2015 Hyundai Accent Electrical System

My horn is honking uncontrollably especially, when making left turns. Right turns, sometimes. Confusing a lot of drivers in the street and also some has become aggressive. Initially, I thought my hand was accidentally hitting the horn until I recently became worse over the past week or so.

ON 6/8/15 WHEN I STOPPED AT A TRAFFIC LIGHT, THE BATTERY LIGHT CAME ON AND THE CAR STALLED. AFTER I TURNED IT OFF AND TURNED IT ON AGAIN, THE PROBLEM DISAPPEARED. ON 7/27/15, A SIMILAR SITUATION RECURRED, AGAIN AFTER STOPPING AT A TRAFFIC LIGHT. THIS TIME MULTIPLE WARNING LIGHTS CAME ON, INCLUDING ENGINE OIL PRESSURE, PARKING BRAKE/BRAKE FLUID AND SOMETHING ELSE. THE CAR STALLED AGAIN. AND AGAIN AFTER TURNING IT OFF AND ON THE PROBLEM DISAPPEARED AND THEN I COULD DRIVE NO PROBLEM. VERY LIKELY IT MAY BE A COMPUTER MALFUNCTION. WITH THIS ISSUE THE CAR IS UNPREDICTABLE, UNRELIABLE AND RESPECTIVELY DANGEROUS. UPDATED 09/09/15*LJ.....UPDATED 09/22/15 *BF UPDATED 12/9/2015 *JS