Horn technology 1962 and 2015 used by General Motors, Chrysler, and Ford, North American market, includes but is not limited to:

    
  Horn honks to warn of danger      Horn honks to warn of danger
  Horn honks for lock feedback
  Horn honks from a key fob to "locate" car in parking lot
  Horn honks from a smartphone to "locate" car in parking lot
  Horn honks with "panic alarm"
  Horn honks with TPMS when filling tires with air
  Horn honks with remote start
  Horn honks with charge (E models)
  Horn honks with pedestrian friendly alert (E models)
  Horn honks to indicate key left in car
  Horn honks as part of car alarm signal