Checking electrolyte level (batteries with condition indicator) — VW

Special tools, testers, measuring units and auxiliary items required

VAS 5045 Battery filling bottle

Warning!
When using sulphuric acid it is absolutely necessary to adhere to the accident prevention procedures.
Suitable protective clothing must be worn.
Only use a torch to illuminate the inside of the battery housing.
Never illuminate the inside of a battery housing with an open flame.
Never work with an open flame or burning cigarette in the vicinity of a battery.
Ensure the legislation for the disposal of batteries and sulphuric acid is observed when disposing batteries.
Note:

The electrolyte level can be read at the condition indicator -arrow-.
If the colour indicator is colourless or yellow, it is absolutely necessary to top up distilled water.

A correct electrolyte level in the battery is an important factor in ensuring a long battery service life.

An insufficient electrolyte level allows the battery plates to dry which results in a loss of capacity (reduced output) of the battery. If the cell plates are not covered by electrolyte the plates, the plate bridges and the cell connections will corrode. This corrosion ensures the battery function can no longer be guaranteed. The battery is unusable.

If the electrolyte level is too high, damage will be caused outside the battery by the leaking battery acid (sulphuric acid/water mixture) e.g. components in engine compartment.

Notes:

If the electrolyte level is low, the filler bottle VAS 5045 is the ideal tool to top-up the battery. The design of the filler nozzle prevents any spilling or over filling. Once the maximum fill level has been reached, further filling of the battery is prevented due to the special nozzle feature of the filler bottle VAS 5045.
Use distilled water only, this prevents contamination of the battery electrolyte and the therefore associated increased self discharge.
If, for technical reasons, batteries are equipped with cell plugs, these are covered with a plastic foil.
If in place of a cell plug a condition indicator is fitted, this obviously will not be covered.

If the electrolyte level is not OK, correct as follows:
Remove battery cell plug.
If the electrolyte level is too low, fill with distilled water using only the battery filling bottle VAS 5045 up to the max. marking. The battery filling bottle VAS 5045 is the ideal tool for this purpose.

Note:

If you had to top up distilled water, again perform a battery discharge test.

Battery discharge test =>Page
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