The manual shift mode gives you the feel of driving a manual transaxle vehicle by allowing you to operate the selector lever manually. This allows you to control engine rpm and torque to the drive wheels much like a manual transaxle when more control is desired.
To change to manual shift mode, shift the lever from D to M.

NOTE
Changing to manual shift mode while driving will not damage the transaxle.
To return to automatic shift mode, shift the lever from M to D.
NOTE
Active Adaptive Shift (AAS)
IndicatorsMazda 6 Owners Manual: Center panel module removal/installation
1. Cancel the anti-theft operation. (with anti-theft system) (See ANTI-THEFT
SYSTEM.)
2. Disconnect the negative battery cable.
3. Remove the glove compartment.
4. Remove the rear console.
5. Remove in the order indicated in the table.
6. Install in the reverse order of removal.
Caution
...
Mazda 6 Owners Manual: Automatic transaxle fluid (atf) replacement
Warning
When the transaxle and ATF are hot, they can badly burn you. Turn
off the engine and wait until they are cool before changing the ATF.
1. Remove the oil dipstick.
2. Remove the oil drain plug and washer.
3. Drain the ATF into a container.
4. Install a new washer and the drain ...