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 passenger air bag deactivation indicator light
This indicator light turns on to remind you that the front passenger front and side air bags and seat belt pretensioner will not deploy during a collision.
If the front passenger occupant classification sensor is normal, the indicator light turns on when the ignition is switched ON. The ...
Mazda 6 Owners Manual: Rear lateral link removal/installation
Caution
Performing the following procedures without first removing the ABS
wheel-speed sensor may possibly cause an open circuit in the harness if it
is pulled by mistake. Before performing the following procedures, remove the
ABS wheel-speed sensor (axle side) and fix it to an appropri ...