JLG X20JP - X600AJ Service Manual - Manual (Page 114)

SECTION 3 - CHASSIS & TURNTABLE
3-90 – JLG Lift – 3121623
Troubleshooting chart - electrical system
TROUBLESHOOTING AT THE BATTERY
Battery is
not being
charged
sufficiently
or at all, or
is being dis-
charged too
rapidly.
Battery is
overcharged.
Malfunction Indication Possible cause Remedial action
Poor connections, open
circuit or contact resist-
ance in charging circuit,
short-circuit in line.
Acid level too high. Draw off excess acid
with hygrometer. Acid emerging at
cell plugs.
Check voltage regulator,
renew if defective. Defective voltage regu-
lator.
Terminal voltage
permanently above
16.5 V at 12 V
nom inal voltage,
acid density above
1.285 kg/l,
battery acid boils. Charge voltage too high.
Battery capacity is too
low.
Check voltage regulator,
renew if necessary.
Install a larger-capacity
battery. As a temporary
measure, discharge the
battery at intervals, e.g.
by switching on con-
sumers without running
the engine.
Recharge the battery. Charging rate too low
(especially in winter).
Battery capacity too
large. Install a smaller battery.
Defective voltage regu-
lator (e.g. overheated/
overloaded). Renew the voltage re-
gulator.
Recharge battery at
low current (app. 1/40
of nom inal capacity
in Amps) for about 50
hours. (Only possible if
suplhatising not yet too
far advanced.) Other-
wise: renew battery. Battery capacity has
dropped severely due
to severe discharge for
a lengthy period (grey-
white coating on plates
(“sulphatising”).
Battery defective (inter-
nal short circuits). Renew the battery.
Even shortly after
charging, the ter-
minal voltage drops
rapidly to 7 V on
sys tems with 12 V
nominal voltage. Eliminate open circuit,
clean posts and clips,
tighten loose terminals.