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: Add-On Non-Genuine Parts and Accessories
Non-genuine parts and accessories for Mazda vehicles can be found in stores.
These may fit your vehicle, but they are not approved by Mazda for use with Mazda
vehicles. When you install non-genuine parts or accessories, they could affect your
vehicle's performance or safety systems; the Mazda w ...
Mazda 6 Owners Manual: Outside Temperature Display
When the ignition is switched ON, the outside temperature is displayed.
NOTE
Under the following conditions, the outside temperature display may differ
from the actual outside temperature depending on the surroundings and vehicle conditions:
Significantly cold or hot temperatures.
Sudden ...