Depress the button on the seat belt buckle. If the belt does not fully retract, pull it out and check for kinks or twists. Then make sure it remains untwisted as it retracts.

NOTE
If a belt does not fully retract, inspect it for kinks and twists. If it is still not retracting properly, have it inspected at an Authorized Mazda Dealer.
Fastening the Seat Belt
Front Shoulder Belt AdjusterMazda 6 Owners Manual: Seat Warmer (Some models)
The front seats are electrically heated. The ignition must be switched ON.
Press the seat warmer switch while the ignition is switched ON to operate the
seat warmer. The indicator lights turn on to indicate that the seat warmer is operating.
The mode changes as follows each time the seat warmer ...
Mazda 6 Owners Manual: Manual Shift Mode
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 ...