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: Programming the HomeLink System
CAUTION
When programming a garage door opener or a gate, disconnect the power to these
devices before performing programming. Continuous operation of the devices could
damage the motor.
The HomeLink system provides 3 buttons which can be individually selected and
programmed using the transmi ...
Mazda 6 Owners Manual: Input/turbine speed sensor removal/installation
1. Disconnect the negative battery cable.
2. Remove the battery and battery tray.
3. Remove the air cleaner component. (See INTAKE-AIR SYSTEM
REMOVAL/INSTALLATION.)
4. Disconnect the input/turbine speed sensor connector.
5. Remove the input/turbine speed sensor.
6. Apply ATF to a new O-ring ...