Horn HI

Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
Remove the front bumper. (See FRONT BUMPER REMOVAL .) (See FRONT BUMPER INSTALLATION .)
Remove the horn HI. (See HORN REMOVAL/INSTALLATION .)
Apply battery positive voltage to horn HI terminal 1A, and connect the horn HI terminal 2A to ground as shown in the figure, and then verify that the horn HI sounds.

Fig 1: Checking Horn High Sounds

Courtesy of MAZDA MOTORS CORP.

If the horn HI does not sound, replace the horn HI. (See HORN REMOVAL/INSTALLATION .)