The rear armrest in the center of the rear seatback can be used (no occupant in the center seat) or placed upright.

WARNING
Never put your hands and fingers around the moving parts of the seat and armrest:
Putting your hands and fingers around the moving parts of the seat and armrest is dangerous as they could get injured.
Split Folding
Head RestraintsMazda 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: Hold switch removal/installation
1. Disconnect the negative battery cable.
2. Remove the console.
3. Disconnect the connector and remove the HOLD switch terminals. (See
SELECTOR LEVER DISASSEMBLY/ASSEMBLY.)
4. Remove the selector lever knob component.
5. Remove the HOLD switch.
6. Install the HOLD switch to selector lever k ...