174n
BatteryDo not short circuit the battery termi-
nals. This creates a risk of personal in-
jury from high-voltage sparks.
A highly-explosive gas is
generated when the battery is
charged.
If you happen to get acid in
your eyes, rinse thoroughly for
15 minutes with clear water.
Consult a physician immediately. If you
get acid spray on your skin or clothing,
rinse with plenty of water. If electrolyte
is accidentally ingested, consult a phy-
sician immediately.
In order to protect the battery
case from ultraviolet radiation,
do not place it in direct sunlight.
A discharged battery can freeze. Store
the battery in areas where temperature
remains above freezing.Car careThe battery is completely maintenance-
free, that is, the original electrolyte will
normally last for the service life of the
battery.
Charge condition – BMW 740i/LYou can read the charge condition of
the battery with the "Magic Eye" (a hy-
drometer) (not released at this time):
>Green: Adequate charge
>Black: Not charged adequately. The
battery must be recharged. Please
contact your BMW center
>Yellow: Replace the battery.380de655
Charging the batteryCharge the battery in the vehicle only
when the engine is off. Charge the bat-
tery using the supplementary positive
terminal and ground (terminal) in the en-
gine compartment (refer to "Jump-start-
ing" on page 179).
On the BMW 750iL, there is an auto-
matic switch between the two batteries
during charging.
Before performing any work on
the electrical system, disconnect
the cable from the negative terminal. If
you do not, short circuits can create the
risk of fire or personal injury.
If a jump start is necessary, connect the
cables only to the auxiliary terminal for
jump starting and a ground in the en-
gine compartment in order to avoid
damage to the batteries (refer to
"Jump-starting" on page 179).<
179n
RepairsIndexOverview Controls Car care Technology Data
Jump-startingNever use spray starter fluids to start
the engine.
If the battery is discharged, you can use
two jumper cables to start your car with
power from the battery of a second ve-
hicle. Always use jumper cables with
fully insulated handles on the terminal
clamps.
Do not touch high-voltage wiring
and cables on a running engine.
There is a risk of fatal injury if you do
this.<
Carefully comply with the following in-
structions to avoid personal injury and
damage to one or both vehicles:
1 Ensure that the battery on the sup-
port vehicle is also rated at 12 volts,
and that the capacities of the two
batteries (Ah) are roughly comparable
(printed on casing)
2 Leave your battery connected to the
car electrical system
3 Make sure that there is no contact
between the bodywork of the two ve-
hicles – short circuit risk.
4 Start by connecting the jumper cable
from the positive terminal of the sup-
port vehicle to the positive terminal
connector located in your BMW's en-
gine compartment. The cover of the
auxiliary terminal for jump starting is
marked with "Batt. +" (refer to the il-
lustration). Remove by pulling tab.
The illustration shows the auxiliary
terminal for jump starting the BMW
740i/L as an example. For the BMW
750iL: Refer to "Engine compart-
ment" on page 140380de089
5 Then connect the negative terminals.
Attach the cable to either the support
vehicle's negative battery terminal,
or to a suitable ground on its engine
or bodywork. Then connect the other
end of the cable to ground on the ve-
hicle's engine or bodywork which is
to be started. Then connect the other
end of the cable to a ground on your
vehicle's engine or bodywork (for in-
stance, the nuts on the strut dome.
Refer to the arrows in the illustration
above)
Follow the same sequence for
connecting the jumper cables if
you assist in jump-starting another ve-
hicle. If you do not, there is a risk of in-
jury caused by spark generation at the
battery.< 380de117