–	–
5	20	Power Seat
6	20	Trailer Tow
7	25	ABS Valve
	20	Radio
	15	Radio
8	–	–
9	–	–
10	20	Power Seat
11	50	ABS Control Module
	60	ABS Control Module
12	–	–
13	60	Auxiliary Heater
	60	Second Battery
14	–	–
15	–	–
16	–	–
Relay
R1	(4+9) Battery Isolation (J7)

Engine Compartment Fuse Box

No.	A	Protected Component
1	15	Transmission Control Module
2	15	EVAP Canister Purge Regulator Valve, Intake Change Over Valve, Fuel Injector Air Control Valve & EVAP Leak Detection Pump
	15	ECM & Fuel Injectors
3	15	ECM & Fuel Injectors
	20	EVAP Canister Purge Regulator Valve, Intake Manifold Tuning Valve No. 1, Intake Manifold Tuning Valve No. 2, Fuel Injector Air Control Valve & EVAP Leak Detection Pump, Secondary Air Injection, Electrohydraulic Engine Mounts, MAF Sensor, Camshaft Adjustment Valves, (Control Elements).
4	20	ECM & Ignition Coil Terminal No. 15
	5	ECM
5	15	Transmission Control Module
Relay
R1	Immobilizer (J341)
R2	Engine Control Module (J271)
	Secondary Air Injection Pump (J299)

In conclusion, the Audi A8 and S8 1994-2002 are luxurious vehicles that come equipped with advanced electrical components, including a fuse box and relay. While these components can provide reliable performance for years, they may require maintenance or repair from time to time. By understanding how these electrical systems work and troubleshooting common issues, Audi owners can enjoy their vehicles for years to come.