2005 Polaris Sportsman 400/500 Service Manual, Page 282Get this manual
ELECTRICAL
CHARGING SYSTEM TESTING FLOW CHART
Whenever charging system problems are suspected, proceed with the following system check after verifying that all wires are in good condition, connected and not kinked or pinchedUsing multitester set on D.Cvolts, measure the battery open circuit voltage (See earlier test)It should be 12.4 volts or moreIs it? Yes
Meter Setting: DC Volts
Remove the battery and properly serviceReinstall the fully charged battery or fully charged shop battery
With the transmission in Park, start the engine and increase RPM to between 3000 and 4000Read battery voltage with the multitesterReadings should increase to between 13.0 and 14.6 D.CAre they? No
Meter Setting: DC Amps
Check Key off Current Draw