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: Troubleshooting procedure
Basic flow of troubleshooting
DTC troubleshooting flow (on-board diagnostic)
Diagnostic trouble codes (DTCs) are important hints for repairing
malfunctions that are difficult to simulate.
Perform the specific DTC diagnostic inspection to quickly and accurately
diagnose the malfunction.
The ...
Mazda 6 Owners Manual: Refrigerant pressure switch removal/installation
1. Remove the battery.
2. Discharge the refrigerant from the system. (See RECOVERY.) (See CHARGING.)
3. Loosen the refrigerant pressure switch using two spanners.
4. Remove in the order indicated in the table.
5. Install in the reverse order of removal.
Refrigerant Pressure Switch Installat ...