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: Base removal
1. Remove the rearview mirror.
2. Wind each end of a wire around a bar.
Warning
Using a SST (piano wire) with bare hands can cause injury. Always
wear gloves when using a SST (piano wire).
Note
Use a long sawing action to spread the work over the whole length
of the SST (piano w ...
Mazda 6 Owners Manual: Keys
WARNING
Do not leave the key in your vehicle with children and keep them in a place
where your children will not find or play with them: Leaving children in a
vehicle with the key is dangerous. This could result in someone being badly injured
or even killed. Children may find these keys to be ...