Series 3 trouble with Horn

Just about finished the series 3 rebuild and have a silly problem in that the horn don't work, i have tested the horn with a seperate feed from battery and it works fine, have tested the feed wire and that is fine, tried a seperate earth to it, and don't work, so either i am missing something or i am going mad, been at it all day today, What else could it be ?

Iirc the horn switches to earth so power looks like it's getting everywhere it should if the switch is dodgy.......if you see what I mean

Horn supply on series 3 is from brown wire from ignition switch too the column switch then to horn which is earthed after horn.

ok, i have got a new switch so ill try that, thanks for advice

Put new indicator switch on and it works fine now, thanks again

iirc the horn wire inside the indicator switch can come off or the connection break sometimes, when I got my s3 the horn had been wired separately to a flick switch and wouldn't work from the stalk when I tried to wire it back, so I did the same as you, got a new switch and everything was fine