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: HomeLink Wireless Control System (Some models)
NOTE
HomeLink and HomeLink house icon are registered trademarks of Gentex Corporation.
The HomeLink system replaces up to 3 hand-held transmitters with a single built-in
component in the auto-dimming mirror. Pressing the HomeLink button on the auto-dimming
mirror activates garage doors, gates ...
Mazda 6 Owners Manual: Purge solenoid valve removal/installation
1. Disconnect the negative battery cable.
2. Remove in the order indicated in the table.
3. Install in the reverse order of removal.
Vacuum Hose Installation Note
Attach the vacuum hose onto the purge solenoid valve until it contacts the
stopper.
Evaporative Hose Installation Note
Attach ...