CITROEN DS4 Owner's Handbook Manual page 281

Some functions are not available if the
battery is not sufficiently charged.
The batteries contain harmful substances
such as sulphuric acid and lead. They
must be disposed of in accordance
with regulations and must not, in any
circumstances, be discarded with household
waste.
Take used remote control batteries and
vehicle batteries to a special collection point.
It is advisable to disconnect the battery
if the vehicle is to be left unused for
more than one month.
Protect your eyes and face before
handling the battery.
All operations on the battery must be
carried out in a well ventilated area and
away from naked flames and sources
of sparks, so as to avoid the risk of
explosion or fire.
Do not try to charge a frozen battery;
the battery must first be thawed out to
avoid the risk of explosion. If the battery
has been frozen, before charging have
it checked by a CITROËN dealer or
a qualified workshop who will check
that the internal components have not
been damaged and the casing is not
cracked, which could cause a leak of
toxic and corrosive acid.
Do not reverse the polarity and use
only a 12 V charger.
Do not disconnect the terminals while
the engine is running.
Do not charge the batteries without
disconnecting the terminals first.
Wash your hands afterwards.
Practical information
Do not push the vehicle to start the
engine if you have an electronic or
automatic gearbox.
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