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: Front oil seal
FRONT OIL SEAL REPLACEMENT
1. Disconnect the negative battery cable.
2. Remove the spark plugs. (See SPARK PLUG REMOVAL/INSTALLATION.)
3. Remove the Cylinder head cover. (See Cylinder Head Cover Installation
Note.)
4. Remove the drive belt. (See DRIVE BELT REPLACEMENT.)
5. Remove the front dr ...
Mazda 6 Owners Manual: Rear lateral link removal/installation
Caution
Performing the following procedures without first removing the ABS
wheel-speed sensor may possibly cause an open circuit in the harness if it
is pulled by mistake. Before performing the following procedures, remove the
ABS wheel-speed sensor (axle side) and fix it to an appropri ...