Heater assembly

Hi all, earlier I took the little rad out my heater box to clean it as even by series standards it was bad. when i took it off i noticed a little solid wire sitting behind it that goes somewhere into the other side of the dash, but i cant see where, if anywhere, it goes on the heater. Its had a 200tdi engine conversion and there's a few wires which aren't actually connected which is a bit worrying. The fan is working great so it can't be off that. any help would be great thanks

there shouldn't be a wire going through the heater box as far as i can remember

sounds like a PO mod' to me, trace it back and see if it's needed

I'll have a go but don't fancy takin all the dash out again already done it 3 times this week ha ha i'll see if it works without it then cheers for the help