CITROËN C3 Handbook page 252

In the event of a breakdown
Charging the battery using a battery charger
For optimum service life of the battery, it is
essential to maintain an adequate state of
charge.
In some circumstances it may be necessary to
charge the battery:
- if you use your vehicle essentially for short
journeys,
- if the vehicle is to be taken off the road for
several weeks.
Contact a CITROËN dealer or a qualified
workshop.
If you envisage charging your vehicle's
battery yourself, use only a charger
compatible with lead-acid batteries of a
nominal voltage of 12 V.
If this label is present, it is essential
to use only a 12 V charger, to avoid
causing irreversible damage to the
electrical components related to the
Stop & Start system.
250
Follow the instructions for use provided
by the manufacturer of the charger.
Never reverse polarities.
It is not necessary to disconnect the
battery.
F Switch off the ignition.
F Switch off all electrical consumers (audio
system, lighting, wipers, ...).
F Switch off the charger B before connecting
the cables to the battery, so as to avoid any
dangerous sparks.
F Ensure that the charger cables are in good
condition.
F Raise the plastic cover, if your vehicle has
one, on the (+) terminal.
F Connect the charger B cables as follows:
- the positive (+) red cable to the (+)
terminal of the battery A,
- the negative (-) black cable to the earth
point C on the vehicle.
F At the end of the charging operation, switch
off the charger B before disconnecting the
cables from the battery A.
Never try to charge a frozen battery.
If the battery has been frozen, 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.