Dodge RAM TRUCK 1500 1995 Service Manual page 342

B R BATTERY/STARTING/CHARGING SYSTEMS DIAGNOSTICS
8A- 9
charging current (amperage) will be low. As the bat­
tery charges, the specific gravity of the electrolyte
will gradually rise.
CHARGING COMPLETELY DISCHARGED
BATTERY
The following procedure should be used to recharge
a completely discharged battery. Unless this proce­
dure is properly followed, a good battery may be
needlessly replaced.
(1) Measure voltage at battery posts with a voltme­
ter, accurate to 1/10 (0.10) volt (Fig. 10). If the read­
ing is below 10 volts, the charge current will be low.
It could take some time before the battery accepts a
current greater than a few milliamperes. Such low
current may not be detectable on ammeters built into
many chargers.
(2) Disconnect battery negative cable. Connect
charger leads. Some battery chargers are equipped
with polarity sensing circuitry. This circuitry protects
the charger and/or battery from being damaged if im­
properly connected. If the battery state-of-charge is
too low for the polarity sensing circuitry to detect,
the charger will not operate. This makes it appear
that the battery will not accept charging current. Re­
fer to the instructions provided with the battery
charger to bypass the polarity sensing circuitry.
(3) Battery chargers vary in the amount of voltage
and current they provide. The amount of time re­
quired for a battery to accept measurable charger
current at various voltages is shown in Charge Rate
chart. If charge current is still not measurable at end
of charging times, the battery should be replaced.' If
898A12
Fig. 10 Voltmeter Accurate to 1/10 Volt Connected
charge current is measurable during charging time,
the battery may be good and charging should be com­
pleted in the normal manner.
CHARGE RATE
Voltage Hours
16.0 volts maximum up to
4
hrs.
14.0 to 15.9 volts up to 8 hrs.
13.9 volts or less up to 16 hrs.
J928A-6