Checking the electrolyte
1. Make sure the electrolyte level is between the "UPPER" and "LOWER" marks.
If the level is below the "LOWER" mark, add distilled water. Do not fill completely.
2. Measure the density of the electrolyte using a hydrometer.
If the density of the electrolyte is less than the nominal value, charge the battery.
- Nominal density (at 20°C) — 1.27-1.29 g/cm³
[Full version on the source website «hondabook»]