Volkswagen Golf / Golf GTI / Jetta. Manual - part 1069

27-19

 

  

  

An insufficient electrolyte level allows the cell 
plates to dry, resulting in a loss of battery 
capacity (reduced output). If the cell plates are 
not completely submerged by electrolyte, 
(sulfuric acid/water mixture) corrosion will occur 
on the plates, plate bridges and cell connector. 
Optimum battery function is not possible under 
these conditions and battery failure results. 

  

  

If electrolyte level is too high, electrolyte (sulfuric 
acid/water mixture) may leak out and damage 
the surrounding area, i.e.: plenum and engine 
compartment.  

  

  

CAUTION!

 

  

  

Before beginning repairs on the electrical 
system

 

  

  

 

Switch off all electrical consumers.

 

  

  

 

Switch ignition off and remove ignition 
key.

 

  

  

-  Check electrolyte level visually, either via charge 

indicator (if equipped) or from min./max. 
markings on battery housing. 

     Electrolyte level reading from min./max. marking on 

battery housing -arrow-.  

If no minimum and maximum markings are visible 
on the battery housing (either not molded- in or not 
visible due to installation location) or if the battery 
housing is black, the sealing plugs must be 
removed. Then determine electrolyte level by 
viewing inside the battery cells.  

 Electrolyte level must be above the minimum 

marking or just reach the maximum marking.

Battery, checking

13/2/2005

27-20

 

  

  

-  First remove plastic foil from cell caps (where 

applicable), being sure not to disturb plastic 
safety warning label on battery. 

    

-  Unscrew cell caps -2-. 

-  Look into individual battery cells to determine 

electrolyte level. 

    

Note:  

On batteries with black housings, obtain accurate 
electrolyte level readings by illuminating inside of 
cells with a flashlight. 

Electrolyte level too low 

 

Page 27-21

   

Electrolyte level too high 

 

Page 27-22

   

 Electrolyte level must align with the internal 

electrolyte level indicator (lip) -1-. This equates 
to the external "maximum" marking on the 
battery case. 

Battery, checking

13/2/2005

27-21

 

  

  

Electrolyte level too low  

  

  

-  Fill with distilled water using battery filling bottle 

VAS 5045 (or equivalent) up to the max. 
marking 

  

  

Note:  

     Design of filler support on filling bottle VAS 5045 

prevents overfilling of battery cells and subsequent 
electrolyte leaks. When max. level is reached the 
flow of distilled water into battery cells stops. 

CAUTION!

 

Note:  

If it becomes necessary to top up the battery with 
distilled water, always perform battery test 
afterwards 

 

Page 27-30

 .  

 

Only use distilled water to top-up batteries. 
This prevents electrolyte impurities which 
cause self-discharging.

 

 

DO NOT overfill the battery

 

 

Overfilled batteries can boil over.

 

 

Too little electrolyte reduces the service life 
of the battery.

 

 

Use use of genuine VW battery cell caps 
ensures the different battery cover systems 
are sealed correctly. Only use genuine cell 
caps of the same construction if lost or 
damaged. All cell caps must be equipped 
with an O-ring seal.

 

Battery, checking

13/2/2005

27-22

 

  

  

Electrolyte level too high  

  

  

Special tools and auxiliary items 
needed  

    

WARNING!

 

 Commercially available 

hydrometer 

 

Refer to Warnings and Safety 
Measures 

 

Page 27-4

 . 

 

If electrolyte level is too high, 
electrolyte (sulfuric acid/water 
mixture) may leak out and 
damage the surrounding area, 
i.e.: plenum and engine 
compartment.

 

 

Excess electrolyte MUST be 
extracted using a hydrometer

 

 

Dispose of electrolyte (sulfuric 
acid) properly! Waste 
electrolyte must only be 
disposed of in appropriate 
waste disposal sites. Refer to 
local regulations pertaining to 
electrolyte disposal.

 

-  Remove cell caps from cells with 

excess electrolyte. 

    

CAUTION!

 

Use use of genuine VW battery 
cell caps ensures the different 
battery cover systems are sealed 
correctly. Only use genuine cell 
caps of the same construction if 
lost or damaged. All cell caps 
must be equipped with an O-ring 
seal.

 

-  Extract excess electrolyte using 

hydrometer until electrolyte level 
is lowered to internal level 
indicator -1- or external maximum 
marking. 

Battery, checking

13/2/2005