A low level of electrolyte fluid will cause the battery to discharge quickly.

Inspect the electrolyte level at least once a week. If it is low, remove the caps and add enough distilled water to bring the level between the upper and lower level (illustration).
Do not overfill.
Examine the specific gravity of the electrolyte with a hydrometer, especially during cold weather. If it is low, recharge the battery.
Battery Maintenance
Battery RechargingMazda 6 Owners Manual: Side Air Bags
The side air bags are mounted in the outboard sides of the front seatbacks.
When the air bag crash sensors detect a side impact of greater than moderate
force, the system inflates the side air bag only on the side in which the vehicle
was hit. The side air bag inflates quickly to reduce injury ...
Mazda 6 Owners Manual: Front door removal/installation
1. Disconnect the negative battery cable.
2. To remove the front door hinge, remove the front fender panel.
3. To remove the checker, remove the door speaker.
4. Remove in the order indicated in the table.
5. Install in the reverse order of removal.
6. Adjust the front door. (See DOOR ADJUS ...