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: Audio control switch removal/installation
Note
The audio control switch and the cruise control switch use a
common connector.
1. Disconnect the negative battery cable.
2. Remove the driver-side air bag module. (See DRIVER-SIDE AIR BAG MODULE
REMOVAL/INSTALLATION.)
3. Remove the steering wheel.
4. Remove in the order indicated ...
Mazda 6 Owners Manual: Engine coolant
ENGINE COOLANT LEVEL INSPECTION
Verify that the coolant level in the coolant reservoir is between the F and L
marks.
If the engine coolant level is below L, remove the radiator cap and add
coolant. (See COOLING SYSTEM SERVICE WARNINGS.)
ENGINE COOLANT REPLACEMENT
Warning
Drain the ...