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: System Operation
Make sure that the Lane-keep Assist System (LAS) & Lane Departure Warning System
(LDWS) OFF indicator light in the instrument cluster is turned off. When the Lane-keep
Assist System (LAS) & Lane Departure Warning System (LDWS) OFF indicator light is
turned on, press the switch and make ...
Mazda 6 Owners Manual: Active Driving Display (Some models)
WARNING
Always adjust the display brightness and position with the vehicle stopped:
Adjusting the display brightness and position while driving the vehicle is dangerous
as doing so could distract your attention from the road ahead and lead to an accident.
CAUTION
Do not try to adjust the ...