Tap the horn
(Other definitions for toot that I've seen before include "Horn's sound (T, not H)" , "Brief blast on a horn" , "Briefly blow" , "Use horn" , "Short sound of horn" .)
(Other definitions for honk that I've seen before include "Toot one's horn" , "Cry of a goose - sound of a horn" , "Toot of a horn - cry of a goose - smell nasty" , "Cry of the wild goose" .)
(Other definitions for beep that I've seen before include "Sound of pager" , "High-pitched noise" , "Short high-pitched sound from an electronic device" , "Alarming noise" , "Sound of a horn" .)