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: Transaxle range (tr) switch removal/installation
1. Disconnect the negative battery cable.
2. Remove the air cleaner component. (See INTAKE-AIR SYSTEM
REMOVAL/INSTALLATION.)
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 w ...
Mazda 6 Owners Manual: Master cylinder disassembly/assembly
Caution
If the master cylinder body is damaged, replace the unit as a
component. When securing the master cylinder in a vise, tighten only the
flange of the master cylinder.
1. Disassemble in the order indicated in the table.
2. Assemble in the reverse order of disassembly.
Stop ...