1. Insert a small screwdriver into the slot and gently pry open the transmitter.

2. Press the portion of the battery indicated by A and remove the battery.

3. Install a new battery (CR2025) into the front portion of the holder with the positive pole (+) facing up. Press on the B portion of the battery to set the battery.
4. Align the front and back covers and snap the transmitter shut.
Battery specification Lithium CR2025 × 1
Note

Door lock timer unit id code change
Transmitter battery inspectionMazda 6 Service Manual: Direct Mode
Direct mode can be used for temporarily switching gears by operating the steering
shift switch while the vehicle is being driven with the selector lever in the D
range.
While in direct mode, the D and M indication illuminate and the gear position
in use is illuminated. Direct mode is canceled ...
Mazda 6 Service Manual: Supplemental 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 (some models), crash sensors, and diagnostic module (SAS
unit).
Seat belt pretensioners
Front air bag sensor ...