State of Charge Test

Test Indicator Sight Glass:

USING TEST INDICATOR
The built-in test indicator (hydrometer) measures the specific gravity of the electrolyte. Specific gravity (SG) of the electrolyte will indicate state-of-charge (voltage); although, the test indicator will not indicate cranking capacity of the battery. Refer to Battery Load Test for more information. Look into the sight glass and note the color of the indicator, refer to the following description as color indicates:


GREEN - 75 to 100% state-of-charge
The battery is adequately charged for more testing or return to use. If the vehicle will not crank for a maximum 15 seconds, refer to Battery Load Test for more information.


BLACK OR DARK - 0 to 75% state-of-charge
The battery is inadequately charged and must be charged until green dot is visible (12.4 volts or greater) before the battery is tested or returned to use. Refer to Causes of Battery Discharging for more information.


YELLOW OR BRIGHT COLOR

WARNING: Do not attempt to charge, test, or assist boost battery when yellow or bright color dot is visible. Personal injury may occur.

A yellow or bright color dot indicates water (electrolyte) level in battery is below the test indicator. Water can not be added to a maintenance free battery. The battery must be replaced. A low electrolyte level may be caused by an over charging condition.