The lights on my 99 500 Sportsman surge from bright to dim from time to time and I was wondering if someone here might have some idea why and what to check.

 

i would be checking the recifier(controls amount of voltage charging system puts out) make its not junk or maybe has corroded connections. its in front up under the by the radiaitor.

 

Is it possible to test the rectifier? I disconnected it and the connectors were clean.

 

Check voltage at battery with engine at about 3000 rpms,should be about 14-14.5 volts. If charging good and lights still flickers,could be battery beginning to go south on you! You can have it load tested at most auto supply companies. If charging not up to snuff, possibly reg/rectifier might need replacement.

 

you should get a voltage tester to see how much the system is putting out and when its surging. it will giv an idea if its too much voltage at least. there might be a way to check it if someone could look up the info in there manual.