All doors lock automatically when the lock side is pressed. They unlock when the unlock side is pressed.
Driver's door

Front passenger's door

To lock all the doors from an open front door, press the lock side of the door lock switch and then close the door.
NOTE
When locking the doors this way, be careful not to leave the key inside the vehicle.
Locking, Unlocking with Transmitter
Auto Lock/Unlock FunctionMazda 6 Owners Manual: Engine Start Function When Key Battery is Dead
CAUTION
When starting the engine by holding the transmitter over the push button start
due to a dead key battery or a malfunctioning key, be careful not to allow the following,
otherwise the signal from the key will not be received correctly and the engine
may not start.
Metal parts of ot ...
Mazda 6 Owners Manual: Instrument cluster configuration
1. Connect the SST (WDS or equivalent) to the DLC-2.
2. Input vehicle information following the directions on the screen.
3. Select Module programming.
4. Select Programmable module installation.
5. Select the following items and perform procedures according to directions
on the screen.
...