Battery - Porsche 928 GTS 1994 Owner's Manual

Battery

The battery is located underneath the collapsible
spare tire in the luggage compartment. The
battery is accessible after taking out the spare
tire.
Only use an original Porsche battery, with the
correct part number, as a replacement.
Before work is done on the electrical sys-
tem, the battery must be disconnected to
prevent short circuiting. First disconnect
the negative ground wire at body (arrow)
98
and then the positive cable. To reconnect
battery, reverse the procedure.
This precaution must also be taken before
charging with a rapid charger, as the alter-
nator may otherwise be damaged.
Disconnecting the battery while the engine
is running will damage the alternator. This
also applies to cars equipped with a battery
main switch.
Never drive the car with a disconnected
battery as this will damage the alternator.
If the battery is disconnected, the data for the
engine electronics stored in the control unit are
erased. When the battery is reconnected, the
engine should be run for approx. 10 minutes to
allow the control unit to re-acquire these data.
During this period, the engine may idle unevenly
or too fast.
Curtail unnecessary power consumption,
particularly in city traffic or when travelling
short distances only.
WARNING
Do not lay tools or other metal objects on
the battery as they could cause a short cir-
cuit across the battery terminals.
Do not expose the battery to an open flame
or electric spark. Hydrogen gas generated
by the battery is explosive.
Do not let battery acid come in contact with
skin, eyes, fabric or painted surfaces.
If you get electrolyte, which is an acid, in
your eyes or on skin, immediately rinse with
cold water several minutes and call a doctor.
Spilled electrolyte must be rinsed off at once
with a solution of water and baking soda to
neutralize the acid and prevent damage to
fabric and metal.
Checking the electrolyte fluid level
The electrolyte fluid level in your battery can be
checked by unscrewing and opening the filler
vent caps of each cell. The fluid level should
meet the indicator mark in each cell. If neces-
sary, top off with distilled water.
How often water must be added depends on
operating conditions and on the time of year.
Generally, the electrolyte level must be checked
more often in the summer than in the winter,
and more often when driving long distances.
Only fill up to mark, otherwise the electrolyte will
overflow when the battery is being charged and
cause damage.