horn started going off after stopping for gas on 2008 Hyundai Tucson

My horn started blarring for no reason when I stopped for gas. Couldn't get it to stop even after pressing button on key pad. Couldn't start car while horn blarring. Did this three times in a row but finally stopped on it's own. Then I could start my car.

Asked by for the 2008 Hyundai Tucson
Your theft deterrent system is giving you trouble. Get it checked by a Hyundai or Mitsubishi technician.
If you want to find a specialist, here's our directory link for you: