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E. The battery must have a minimum 75% state of charge before being load
tested.
If battery state of charge is below 75%, load test results will NOT be accurate.
F. It is highly recommended that maintenance free batteries should be tested
with a voltmeter to determine state of charge.
Open Circuit
Voltage
OKAY to
{
12.60
t
12.40
Load Tes
12.20
{
DO Not
12.00
Load Test
11.80
OPEN CIRCUIT VOLTAGE TEST
A. Make sure load knob is in the OFF position.
B. Connect tester (+) Red lead to Battery (+) terminal.
C. Connect tester (-) Black lead to Battery (-) terminal.
D. If voltmeter reading is less than 12.4 volts, battery must be charged and
retested before continuing.
NOTE: If battery voltage is less than 12.4 volts after charging, replace the battery.
2. REMOVING THE SURFACE CHARGE
A. If your open circuit voltage reading is above 12.6 volts, remove the surface
charge before load testing. Failure to do so will result in inaccurate test
readings.
B. Three possible ways to remove a surface charge:
1. Turn headlights (high beam) on for 3 to 5 seconds.
2. Disable ignition: crank starter over for 10 to 15 seconds.
3. Using a variable carbon pile load tester, load battery for 10 to 15 seconds at
150 amp load.
connection is made or removed.
After removing surface charge, let battery stand for 10 minutes to stabilize.
3. CALCULATE THE LOAD
A. Look for either the "Cold Cranking Amps" CCA rating or the "Load Test Amps"
rating on the battery decal.
B. The load test amps rating should be on half (1/2) of the cold cranking amps
Approximate
State-of
Charge
100%
75%
50%
25%
0%
Make sure load knob is in the OFF position before
3
Average Cell
Specific
Gravity
1.255
}
OKAY to
1.225
Load Test
1.190
}
DO Not
1.155
Load Test
1.120
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