If there is the possibility of a collision with a vehicle ahead, the beep sounds continuously and a warning is indicated in the multi-information display and the active driving display.

Smart Brake Support (SBS) (Some models)
Stopping The Smart Brake Support (SBS) System OperationMazda 6 Owners Manual: Rear side seat belt removal/installation
Caution
The ELR has a spring that will unwind if the retractor's cover is
removed. The spring cannot be rewound by hand. If this occurs, the ELR will
not work properly. Therefore, do not disassemble the retractor.
4SD
1. Fold the rear seat back.
2. Remove the rear side seats.
3. Remo ...
Mazda 6 Owners Manual: Rear door speaker removal/installation
1. Disconnect the negative battery cable.
2. Remove the rear door trim.
3. Remove in the order indicated in the table.
4. Install in the reverse order of removal.
Rear Door Speaker Installation Note
Attach the speaker with the wiring harness placed in the groove of the door
unit panel.
...