Checking the battery charge (Opel Vectra B)

If, despite the normal acid level, the battery shows no signs of life, then you should check its charge status. Information about this can be obtained based on the specific gravity of the acid in the battery. With the Opel "Freedom" battery, it is enough to look into its inspection window. With batteries with a plug, you need a special hydrometer to perform the check, which you can rent at a gas station.

Unscrew the battery caps.

Suck out enough acid to ensure free floating of the hydrometer spindle.

Look at the specific gravity of the acid: 1.28 kg/l - the battery is fully charged; 1.20 kg/l - half charged; 1.12 kg/l - discharged.

Advice: if the acid density is uniformly low, it is enough to charge the battery. If individual cells are discharged, the battery is probably faulty - check it at a workshop that repairs automotive electrical equipment.