Your horn button is the ground in the stock configuration. It's not powered. Someone with more knowledge of your type of set up than me will have to chime in but if it were me I'd run a separate hot wire to a separate switch to power the horn or use a stock horn. They are plentiful and relatively cheap on ebay.


Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.