Here is the pinout of the fuseboxes on a Mk2 petrol:
Engine compartment fusebox connector A:
A Junction unit supply from battery (+) M6 stud
Engine compartment fusebox connector B:
1 Headlamp washer pump motor supply
2 Main loads supply (prep.)
3 Not connected
4 Left fog lamp supply
5 Right fog lamp supply
6 Headlamp washer relay feed
7 Not connected
8 Not connected
9 INT / A for services (prep.)
10 INT / A for air con
11 INT / A supply input
12 Main beam headlamps relay feed
13 Not connected
14 Automatic gearbox relay feed
15 +50 inition switch (starting)
16 Fuel pump relay
17 Automatic gearbox relay feed
18 Automatic gearbox operation supply
19 Not connected
20 INT prep. main load
21 Horn relay feed
22 Right main beam headlamp supply
23 Fog lamp relay feed
24 Main beam headlamps supply (prep.)
25 Left main beam headlamp supply
26 Passenger compartment fan relay coil earth
27 Supply for high tone of two-tone horn
28 Supply for one-tone horn or low tone of two-tone horn
29 Not connected
30 +15 / 54 ignition switch (+ key)
31 Ignition switch supply
32 Interior fan supply
Engine compartment fusebox connector C:
A Radiator fan 2nd speed supply
B Supply for single stage stat switch for rad fan
C Single speed radiator fan 1st speed supply
Engine compartment fusebox connector D:
A Electric steering controlunit supply
B ABS control unit supply
Engine compartment fusebox connector E:
A Dashboard control unit supply (basic)
B Dashboard control unit supply (optional)
Engine compartment fusebox connector F:
1 Not connected
2 Heated filter supply
3 Automatic gearbox relay coil supply T20 (prep.)
4 Air con compressor supply
5 Air con compressor relay feed
6 Heated filter relay supply
7 Supply for Lambda sensor, vapour solenoid, speedo
8 +15 / 54 supply for ECU relay coils
9 +15 / 54 ECU key sensor
10 ECU relay coil supply
11 Fuel pump - electrostop relay feed
12 Engine control system relay feed
13 Not connected
14 Not connected
15 Not connected
16 Not connected
17 Supply from automatic gearbox relay T20 (prep.)
18 Supply injectors, coils, fuel pump
19 +50 electromagnet for starter motor
20 Not connected
21 Radiator fan 2nd speed relay feed
22 Heated filter relay feed
23 ECU battery (+) supply
24 Not connected
25 Not connected
26 Not connected
27 Not connected
28 Radiator fan 1st speed mono relay feed
29 Fuel pump - electrostop relay coil supply
30 Fuel pump - electrostop supply
31 ECU main loads supply
32 ECU (power) supply
Passenger compartment fusebox connector A:
1 Left and right headlamp alignment signal
2 Left and right headlamp alignment motor supply
3 Left dipped headlamp supply
4 Automatic gearbox serial line
5 City / normal electric steering control
6 TDS oil level
7 Switch / A for relay coils
8 Reversing control signal
9 Fuel pump supply
10 Windscreen wiper / two-way pump supply
11 Switch for ABS
12 Right dipped headlamp supply
13 + lights for heating / air con system
14 Brake light switch supply
15 Brake lights control signal
16 Brake signal for ABS
17 Switch for electric steering
18 Switch for traction control
19 Reversing switch / automatic gearbox system supply
20 Left and right headlamp alignment earth
Passenger compartment fusebox connector B:
A Battery (+) for services (prep.)
B Not connected
Passenger compartment fusebox connector C:
A Battery (+) for basic dashboard control unit
B Battery (+) for optional dashboard control unit
Passenger compartment fusebox connector D:
1 Left rear electric window supply
2 Right rear electric window supply
3 Sun roof supply
4 Heated seats supply
5 Top brake lamp supply
6 Brake light signal for trailer
7 Reversing signal
8 Passenger side reversing llight operation
9 Rearscreen wiper brake
10 CAN-bus A (aggregation prep. at rear)
11 Supply from fuse F32 (prep.)
12 Power current socket
13 Subwoofer supply
14 Power current socket
15 Heated rear windscreen supply
16 Door locking control
17 Right front electric window supply (prep.)
18 Door unlocking control
19 Electric mirrors supply / light
20 Rearscreen wiper motor supply
21 Heated seats control light
22 Seat belt warning lamp (prep.)
23 Rain sensor supply (F49) and current skt signal (prep.)
24 Switch for trailer
25 Number plate lamp supply (prep.)
26 Number plate lamp supply
27 Light supply (prep.)
28 CAN-bus B (aggregation prep. at rear)
29 Not connected
30 Left front electric window supply (prep.)
31 Left and right heated mirror
32 Fuel pump supply
Passenger compartment fusebox connector E:
1 Switch / A from ignition switch
2 Parking lights control signal from ignition switch
3 Switch for radio
4 Switch for radio phone (prep.)
5 CAN-bus B for radio
6 Switch for air bag
7 Radio and radio memory supply
8 Radio / radio phone supply (prep.)
9 Supply for cigar lighter
10 Dashboard control unit power earth
11 Switch from ignition switch
12 Radio / radio phone light
13 Cigar lighter light
14 Switch / A protected by F31 (prep.)
15 TDS engine oil level
16 City /normal electric steering control
17 CAN-bus A for radio
18 Not connected
19 Right front electric window supply
20 Left front electric window supply
Passenger compartment fusebox connector F:
1 Automatic gearbox fluid level serialline
2 Switch from F37 (prep.)
3 Not connected
4 Not connected
5 Seat belt warning light for inst.panel connector (prep.)
6 Not connected
7 Not connected
8 Headlamp alighment (prep.)
9 Preparation + lights
Passenger compartment fusebox connector G:
10 Headlamp alignment earth (prep.)
11 Heated rear window control
12 Switch for control panel
13 + lights signal from column switch
14 Headlamp alignment supply in inst. panel
15 Rearscreen wiper brake
16 Light system supply
17 Rearscreen wiper supply
18 Headlamp alignment control signal
Passenger compartment fusebox connector X (connects directly pin for pin to Body computer socket Y):
1 Central locking supply
2 Top brake light signal
3 Reversing signal
4 Not connected
5 CAN-bus B to dashboard control unit
6 Heated rear window relay coil R11
7 CAN-bus A to dashboard control unit
8 Dipped headlamps relay coil R1
9 INT supply for body computer (ignition on, before F37)
10 Door locking motors
11 Door unlocking motors
12 Lights system supply from ignition switch
13 INT supply for Instrument panel connector (ignition on after F37)
14 Sunroof, electric windows relay R13
15 Heater controls and cigar lighter illumination and number plate lamps
16 Not connected
17 Services / SMBT services supply
18 Body computer supply (immob., CAN-bus, side lights, rear fog lamp)
19 Supply for indicators, hazards, instrument panel connector (via F53)
20 Central locking earth
red
Engine compartment fusebox connector A:
A Junction unit supply from battery (+) M6 stud
Engine compartment fusebox connector B:
1 Headlamp washer pump motor supply
2 Main loads supply (prep.)
3 Not connected
4 Left fog lamp supply
5 Right fog lamp supply
6 Headlamp washer relay feed
7 Not connected
8 Not connected
9 INT / A for services (prep.)
10 INT / A for air con
11 INT / A supply input
12 Main beam headlamps relay feed
13 Not connected
14 Automatic gearbox relay feed
15 +50 inition switch (starting)
16 Fuel pump relay
17 Automatic gearbox relay feed
18 Automatic gearbox operation supply
19 Not connected
20 INT prep. main load
21 Horn relay feed
22 Right main beam headlamp supply
23 Fog lamp relay feed
24 Main beam headlamps supply (prep.)
25 Left main beam headlamp supply
26 Passenger compartment fan relay coil earth
27 Supply for high tone of two-tone horn
28 Supply for one-tone horn or low tone of two-tone horn
29 Not connected
30 +15 / 54 ignition switch (+ key)
31 Ignition switch supply
32 Interior fan supply
Engine compartment fusebox connector C:
A Radiator fan 2nd speed supply
B Supply for single stage stat switch for rad fan
C Single speed radiator fan 1st speed supply
Engine compartment fusebox connector D:
A Electric steering controlunit supply
B ABS control unit supply
Engine compartment fusebox connector E:
A Dashboard control unit supply (basic)
B Dashboard control unit supply (optional)
Engine compartment fusebox connector F:
1 Not connected
2 Heated filter supply
3 Automatic gearbox relay coil supply T20 (prep.)
4 Air con compressor supply
5 Air con compressor relay feed
6 Heated filter relay supply
7 Supply for Lambda sensor, vapour solenoid, speedo
8 +15 / 54 supply for ECU relay coils
9 +15 / 54 ECU key sensor
10 ECU relay coil supply
11 Fuel pump - electrostop relay feed
12 Engine control system relay feed
13 Not connected
14 Not connected
15 Not connected
16 Not connected
17 Supply from automatic gearbox relay T20 (prep.)
18 Supply injectors, coils, fuel pump
19 +50 electromagnet for starter motor
20 Not connected
21 Radiator fan 2nd speed relay feed
22 Heated filter relay feed
23 ECU battery (+) supply
24 Not connected
25 Not connected
26 Not connected
27 Not connected
28 Radiator fan 1st speed mono relay feed
29 Fuel pump - electrostop relay coil supply
30 Fuel pump - electrostop supply
31 ECU main loads supply
32 ECU (power) supply
Passenger compartment fusebox connector A:
1 Left and right headlamp alignment signal
2 Left and right headlamp alignment motor supply
3 Left dipped headlamp supply
4 Automatic gearbox serial line
5 City / normal electric steering control
6 TDS oil level
7 Switch / A for relay coils
8 Reversing control signal
9 Fuel pump supply
10 Windscreen wiper / two-way pump supply
11 Switch for ABS
12 Right dipped headlamp supply
13 + lights for heating / air con system
14 Brake light switch supply
15 Brake lights control signal
16 Brake signal for ABS
17 Switch for electric steering
18 Switch for traction control
19 Reversing switch / automatic gearbox system supply
20 Left and right headlamp alignment earth
Passenger compartment fusebox connector B:
A Battery (+) for services (prep.)
B Not connected
Passenger compartment fusebox connector C:
A Battery (+) for basic dashboard control unit
B Battery (+) for optional dashboard control unit
Passenger compartment fusebox connector D:
1 Left rear electric window supply
2 Right rear electric window supply
3 Sun roof supply
4 Heated seats supply
5 Top brake lamp supply
6 Brake light signal for trailer
7 Reversing signal
8 Passenger side reversing llight operation
9 Rearscreen wiper brake
10 CAN-bus A (aggregation prep. at rear)
11 Supply from fuse F32 (prep.)
12 Power current socket
13 Subwoofer supply
14 Power current socket
15 Heated rear windscreen supply
16 Door locking control
17 Right front electric window supply (prep.)
18 Door unlocking control
19 Electric mirrors supply / light
20 Rearscreen wiper motor supply
21 Heated seats control light
22 Seat belt warning lamp (prep.)
23 Rain sensor supply (F49) and current skt signal (prep.)
24 Switch for trailer
25 Number plate lamp supply (prep.)
26 Number plate lamp supply
27 Light supply (prep.)
28 CAN-bus B (aggregation prep. at rear)
29 Not connected
30 Left front electric window supply (prep.)
31 Left and right heated mirror
32 Fuel pump supply
Passenger compartment fusebox connector E:
1 Switch / A from ignition switch
2 Parking lights control signal from ignition switch
3 Switch for radio
4 Switch for radio phone (prep.)
5 CAN-bus B for radio
6 Switch for air bag
7 Radio and radio memory supply
8 Radio / radio phone supply (prep.)
9 Supply for cigar lighter
10 Dashboard control unit power earth
11 Switch from ignition switch
12 Radio / radio phone light
13 Cigar lighter light
14 Switch / A protected by F31 (prep.)
15 TDS engine oil level
16 City /normal electric steering control
17 CAN-bus A for radio
18 Not connected
19 Right front electric window supply
20 Left front electric window supply
Passenger compartment fusebox connector F:
1 Automatic gearbox fluid level serialline
2 Switch from F37 (prep.)
3 Not connected
4 Not connected
5 Seat belt warning light for inst.panel connector (prep.)
6 Not connected
7 Not connected
8 Headlamp alighment (prep.)
9 Preparation + lights
Passenger compartment fusebox connector G:
10 Headlamp alignment earth (prep.)
11 Heated rear window control
12 Switch for control panel
13 + lights signal from column switch
14 Headlamp alignment supply in inst. panel
15 Rearscreen wiper brake
16 Light system supply
17 Rearscreen wiper supply
18 Headlamp alignment control signal
Passenger compartment fusebox connector X (connects directly pin for pin to Body computer socket Y):
1 Central locking supply
2 Top brake light signal
3 Reversing signal
4 Not connected
5 CAN-bus B to dashboard control unit
6 Heated rear window relay coil R11
7 CAN-bus A to dashboard control unit
8 Dipped headlamps relay coil R1
9 INT supply for body computer (ignition on, before F37)
10 Door locking motors
11 Door unlocking motors
12 Lights system supply from ignition switch
13 INT supply for Instrument panel connector (ignition on after F37)
14 Sunroof, electric windows relay R13
15 Heater controls and cigar lighter illumination and number plate lamps
16 Not connected
17 Services / SMBT services supply
18 Body computer supply (immob., CAN-bus, side lights, rear fog lamp)
19 Supply for indicators, hazards, instrument panel connector (via F53)
20 Central locking earth
red
