90% of the time, it is the horn contact mounted behind the steering wheel. Pull the steering wheel and you will see a brass ring. Pull it off and put a small washer under it at the three screws. This will help it have a better contact with the pin. You can get a replacement pin from the dealer and just pull the switch assy and it has a C-clip that you need to remove and undo the wire and replace.

Jeff

It's all good!
83 Shortbed stepside lots of mods
82 Shortbed fully restored
85 Shortbed daily driver
88 4-runner-Wife's daily driver