Horn Hi

Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION .)
Remove the set plate. (See SET PLATE REMOVAL/INSTALLATION .)
Remove the front bumper. (See FRONT BUMPER REMOVAL .) (See FRONT BUMPER INSTALLATION .)
Remove the horn. (See HORN REMOVAL/INSTALLATION .)
Apply battery positive voltage to horn terminal, and connect the horn retaining bolt to ground as shown in the figure, and then verify that the horn sounds.

Fig 1: Inspecting Horn Retaining Bolt
Courtesy of MAZDA MOTORS CORP.
- If the horn does not sound, replace the horn. (See HORN REMOVAL/INSTALLATION .)