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 Occupant Classification Sensor
Your vehicle is equipped with a front passenger occupant classification sensor
as a part of the supplemental restraint system. This sensor is equipped in the front
passenger's seat cushion. This sensor measures the electrostatic capacity of the
front passenger's seat. The SAS unit is designed ...
Mazda 6 Owners Manual: Setting the System
When the MODE switch is pressed, the Mazda Radar Cruise Control (MRCC) main indication
(white) turns on and the vehicle speed and the distance between vehicles while in
headway control can be set.
NOTE
When the ignition is switched to ACC or OFF while the Mazda Radar Cruise
Control (MR ...