2012 Sportsman 400/500 and EFI Tractor Service Manual 9923412, Page 416Get this manual
ELECTRICAL Low Maintenance BatteryOCV- Open Circuit Voltage Test
Battery voltage should be checked with digital multitesterReadings of 12.8 volts or less require further battery testing and chargingSee charts and Load TestNOTE: Lead-acid batteries should be kept at or near full charge as possibleIf the battery is stored or used in partially charged condition, or with low electrolyte levels, hard crystal sulfation will form on the plates, reducing the efficiency and service life of the batteryNOTE: Use voltmeter or multimeter to test battery voltage
Low Maintenance Battery Load Test CAUTION
To prevent shock or component damage, remove spark plug high tension leads and connect securely to engine ground before proceedingNOTE: This test can only be performed on machines with electric startersThis test cannot be performed with an engine or starting system that is not working properlyA battery may indicate full charge condition in the OCV test and the specific gravity test, but still may not have the storage capacity necessary to properly function in the electrical systemFor this reason, battery capacity or load test should be conducted whenever poor battery performance is encounteredTo perform this test: 1Hook multitester to the battery in the same manner as was done in the OCV testThe reading should be 12.8 volts or greater2Engage the starter and observe the battery voltage while cranking the engineContinue the test for 15 seconds3During cranking the observed voltage should not drop below 9.5 volts4If the beginning voltage is 12.8 volts or higher and the cranking voltage drops below 9.5 volts during the test, replace the battery