Mazda 6 Service Manual: No.20 noise occurs at idle when vehicle is stopped in all positions/ranges

No.19 excessive shift shock on torque converter clutch (tcc)

No.21 noise occurs at idle when vehicle is stopped in d, s, l ranges, or in r position

Other materials:

Mazda 6 Service Manual: Inspecting Electrolyte Level
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 sp ...

Mazda 6 Service Manual: Multi-Information Display and INFO Switch (Some models)
    The multi-information display indicates the following information. Odometer Trip meter Engine coolant temperature gauge Fuel gauge Outside temperature Distance-to-empty Average fuel economy Current fuel economy Maintenance Monitor ...