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: Tiedown Hooks (Some models)
CAUTION
Do not use the front and rear tiedown eyelets for towing the vehicle. They
have been designed only for securing the vehicle to a transport vessel during shipping.
Using the eyelets for any other purpose could result in the vehicle being damaged.
Tiedown Hooks
1. Remove the tiedown eye ...
Mazda 6 Owners Manual: Rear outer handle removal/installation
1. Remove the rear door glass.
2. Remove the rear door unit.
3. Remove the rear door latch.
4. Remove the bolts.
5. Detach the rear outer handle and rear door latch rod.
6. With the rear side of the rear outer handle fixed and the outer handle
lever pulled out (1), remove the rear side of t ...