Mine packed up, and it took me ages to find it (tucked up in front of the left wheel).
It's an old-fashioned one with an adjuster screw! I gave it a squirt of penetrating fluid, left it a while, and managed to get it going again. Use the adjuster to optimise it.
The horn is prone to rust where it is instaled behind the front bumper on the passenger's side. Yours could have a bad ground connection. Try taking it off and cleaning it up. You can test it by touching the wire to the positive post on the battery. Set it on bare metal where it will be grounded. When mine went I installed the replacment on an unused bolt hole in the engine compartment on the passenger side wheel well. It's not as likely to rust out there.
Original owner of silver grey carburetted 1989 Festiva. 105k km as of June 2006. 140k km as of June 2021.
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