Electrical system, general information

Totally discharged batteries

~1min read

WARNING

Danger of injury! Observe warning notices and safety regulations → Chapter!

A battery is designated “totally discharged” when the no-load voltage is less than 11.6 V.
WARNING It is not permissible to test or charge batteries whose magic eye shows light yellow. Do not slave/jump start the vehicle!

Danger of explosion when checking and charging or slave/jump starting.

These batteries must be renewed.

Caution

Totally discharged batteries freeze prematurely.

Frozen batteries should no longer be used.

Note Totally discharged batteries in vehicles before registration must be exchanged prior to delivery. Preliminary damage cannot be excluded. Batteries that have not been used for a long period of time discharge themselves, e.g. those fitted in stored vehicles. In totally discharged batteries, the electrolyte is comprised almost entirely of water because the acid content is so low. Exhaustively discharged batteries sulphate, i.e. the entire plate surfaces of the battery harden. If a battery is recharged shortly after it has totally lost its charge, the sulphation will mostly dissipate. If these batteries are not recharged, the plates continue to harden and the ability to recharge is reduced. The result of which is a reduction in the battery output.
  • Check battery no-load voltage → Chapter.

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