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: Operating Tips for CD Player
Condensation phenomenon
Immediately after turning on the heater when the vehicle is cold, the CD or optical
components (prism and lens) in the CD player may become clouded with condensation.
At this time, the CD will eject immediately when placed in the unit. A clouded CD
can be corrected sim ...
Mazda 6 Owners Manual: No.2 neither abs warning light nor brake system warning lightilluminate with
ignition switch on
When performing an asterisked (*) troubleshooting inspection, shake the
wiring harness and connectors while doing the inspection to discover whether
poor contact points are the cause of any intermittent malfunction. If there
is a problem, check to make sure connectors, terminals and ...