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: Replacing a Tire
WARNING
Always use tires that are in good condition: Driving with worn tires
is dangerous. Reduced braking, steering, and traction could result in an accident.
Replace all four tires at the same time: Replacing just one tire
is dangerous. It could cause poor handling and poor braking resulting ...
Mazda 6 Owners Manual: Fuel injector removal/installation
Caution
Disconnecting/connecting the quick release connector without
cleaning it may possibly cause damage to the fuel pipe and quick release
connector. Always clean the quick release connector joint area before
disconnecting/connecting using a cloth or soft brush, and make sure that it ...