Fusebox fire! Relay 15 (258) What is it!?

Trying to start my 8v gti for the first time on twin carbs. Lots of wires are loose atm as they are redundant from the kjet in the engine bay yet to sort out. Turning it over playing with the dizzy advance and i saw smoke coming from behind the dashboard!  

Ripped the lower dash out and dropped the fusebox. Took me a while to find the source of the problem but the 4 or 5 brown wires coming out the back of relay number 15 (also has 258 on the side) have melted all over the other wires!  

Can anyone please tell me what this relay does and what could of caused the wires to melt!?

you looked at this?

The Mk1 Golf Owners Club
all the brown wires are Earth wires and some go to the rosette.

Thanks for that, dont know how i missed it. Looking at it my no.15 relay is in the position of the no.17 in the pictures, and from the lists the only 1 that seems to make sense is the 85-89 style fusebox in which no.15 is for the fuel injection power supply. But mine is a caddy sport from 92. I guess it could have the same style fuse box but it looks to be just earth wires leaving the relay?

Very confused as to whats happened and what ive done to cause it. Would the fact some/none of the fuel injection wires are disconnected in the engine bay?

Right so ive traced the wires best I can without cutting any of them out the loom, this is what Ive found:

Relay 15 had 4 wires, excluding ones which bridge 2 sides of a relay.

1x Brown/White going from relay 15 to engine bay loom
1x Red/Black going from relay 15 to a connector which is at the back of the row of fuses
1x Red/Black going from relay 15 to engine bay loom
1x Brown going from relay 15 to relay 57

Relay 57 Has 6 wires.

1x Brown from relay 57 to Earth bank
1x Black from relay 57 to negative connection on fusebox
1x Black from relay 57 to engine bay loom
1x Brown/Black from relay 57 to engine bay
1x Red/Black from relay 57 to engine bay
1x Red/Black from relay 57 to relay position 4 (no relay present)


*The engine bay loom im referring to holds the wires for the fuel injection setup on the old inlet mani, the coil, and some senders at the front of the block.

Ive tried to narrow down where the wires lead to:

Red/Black can is either Coil/fuel inj./Coolant flange sender
Brown/White is either Fuel inj./Vac pipe & related wires from inlet mani to dizzy
Black is either Coil/Fuel inj.
Brown/Black must be fuel inj.


Any ideas where the problem could be :i_dont_kn