Trunk Lid

WARNING: This page is about a different car, the 2011 Mazda RX-8. However, it is still accessible from the selected car via links, so may be relevant.

Disconnect the negative battery cable.
Remove the rear bumper. (Refer to the REAR BUMPER REMOVAL/INSTALLATION in appropriate Body Panels article .)
Detach the request switch from the rear bumper.
Install in the reverse order of removal.

Fig 1: Identifying Request Switch, Connector And Rear Bumper

Courtesy of MAZDA MOTORS CORP.