seems to have gone all weak (cue the plethora of puns)

but seriously, it seemed fine the other day, in fact it got stuck on in town much the amusement of the people waiting at the lights around me!

is there a dodgy contact behind the button on the wheel I can clean up or should I just replace the horn itself??

Yes...I'd rub it with some Vaseline.

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"Show me the Mini!"

That horn contact can melt a little and weld the contacts together if you hold it on and the horn is upgraded to a higher current device,or the contacts are old.

Give it a good clean up, and if you have an air horn for instance consider changing back or fitting a relay.

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

Fitting a relay to any current drawing component in a car regardless what it is always makes the function an improvement and also makes switches last longer. Using sand paper or any other abrasive on contacts does not do much good as it takes away the hardened surface off the contacts and exposes the softer core therefore when it arks again it melts and becomes worse. Fit a Relay and use a good quality one. It is always a help on a Mini with 40 odd year old switches.

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