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: Scheduled maintenance
SCHEDULED MAINTENANCE TABLE
For Europe (L.H.D. U.K.)
Chart symbols:
I : Inspect and repair, clean, adjust, or replace if necessary.
(Oil-permeated air cleaner elements cannot be cleaned using the air-blow
method.)
R : Replace
T : Tighten
L : Lubricate
Remarks:
To ensure efficient oper ...
Mazda 6 Owners Manual: Rear wiper motor inspection
1. Disconnect the negative battery cable.
2. Remove the liftgate lower trim. (See LIFTGATE LOWER TRIM
REMOVAL/INSTALLATION)
3. Disconnect the rear wiper motor connector.
4. Connect battery positive voltage to the rear wiper motor terminal A and
the ground to a bare metal part of the vehicle a ...