TM 5-3820-236-24-4
BATTERY
MT-23248
Figure 12a - Testing Specific Gravity
Stabilized Open Circuit Voltage Test
a.
If the battery has just been recharged or has
been in vehicle service, the surface charge must
be removed before an accurate voltage
measurement can be made.
To remove surface charge, crank engine for 15
seconds. DO NOT allow engine to start. To
prevent engine starting:
Gasoline Engine: Disconnect coil high tension
lead from distributor cap. Ground lead to
engine.
Diesel Engine: Apply engine stop control or dis-
connect fuel solenoid valve lead as required to
prevent engine start.
After cranking engine, allow battery to rest for 15
minutes.
b.
Connect voltmeter across battery terminals (Fig-
ure 12b) and observe reading. Compare reading
obtained with Table 4b to determine battery’s
state of charge.
c.
If stabilized voltage is above 12.4 volts, proceed
to Step 3.
MT-26010
Figure 12b - Voltmeter Connection for Stabilized
Open Circuit Voltage Test
TABLE 4b
Stabilized Open
Circuit Voltage
State of Charge
12.6 V or More
Fully Charged
12.4 V
75% Charged
12.2 V
50% Charged
12.0 V
25% Charged
11.7 V or Less
Discharged
d.
If stabilized voltage is below 12.4 volts, recharge
battery as instructed under CHARGING and
inspect vehicle’s electrical system to determine
cause for low state of charge. After charging
battery, proceed to Step 3.
Figure 12c - Relationship of Stabilized Open
Circuit Voltage to State of Charge
CTS-4111B -Page 11
