1. Disconnect the negative battery cable..
2. Remove the rear combination light..
3. Remove the rear bumper..
4. Remove the nuts and remove the rear bumper reinforcement.

5. Install in the reverse order of removal.
Rear Bumper Disassembly/Assembly
Rear Bumper Removal/InstallationSupplemental Restraint System Components
(With Front Passenger Occupant Classification System)
(Without Front Passenger Occupant Classification System)
Driver/Front passenger inflators and air bags
Roll-over sensor * , crash sensors, and diagnostic module (SAS unit)
Seat belt pretensioners
Front air bag sensors
Side c ...
Stop Vehicle in Safe Place Immediately
If any of the following warning lights turns on, the system may have a
malfunction. Stop the
vehicle in a safe place immediately and contact an Authorized Mazda Dealer.
...
Tires
For reasons of proper performance, safety,
and better fuel economy, always maintain
recommended tire inflation pressures and
stay within the recommended load limits
and weight distribution.
WARNING
Using Diff erent Tire Types:
Driving your vehicle with diff erent
types of tires ...