Originally Posted by DaiBach
Thank you both - I'm guessing the previous owners (a very large family of rats) did more work behind the dashboard . After 6 months I'm still finding poop where I least expect it !

Still trying to get my head around the circuitry without unraveling the loom - would the black wire here at the fuse box be a direct connection to the positive on the horn. I've tried a circuit tester but there was no reading so I suspect not (or else it was gnawed)

I guess, what I'm trying to ask is how to trace the purple/black electrical wire that leads from the indicator stem as I'm not sure how that gets to be the black wire that connects to the actual horn.

Out of curiosity - could anyone tell me what those 2 unmarked switches do ?

Would strongly suggest you replace that heavily corroded fuse box and spade connectors to it. If not now it will create issues in the future with high resistance or open circuits.

According to wiring diagram you should have a live brown wire feeding a dedicated fuse with purple wire passing the live feed onto horn push which then connects to horn with purple/black wire. You can see such wires from/to left hand fuse in your photo below.

[Linked Image]

The horn(s) are grounded locally to complete the circuit when operated. This is the reverse of normal practice where the horn push operates in the ground leg, and for good reason.

No idea what the black (normally ground) wire is doing in the vicinity, but please don't be tempted to put it anywhere near a live feed until you know where it goes!

Last edited by RichardV6; 01/11/21 08:09 AM.
Richard

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