Audi A4 B7 (2004 – 2007) fuse and relay

Audi A4 B7 is the third generation of the Audi A4. Produced in 2004, 2005, 2006 and 2007. This is an updated version of B6. Our material presents diagrams of relay and fuse boxes Audi a4 b7 with a description of the purpose of the elements. The fuse responsible for the cigarette lighter is marked.

audi a4 b7

Fuse descriptions may vary depending on the year of manufacture, equipment and type of vehicle engine. The current assignment should be in your operating manual and also on the back of the fuse box cover on the back of the dashboard.

Passenger compartment

Main fuse box

This box is located on the left side of the dashboard behind a plastic cover.

location of the fuse box a4 b7


fuse block diagram audi a4 b7


110A air conditioner
25A legroom lights
35A overwhelmed windshield washer jets
45A cooling fan
510A telephone, engine oil level sensor, multifunction switches, heated rear seats, rear window shade, automatic transmission (gear shift)
65A air conditioner (air quality assessment sensor), pressure sensor
710A Electronic Stability Program (ESP), Brake Light Switch, Clutch Pedal Sensor, Steering Angle Sensor
85A phone
915A brake booster (vacuum pump)
105A automatic headlight range control. Adaptive light right
1210A diagnostic socket
1310A steering column module
1410A brake lights
1510A instrument cluster, navigation system
165A garage door opener
1710A parking assist, ride height control, tire pressure monitoring, rain / light sensor
185A Adaptive light (cornering light) left
1915A fog light
2215A driver / front passenger door
2315A rear doors
2420A comfortable electrical equipment with central control
2530A heater fan
2630A rear window heating
2730A trailer socket (control unit)
2820A fuel pump, diesel auxiliary pump
3020A lift-slide roof panel
3115A automatic transmission, diagnostic socket, auto-shielded interior mirror
3220A trailer socket
3315A cigarette lighter
3415A missing
3520A socket in the trunk
3630A wiper
3730A windscreen washer pump and headlight cleaning device
3815A comfort electrical equipment with central control, trunk release
3920A radio system
4025A beep
4130A autonomous heater
4225A Electronic Stability Program (ESP)
4315A motor control
4435A seat heating

Fuse number 33 at 15A is responsible for the cigarette lighter.

Under-dash fuse and relay boxes

Box 1 diagram

block a4 b7


4Taxi-hands-free alarm system control unit 3
BOptional equipment
H(50A) Anti-lock braking system (ABS)
G(40A / 60A) Cooling fan motor control unit 1
F(10A) Service vehicles
ECooling Fan Motor Control Unit 2 – If Equipped

Box 2 diagram

Audi A4 B7 block in salon


1Fuel pump relay – petrol
2Power steering control unit (Servotronic) (if fitted)
3Horn relay (dual tone)
4Brake Booster Vacuum Pump Relay (If Equipped)
6Relay for auxiliary ignition circuits
F2(10A) Thermal fuse for the electric rear window shade
F4(30A) Thermal fuse, rear power windows
F5(10A) Power seats (lumbar support adjustment)
F6(30A) Thermal fuse, front power windows
F7(30A) Trailer socket

Box 3 diagram

shield for 3 relays


2Coolant Heater Relay 2 – High Power
3Coolant Heater Relay 1 – Low Power
F1(30A) Additional heater – 2003
F2(40A) Coolant heater
F3(60A) Coolant heater

Engine compartment

Fuse box


block a4 b7

This box is located under the ECM / TCM (battery section). Several decryption options are possible.

Description for gasoline engines

1Coolant heater relay (V6)
2Transmission control relay (Multitronic)
3Exhaust air pump relay
4Coolant pump motor control unit (AMM / BDV)
5Start inhibit switch relay (if equipped)
F1(15A) Engine management system, brake light switch (brake pedal position sensor)
F2(40A) Exhaust air pump motor
F3(15A) Automatic transmission control system (6-speed automatic / Multitronic)

Description for diesel engines

1Fuel boost pump relay
2Transmission control relay (Multitronic)
3Glow plug relay
4Engine control relay
5Start inhibit switch relay / reversing lamp relay (Multitronic)
F1(15A) Engine management system, brake light switch (brake pedal position sensor)
F2(60A / 80A) Glow plugs
F3(15A) Automatic transmission control system (6-speed automatic / Multitronic)
F4(60A) Glow plugs

Main fuse on battery

main fuse

Additional Information

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Comments 4

  • Hi lads me avant 08 stopped ! Guel pump ????? How do i find out

  • Why can’t somebody give me the part#.for the main relay.that send to coil and spark plugs is it main relay for ecm.if both I need both relay part #2005a4 2.0 trobo.front.wheel drive.please.

  • I fitted a new high pressure pump for m Audi A4 B7 Tfsi 2006 petrol but it feels like I have more problems now.The high pressure pump is not releasing pressure from the ,pressure release valve.I have to do it manually.Please advice.Thank you.

  • Hi i have my audi a4 3.0 tdi quattro not power in injectors can someone tell me where’s the relay of injectors please

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