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: Cruise actuator removal/installation
1. Disconnect the negative battery cable.
2. Remove in the order indicated in the table.
3. Install in the reverse order of removal.
Cover Removal Note
Unclamp the clips of the heater hoses at the front of the cover.
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Mazda 6 Owners Manual: Locking, Unlocking with Door- Lock Knob
Operation from inside
To lock any door from the inside, press the door-lock knob.
To unlock, pull it outward. This does not operate the other door locks.
NOTE
The red indication can be seen when the door-lock knob is unlocked.
Operation from outside
To lock the rear and front passenger doo ...