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: Solenoid valve inspection
Resistance Inspection (On-Vehicle Inspection)
Caution
Water or foreign objects entering the connector can cause a poor
connection or corrosion. Be sure not to drop water or foreign objects on the
connector when disconnecting it.
1. Disconnect the negative battery cable.
2. Remove the ...
Mazda 6 Owners Manual: Center roof antenna removal/installation
1. Disconnect the negative battery cable.
2. Remove the headliner. (See HEADLINER REMOVAL/INSTALLATION.)
3. Remove in the order indicated in the table.
4. Install in the reverse order of removal.
5. After installation, verify that the rubber of the center roof antenna is
installed to the r ...