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: Engine oil replacement
Warning
Hot engines and engine oil can cause severe burns. Turn off the
engine and wait until it and the engine oil has cooled.
A vehicle that is lifted but not securely supported on safety
stands is dangerous. It can slip or fall, causing death or serious injury.
Never work around or ...
Mazda 6 Owners Manual: Panel light control switch inspection
1. Connect the connector to the panel light control switch.
2. Connect the negative battery cable.
3. Measure the voltage at the panel light control switch using voltmeter.
When inspecting terminal B for continuity, disconnect the panel light
control switch connector.
4. If the value are ...