Fuse box diagram — AUDI A3 (2003–2009)
Other generations: 1996–2003
Type what stopped working — headlight, wipers, lighter — and see which position powers it, and at how many amps.
2003–2009 159 fuses
28 relays 6 boxes
Fuse box 1 (2003+)
79
10A
1
Diagnostic connector
10A
1
Lighting switch
5A
2
ABS with EDL control unit
5A
2
TCS/ESP button
10A
3
Power steering control unit
10A
4
Additional heater
10A
4
Air quality sensor
10A
4
Air-conditioning high-pressure sensor
5A
5
Clutch pedal position sensor
5A
5
Brake light switch
5A
5
Brake pedal switch
5A
6
Diagnostic socket
5A
6
Trailer detection control unit
5A
7
Heated driver's seat
5A
7
Heated passenger's seat
5A
7
Headlight range control
5A
7
Control unit
5A
7
Heated rear seat(s) switch
10A
8
Navigation control unit
10A
8
Parking assistance control unit
10A
8
Automatic anti-dazzle rear-view mirror
10A
8
Garage door opener
5A
9
4WD control unit
5A
10
Tiptronic switch
10A
11
Trailer detection control unit
10A
12
Door control unit, front left
10A
12
Door control unit, front right
10A
13
Diagnostic connector
10A
13
Brake light switch
5A
14
Automatic transmission control unit
10A
15
Onboard supply control unit
10A
16
Climate control unit
10A
16
Additional heater remote control receiver
10A
16
Heater control unit
5A
17
Convenience electrics
5A
18
Parking assistance control unit
5A
18
Navigation control unit
5A
18
Tiptronic switch
?
19
Not used
?
20
Not used
?
21
Not used
40A
22
Blower control
20A
23
Headlight washer relay
20A
23
Headlight washer pump
20A
24
Cigarette lighter
30A
25
Heated rear windscreen
20A
26
12V socket
15A
27
Fuel pump
15A
27
Fuel pump relay
?
28
Not used
10A
29
Airbag warning light
?
30
Not used
5A
31
Reversing light(s) switch
5A
31
Automatic gearbox control unit
?
32
Not used
25A
33
Sliding roof control unit
20A
34
Heated rear seat(s) control unit
5A
35
Vehicle inclination sender
5A
35
Interior monitoring
5A
35
Alarm horn
10A
36
Driver's seat adjustment
10A
36
Passenger's seat adjustment
20A
37
Climate control unit
20A
37
Heater control unit
?
38
Not used
?
39
Not used
40A
40
Blower
15A
41
Rear wiper relay
15A
41
Rear washer relay
15A
42
Onboard supply control unit
?
43
Not used
20A
44
Trailer detection control unit
15A
45
Trailer detection control unit
5A
46
Heated washer jets
5A
46
Heater control unit
5A
46
Climate control unit
?
47
Not used
?
48
Not used
?
49
Not used
Fuse box 2 (2003+)
9
relay
R1
Terminal 15 voltage supply relay
relay
R2
Heated seats relay
relay
R3
Not used
relay
R4
Terminal 30 voltage supply relay
relay
R5
Heated rear windscreen relay
relay
R6
Horn relay
relay
R7
Windscreen washer pump
relay
R8
Washer pump, rear (5-door)
relay
R9
X contact relief relay
Fuse box 3 (2003+)
9
?
A
Not used
?
B
Power window controls
?
C
Not used
?
D
Not used
relay
R1
Headlight washer relay
relay
R2
Fuel pump relay
relay
R3
Not used
relay
R4
Not used
relay
R5
Not used
Fuse box 4 (2003+)
79
30A
1
ABS (hydraulic modulator/pump)
30A
2
ABS (hydraulic unit)
20A
3
Convenience electrics
5A
4
Onboard supply control unit
20A
5
Horn
5A
6A
Fuel consumption meter
20A
6B
No information available
5A
7
Clutch pedal position sensor
5A
7
Brake light switch
5A
7
Brake pedal switch
10A
8
EGR and canister purge solenoid
10A
8
Inlet manifold valve control motor
10A
8
Cooling fan control unit
10A
8
Valve camshaft timing
10A
8
MAP-controlled engine cooling thermostat
10A
8
Intake manifold flap
10A
9
NOx controller
10A
9
Glow plug control unit
10A
9
Fuel pump relay
10A
10
Secondary air pump relay
10A
10
Lambda probe heating
10A
10
NOx controller
10A
10
EGR valve
10A
10
Charge pressure control solenoid
25A
11A
Motronic control unit
25A
11A
Simos control unit
30A
11B
Diesel direct injection system control unit
15A
12
Lambda probe heating
20A
13
Automatic transmission control unit
?
14
Not used
40A
15
Starter
15A
16
Steering column electronics control unit
10A
17
Control unit with display in dash panel insert
30A
18
Amplifier
15A
19
Radio
5A
20
Telephone
5A
20
Telematics
10A
21
Navigation system
10A
21
CD player/changer
?
22
Not used
?
23
Not used
10A
24
Diagnostic socket
?
25
Not used
10A
26A
Motronic control unit
5A
26B
Terminal 30 voltage supply relay
10A
27
Crankcase breather
20A
28
Automatic transmission control unit
20A
29
Ignition coils 1-4
20A
30
Additional heater control unit
25A
31
Wiper motor
10A
32
Injectors cylinders 1-4
15A
33
Fuel pump
?
34
Not used
?
35
Not used
?
36
Not used
?
37
Not used
10A
38
Headlight range control
5A
39
Oil level sensor
5A
39
Oil temperature sensor
30A
40
Terminal 15, voltage supply shut-off
?
41
Not used
5A
42A
Fuel pump relay
10A
42B
Mass airflow meter
20A
43
Vacuum pump relay
?
44
Not used
10A
45
Lambda probe heating
?
46
Not used
40A
47
Onboard supply control unit
40A
48
Onboard supply control unit
?
49
Not used
?
50
Not used
40A
51A
Secondary air pump relay
relay
R1
Terminal 15 voltage supply relay
relay
R2
Terminal 50 voltage supply relay
relay
R3
Fuel pump relay
relay
R4
Terminal 30 voltage supply relay
relay
R4
Or
relay
R4
Simos control unit
relay
R4
Motronic power supply relay
Fuse box 5 (2003+)
6
relay
R1
Not used
relay
R2
Glow plug control unit
relay
R3
Not used
relay
R4
Not used
relay
R5
Secondary air pump relay
relay
R6
Not used
Fuse box (2003+)
5
5A
1
Onboard supply control unit
30A
FL4
Amplifier
30A
FL4
Or
30A
FL4
Not used
relay
R1
Battery cut-out relay
No position matches. Try one word — “headlight”, “pump”, “window”.
Fuse colours follow the blade-fuse standard (DIN 72581-3 / SAE J1284) and are derived from the rating. The number is what counts — older torpedo fuses use a different colour scheme. Cross-check the lid of the box.
Repair procedures for AUDI
Step-by-step procedures from the workshop database for this make.
- Removing and installing toothed belt · 56 torque figures
- Removing engine · 41 torque figures
- Removing camshaft timing chain from camshafts · 38 torque figures
- Installing engine · 36 torque figures
- Removing and installing camshaft timing chain · 29 torque figures
- Removing timing chains from camshafts · 28 torque figures
- Removing and installing sump (top section) · 25 torque figures
- Removing and installing camshaft timing chains · 24 torque figures
Fuse keeps blowing?
A blown fuse is a symptom, not the cause. Tell TorqFix which position it is and what the car does.
Ask about my car →Who makes these pages, and how
TorqFix was built by a mechanic — after a 2,700 km drive with five roadside repairs that no diagnostic tool could explain.
The figures on this page come from manufacturer workshop documentation and are shown as they are. The page is assembled automatically from that data — it is not written by an AI. The AI works in the chat, where it answers for your specific car. It writes nothing here.
Variants of the same model differ. Check the year and the label on the box in your car before pulling a fuse.
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The story behind TorqFix →Workshop data on this page last updated 22 Aug 2026.