Horn fuse blowing

[Elliottt]

A few weeks ago I noticed the horn and interior light wasn't working anymore in my ffr perentie, sure enough the horn fuse had blown I put a new fuse in, all was good until I started the engine, which blew the fuse straight away

There are two purple wires leaving the load side of the horn fuse, If I disconnect one of those wires [at the fuse box], the horn and interior light work and the fuse doesn't blow, if i disconnect the other and reconnect the first, the horn and interior light don't work and the fuse blows when the engine starts so the fault is somewhere along the wire that doesn't go to the horn and the Interior light

Does anybody know where that purple wire goes? Everything else seems to be working, even with the troublesome wire disconnected

[Ravvin]

I just had a look at the wiring diagram and there should be 2 purple wires coming out of the fuse. One goes to the horn switch/interior light. The other goes to something just labelled as Aux Feed, which then has a wire coming off that going to something labelled Spare. Both the Aux Feed and the Spare appear to be socket connectors of some sort.
 
If you know where those sockets are, you could follow the wires back. I'm betting you will find a rub through and short.

Greg.

[Elliottt]

Thanks, now having looked at the wiring diagram I see what you mean. I assume the connectors for aux feed and spare are stashed away somewhere under the dash. I think i'll just leave the wire disconnected at the fuse box, that way there will be one less live cable floating around in there. After spending several days poking through the electrical system I went out and bought a master battery isolator switch, there's just way too many dodgy terminations and spaghetti wiring, the thing is a fire waiting to happen. I also wired the headlights and horn through relays I couldn't believe the whole headlight current was being switch through those pathetic wires They run much brighter and the horns louder now too 

[Ravvin]

Wiring the headlights directly through the switch seems to be a Land Rover thing. It may have been ok with the old low wattage bulbs, but not for the modern types.

I previously had an early Range Rover and it was also wired like that. The headlights were always fairly dim. On a 300km drive late one night, using mostly high beam, I could smell a melting plastic/electrical shorting smell. Next morning I couldn't move the headlight switch lever. The contacts had gotten so hot, the plastic surrounding them had melted and stuck to the end of the lever.
I bought a new switch, some heavier wiring and 2 relays and found the lights were brighter than I had ever seen them.

Go Lucas! (away)

Greg.