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Special tools and workshop equipment required
◆ Battery filler VAS 5045
◆ Commercially available hydrometer
Notes:
◆ The correct electrolyte level is an important factor in ensuring a long battery service life.
◆ On batteries with visiblemin. and max. marks, electrolyte level can be checked simply by visually inspecting
outside of battery.
◆ Electrolyte level must be above min. mark, but must not exceed max. mark.
◆ On batteries on which the outermin. and max. marks are difficult to see or proper checking of the electrolyte
level cannot be guaranteed on account of the opaque nature of the battery casing, the caps have to be
unscrewed. The electrolyte level can then be checked by way of a visual inspection of the inside of the
battery.
◆ The electrolyte level must coincide with the internal level mark (plastic web). This corresponds to the outer
max. mark.
◆ -> On batteries with a magic eye -arrow-, the electrolyte level can be established from the colour indicator.
◆ Test sequence => Page
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Electrolyte level too low
Note:
If the electrolyte level is too low, drying-out of the cell plates will reduce the capacity (power) of the battery. If
the cell plates are not surrounded by electrolyte, the plates, plate links and cell connectors will become corroded.
The function of the battery is then not guaranteed and it becomes unusable.
- -> If the electrolyte level is too low, use battery filler bottle VAS 5045 to top up distilled water as far as max.
mark.
Notes:
◆ The filler neck of the filler bottle VAS 5045 is designed to prevent over-filling of the battery cell and electrolyte
leakage. The flow of distilled water into the battery cell is interrupted on reaching the max. level.
Audi A3 1997 ➤
Electrical system - Edition 10.2003
1.9 - Checking electrolyte level
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