Horn Removal/Installation

WARNING: This page is about a different car, the 2018 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
Remove the set plate. (See SET PLATE REMOVAL/INSTALLATION .)
Remove the fresh-air duct installation bolts. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [SKYACTIV-G 2.5T] .) (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [SKYACTIV-G 2.5 (WITH CYLINDER DEACTIVATION)] .) (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [SKYACTIV-G 2.5 (WITHOUT CYLINDER DEACTIVATION)] .)
Remove the front bumper. (See FRONT BUMPER REMOVAL/INSTALLATION .)
Disconnect the connector.

Fig 1: Horn, Connector, Ground, Bolts With Torque Specification
Courtesy of MAZDA MOTORS CORP.
Remove the bolt.
Remove the ground. (RH only)
Remove the horn.
Install in the reverse order of removal.