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: Front upper arm inspection
1. Remove the upper arm from the vehicle.
2. Inspect for damage, cracks, and bending.
3. Inspect the ball joint rotation torque.
(1) Rotate the ball joint five times.
(2) Measure the rotation torque using a suitable allen socket and a
torque wrench.
If not within the specification ...
Mazda 6 Owners Manual: Temporary Spare Tire
Inspect the temporary spare tire at least monthly to make sure it is properly
inflated and stored.
NOTE
The temporary spare tire condition gradually deteriorates even if it has not
been used.
The temporary spare tire is easier to handle because of its construction which
is lighter and small ...