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: Fuel-Filler Lid and Cap
WARNING
When removing the fuel-filler cap, loosen the cap slightly and wait for
any hissing to stop, then remove it: Fuel spray is dangerous. Fuel can burn
skin and eyes and cause illness if ingested. Fuel spray is released when there is
pressure in the fuel tank and the fuel-filler cap is re ...
Mazda 6 Owners Manual: Power window motor removal/installation
1. Disconnect the negative battery cable.
2. Remove the front door trim or rear door trim.
3. Disconnect the power window motor connector.
4. Remove the bolts.
5. Remove the power window motor from the power window regulator drum.
6. Install in the reverse order of removal.
Note
When ins ...