Battery sealing plugs

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On batteries with visible min and max markings, electrolyte level only needs to be checked visually.
Electrolyte level must be between min. and max. markings.
On batteries where the outer min. and max. markings are difficult to see or the visibility of the electrolyte level cannot be guaranteed due to the opaque battery housing, the sealing plugs must be removed. Then it is possible to check electrolyte level by a visual inspection of the battery interior.
The electrolyte level must meet the inner electrolyte level marking (plastic bar). This corresponds to the outer max. mark.

NOTE:

If electrolyte level is too low, battery loses capacity (loses performance) because the cell plates dry out. If the cell plates are not covered by electrolyte, the plates and plate bridges start to corrode causing the function of the battery to diminish. After a while the battery does no longer function. The battery becomes useless.

WARNING: If the electrolyte level is below them in. marking, the battery must be replaced! → - 27 BATTERY, STARTER, GENERATOR, CRUISE CONTROL