Audi A3 (8P) | 2003-2007 | Fuse Box Diagrams and Locations

The pre-facelift second-generation Audi A3 and S3 (chassis code 8P), Audi’s premium compact car and its sporty performance variant, was produced from 2003 to 2007. Known for its modern design, improved technology, and versatility, this version of the A3 and S3 set the stage for Audi’s dominance in the luxury compact car market.

In this article, you will find fuse box diagrams for Audi A3 and S3 models produced in 2003, 2004, 2005, 2006, and 2007. These diagrams provide crucial details about the fuse layout and relay assignments, helping you troubleshoot and maintain the vehicle’s electrical systems efficiently.

What’s Included:

Fuse Box Diagrams: Clear and detailed visuals for quick identification of fuses.
Fuse Panel Locations: Step-by-step guidance on where to locate the fuse panels inside your car.
Fuse Assignments: A breakdown of the function of each fuse and relay to aid in troubleshooting and repairs.

Whether you’re an Audi enthusiast tackling DIY repairs or a professional technician, this guide is an essential resource for maintaining your Audi A3/S3 (8P). From resolving electrical issues to replacing a faulty fuse, this comprehensive reference ensures your vehicle remains in optimal condition.

Keep your Audi A3/S3 (8P) running smoothly with this detailed fuse box guide!

What’s Included

Instrument Panel Fuse Box

Fuse Box Location

The fuses are behind a cover on the driver’s side. Carefully pry the fuse cover off the instrument panel using the ignition key or a screwdriver.

Location of the fuses in the passenger compartment: Audi A3 (2004, 2005, 2006, 2007)

Fuse Box Diagram

Assignment of the fuses in the instrument panel

№	Amps	Function/component
1	10A	Light switch Fuel pump relay Engine control unit Motronic control unit Diesel direct injection system control unit Fuel pump control unit 16-pin connector (diagnostic connector)
2	5A	ABS control unit Brake light switch Brake pedal switch
3	10A	2003-2005: Power steering control unit
3	5A	2006-2007: Airbag control unit Front passenger side airbag deactivated warning lamp
4	5A	Tyre pressure monitor button TCS and ESP button Reversing light switch High pressure sender Air quality sensor Oil level and oil temperature sender Heater control unit Heated rear left seat control unit Heated rear right seat control unit Driver seat heating control unit Front passenger seat heating control unit
5	5A/10A	2003-2005: Airbag control unit Seat occupied recognition control unit Clutch position sender Brake light switch Brake pedal switch 2006-2007: Headlight range control, control unit Headlight range control regulator Left headlight range control motor Right headlight range control motor
6	5A	Function selection switch 2 Selector lever Tiptronic switch Power steering control unit Data bus diagnostic interface Mechatronic unit for dual clutch gearbox Trailer detector control unit
7	5A	2003-2005: Heater control unit Headlight range control, control unit Heated rear left seat switch with regulator Heated rear right seat switch with regulator 2006-2007: Garage door operating unit Trailer detector control unit Navigation system with CD drive control unit Navigation operating electronics control unit Parking aid control unit Garage door operation control unit Automatic anti-dazzle interior mirror
8	10A	2003-2005: Garage door operating unit Navigation system with CD drive control unit Parking aid control unit Garage door operation control unit Automatic anti-dazzle interior mirror 2006-2007: Trailer socket
9	5A	2003-2005: Four-wheel drive control unit
10	5A	2003-2005: Selector lever Tiptronic switch 2006-2007: Seat occupied recognition control unit
11	5A/10A	2003-2005: Trailer socket 2006-2007: Power output module for right headlight
12	10A	Driver door control unit Front passenger door control unit
13	10A	Brake light switch (brake lights) 16-pin connector (diagnostic connector)
14	5A	Automatic gearbox control unit
15	10A	Onboard supply control unit
16	10A	Rain and light detector sensor Heater control unit Climatronic control unit Remote control receiver for auxiliary heater
17	5A	Convenience system central control unit -J393-
18	5A	Selector lever Tiptronic switch Parking aid control unit ABS control unit (2003-2005)
19	10A	Rear left door control unit Rear right door control unit
20	5A	2006-2007: ABS control unit
21	–	–
22	40A	Fresh air blower control unit
23	20A/30A	2003-2005: Headlight washer system relay Headlight washer system pump 2006-2007: Driver side window regulator motor
24	20A	Cigarette lighter 12V socket
25	30A	Heated rear window
26	20A	Electric socket
27	15A	Electric fuel pump 2 relay Fuel pump control unit Fuel pump relay
28	30A	2006-2007: Rear left window regulator motor Rear right window regulator motor
29	10A	2003-2005: Motronic control unit Diesel direct injection system control unit Simos control unit Fuel pump control unit Front passenger side airbag deactivated warning lamp 2006-2007: Air mass meter Heater element for crankcase breather
30	10A	2006-2007: Injector, cylinder 1~6
31	5A	2003-2005: Reversing light switch Mechatronic unit for dual clutch gearbox 2006-2007: Four-wheel drive control unit
31	20A	2006-2007: Vacuum pump relay
32	30A	2006-2007: Headlight washer system pump Headlight washer system relay
33	25A	Sliding sunroof adjustment control unit
34	20A	Heated rear left seat control unit Heated rear right seat control unit
35	5A	Interior monitoring sensor Vehicle inclination sender Alarm horn
36	10A	Driver seat lumbar support adjustment switch Front passenger seat lumbar support adjustment switch
37	20A	Climatronic control unit Driver seat heating control unit Front passenger seat heating control unit Front left seat heating Front right seat heating
38	30A	2006-2007: Front passenger side window regulator motor
39	20A	2006-2007: Multifunction switch Automatic gearbox control unit
40		Fresh air blower switch (for models without air conditioning system only)
41	15A	Rear window wiper motor
42	15A	Windscreen and rear window washer pump
43	–	–
44	20A	Trailer detector control unit Supply for turn signal, brake light, left tail light (2003-2005)
45	15A	Trailer detector control unit Supply for rear fog light, reversing light, right tail light (2003-2005)
46	5A	Heater control unit Climatronic control unit Left washer jet heater element Right washer jet heater element
47	5A	2006-2007: Power output module for left headlight
48	10A	Electric socket (for driving school only)
49	5A	Special vehicle fuse 6 Footwell light switch Warning buzzer switch

Fuses on left under dash panel

№	Amps	Function/component
A	30A	2005: Window regulator single fuse 2
B	30A	2003-2005: Window regulator single fuse
C	30A	–
D	–	–

Engine Compartment Fuse Box

Fuse Box Location

Push the two slides forward to unlatch the fuse cover.

Location of the fuses in the engine compartment: Audi A3 (2004, 2005, 2006, 2007)

Fuse Box Diagram

Version 1 (Low)

Assignment of the fuses in the engine compartment (low)

№	Amps	Function/component
F1	20A	Convenience system central control unit
F2	5A	Steering column electronics control unit
F3	5A	Onboard supply control unit
F4	30A	ABS control unit ABS hydraulic unit
F5	15A	Mechatronic unit for dual clutch gearbox
F6	5A	Control unit in dash panel insert
F7	–	–
F8	15A	Radio Navigation operating electronics control unit
F9	5A	Navigation system with CD drive control unit Navigation system tuner for TV Satellite radio Telephone transmitter and receiver unit Aerial amplifier for mobile telephone
F10	5A	Motronic control unit Motronic current supply relay Terminal 30 voltage supply relay
F11	20A	Auxiliary heater control unit
F12	5A	Data bus diagnostic interface
F13	30A	Engine control unit Diesel direct injection system control unit
F13	25A	Motronic control unit Engine control unit
F14	20A	Ignition coil 1 with output stage Ignition coil 2 with output stage Ignition coil 3 with output stage Ignition coil 4 with output stage
F15	15A	Lambda probe 1 heater after catalytic converter Lambda probe 2 heater after catalytic converter Lambda probe 3 heater after catalytic converter
F15	10A	Lambda probe 1 heater after catalytic converter
F15	5A	Automatic glow period control unit Fuel pump relay
F16	30A	ABS control unit ABS hydraulic pump
F17	15A	Treble tone horn Bass tone horn
F18	30A	Amplifier Amplifier with bass loudspeaker, on left in luggage compartment
F19	30A	Wiper motor control unit
F21	10A/15A	Lambda probe heater Lambda probe heater 2 Lambda probe 1 heater after catalytic converter
F22	5A	Brake pedal switch Clutch position sender
F23	15A	Fuel pressure regulating valve
F23	10A	Exhaust gas recirculation valve Charge pressure control solenoid valve Exhaust gas recirculation valve 2 Exhaust gas recirculation cooler change-over valve
F23	5A	Secondary air pump relay
F24	10A	Map-controlled engine cooling system thermostat Activated charcoal filter solenoid valve 1 Variable intake manifold change-over valve Camshaft control valve 1 Intake manifold flap motor
F25	40A	Onboard supply control unit (right side light, right main beam, right dipped beam, right turn signal, right fog light)
F26	40A	Onboard supply control unit (left side light, left main beam, left dipped beam, left turn signal, left fog light)
F27	50A	Automatic glow period control unit Glow plug 1~4
F27	40A	Secondary air pump motor
F28	40A	Terminal 15 voltage supply relay 2 Supply for the fuses (instrument panel): SC1, SC2, SC3, SC4, SC5, SC6, SC7, SC8, SC9, SC10, SC11, SC29, SC30, SC31, SC39, SC47, SC49
F29	50A	Supply for the fuses (instrument panel): SC18, SC20, SC32, SC33, SC34, SC35, SC36, SC37, SC44, SC45, SC48, and S131
F30	40A/50A	X-contact relief relay Supply for the fuses (instrument panel): SC40, SC41, SC42, SC46
SA1	150A/200A	Alternator
SA2	80A	Power steering control unit
SA3	50A	Radiator fan control unit Radiatorfan thermal switch Radiator fan
SA4	80A	Supply for the fuses (instrument panel): SC12, SC13, SC14, SC15, SC16, SC17, SC19, SC22, SC23, SC24, SC25, SC26, SC27, SC28, SC38 (is dropped from November 2005
SA5	80A	Supply for the fuses (instrument panel): SC12, SC13, SC14, SC15, SC16, SC17, SC19, SC22, SC23, SC24, SC25, SC26, SC27, SC28, SC38 (applicable from November 2005)
SA5	100A	Auxiliary air heater control unit (up to November 2005)
SA6	100A	Auxiliary air heater control unit (applicable from November 2005)
SA7	50A/80A	Option for special vehicles

Version 2 (High)

Under-hood fuse box diagram (ver.2): Audi A3 (2004, 2005, 2006, 2007)

Assignment of the fuses in the engine compartment (high)

No.	Nomina I value	Function/component
F1	30A	ABS control unit ABS hydraulic pump
F2	30A	ABS control unit ABS hydraulic unit
F3	20A	Convenience system central control unit
F4	5A	Onboard supply control unit
F5	15A	Treble tone horn Bass tone horn
F6	7.5A/15A	Fuel pressure regulating valve Fuel system pressurisation pump
F6	20A	2003-2005: Output stage
F6	30A	2003-2005: Ignition coil 1~6 with output stage
F7	5A	2003-2005: Brake light switch Brake pedal switch Clutch travel sender
F8	10A	2003-2005: Map-controlled engine cooling system thermostat Radiator fan control unit Exhaust gas recirculation valve Activated charcoal filter solenoid valve 1 Variable intake manifold change-over valve Camshaft control valve 1 Exhaust camshaft control valve 1 Intake manifold flap motor
F9	10A	2003-2005: Fuel pump relay Continued coolant circulation relay Automatic glow period control unit NOx sensor control unit – Continued coolant circulation pump NOx sender heater 2006-2007: Charge pressure control solenoid valve Activated charcoal filter solenoid valve 1 Turbocharger air recirculation valve
F10	10A	2003-2005: Secondary air pump relay Exhaust gas recirculation valve Charge pressure control solenoid valve Secondary air inlet valve Exhaust gas recirculation valve 2 Exhaust flap valve Lambda probe 1 heater after catalytic converter Lambda probe 2 heater after catalytic converter Fuel system diagnostic pump 2006-2007: Ar mass meter Fuel system diagnostic pump
F11	10A	2006-2007: Lambda probe heater Lambda probe heater 2
F11	25A	2003-2005: Motronic control unit Simos control unit
F11	30A	2003-2005: Diesel direct injection system control unit
F12	10A/15A	2003-2005: NOx sensor control unit Lambda probe heater Lambda probe heater 2 NOx sender heater 2006-2007: Lambda probe 1 heater after catalytic converter Lambda probe 2 heater after catalytic converter
F13	15A/20A	Mechatronic unit for dual clutch gearbox
F14	–	–
F15	10A	2006-2007: Continued coolant circulation pump
F15	40A	2003-2005: Starter
F16	5A	Steering column electronics control unit
F17	5A	Control unit in dash panel insert
F18	30A	Amplifier Amplifier with bass loudspeaker, on left in luggage compartment
F19	15A	Radio Navigation operating electronics control unit
F20	5A	Navigation system with CD drive control unit (2006-2007) Navigation system tuner for TV (2006-2007) Telephone transmitter and receiver unit Aerial amplifier for mobile telephone Satellite radio (2006-2007)
F21	10A	2003-2005: Navigation system with CD drive control unit – Navigation system tuner for TV
F22	–	–
F23	5A	2006-2007: Motronic control unit Motronic current supply relay
F24	5A	Data bus diagnostic interface
F25	–	–
F26	10A	2003-2005: Motronic control unit Motronic current supply relay
F26	5A	2003-2005: Terminal 30 voltage supply relay
F27	5A/10A	2003-2005: Heater element for crankcase breather (for models with heater element only)
F28	20A	2003-2005: Automatic gearbox control unit
F28	25A	2006-2007: Motronic control unit
F29	10A/20A	2003-2005: Injector, cylinder 1~4 / Injector, cylinder 1~6
F29	5A	2006-2007: Continued coolant circulation relay Secondary air pump relay
F30	20A	Auxiliary heater control unit
F31	30A	Wiper motor control unit
F32	10A	2003-2005: Injector, cylinder 1~4 Charge pressure control solenoid valve Activated charcoal filter solenoid valve 1 Turbocharger air recirculation valve
F33	15A	2003-2005: Fuel system pressurisation pump
F33	7.5A/15A	2003-2005: Fuel pressure regulating valve
F34	–	–
F35	–	–
F36	–	–
F37	–	–
F38	10A	2003-2005: Left headlight range control motor Right headlight range control motor 2006-2007: Activated charcoal filter solenoid valve 1 Variable intake manifold change-over valve Camshaft control valve 1 Exhaust camshaft control valve 1 Radiator fan control unit
F39	5A	2003-2005: Oil level and oil temperature sender 2006-2007: Brake pedal switch Clutch position sender
F40	20A	2003-2005: Supply for the fuses (instrument panel): SC1, SC2, SC3, SC4, SC5, SC6, SC7, SC8, SC9, SC10, SC11, SC29, SC31 (for models with battery in engine compartment only) 2006-2007: Ignition coil 1~4 with output stage
F41	10A	2003-2005: Air mass meter
F42	5A/10A	2003-2005: Fuel pump relay Air mass meter
F42	5A	2006-2007: Engine component current supply relay
F43	20A	2003-2005: Vacuum pump relay (for petrol engines with automatic gearbox only)
F43	30A	2006-2007: Ignition coil 1~6 with output stage
F44	10A	2003-2005: Air mass meter Fuel system diagnostic pump
F45	10A/15A	2003-2005: Lambda probe heater Lambda probe 1 heater after catalytic converter
F46	10A	2003-2005: Lambda probe heater 2 Lambda probe 1 heater after catalytic converter Lambda probe 2 heater after catalytic converter
F47	40A	Onboard supply control unit Left side light supply, left main beam, left dipped beam, left turn signal, left fog light
F48	40A	Onboard supply control unit Right side light supply, right main beam, right dipped beam, right turn signal, right fog light
F49	40A	Terminal 15 voltage supply relay 2 Supply for the fuses (instrument panel): SC1, SC2, SC3, SC4, SC5, SC6, SC7, SC8, SC9, SC10, SC11, SC29, SC30, SC31, SC47, SC49
F50	–	–
F51	40A	Secondary air pump relay Secondary air pump motor
F51	50A	Automatic glow period control unit
F52	40A/50A	X-contact relief relay Supply for the fuses (instrument panel): SC40, SC41, SC42, SC46
F53	50A	2003-2005: Supply for the fuses (instrument panel): SC32, SC33, SC34, SC35, SC36, SC37, SC44, SC45 (for models with battery in engine compartment only) Supply for the fuses (instrument panel): SC32, SC33, SC34, SC35, SC36, SC37 (for models with battery in luggage compartment only) 2006-2007: Supply for the fuses (instrument panel): SC18, SC20, SC32, SC33, SC34, SC35, SC36, SC37, SC44, SC45, SC48, and S131
F54	50A	2003-2005: Radiator fan thermal switch Radiator fan control unit
SA1	150A/200A	Alternator
SA2	80A	Power steering control unit
SA3	80A	Radiator fan control unit
SA4	80A	Window regulator single fuse Supply for the fuses: SC22, SC23, SC24, SC25, SC26, SC27 (for models with battery in luggage compartment only)
SA5	100A	Auxiliary air heater control unit
SA6	50A	Supply for the fuses: SC12, SC13, SC14, SC15, SC16, SC17, SC44, SC45 (for models with battery in luggage compartment only)
SA6	80A	Window regulator single fuse Supply for the fuses: SC12, SC13, SC14, SC15, SC16, SC17, SC22, SC23, SC24, SC25, SC26, SC27 (for models with battery in engine compartment only)
SA7	50A/80A	Option for special vehicles

Main Fuse Box

It is in luggage compartment (rear right).

№	Amps	Function/component
1	5A	Onboard supply control unit
2	125A	Supply for main fuse box, electronics box high, relay and fuse carrier, electronics box high
3	80A	Supply for main fuse box, electronics box high, relay and fuse carrier, electronics box high
4	30A	2005-2007: Amplifier for models with Bose sound system only 2005-2007: Supply for the fuses in the instrument panel: #12, 13, 14, 15, 16, 17, 19 2006-2007: Supply for the fuses in the instrument panel: #12, 13, 14, 15, 16, 17, 47