Sportsman 400 4x4, model year 2001.

Just put a new battery in a month ago. Haven't run it for a couple weeks, went out to start it and got a very weak little turn, and I mean, VERY weak. Could barely hear the turn....

No lights working, etc. got her started by the pull rope and drove her around. Noticed even with it running, the lights were very very dim. Got her home and same thing, no lights, and unable to crank.

Here (to me) is where it gets strange. Pull the battery to put it on the charger, start her up with the pull rope again, and lights are nice and bright....what the heck is up with that?

Why is my battery being killed even when parked for a week, with the key out? And why would the lights not work with the the battery in while running, but take the battery out and the lights worked fine??

I think I have a short somewhere, but where to start looking.....

 

Battery tender is a good investment for machines that aren't ridden often. Check connections first for any corrosion or loose connections.Just because a battery is new doesn't mean that it can't be faulty. I've had bad ones straight out of the box that wouldn't hold a good charge. While running though, check that the charging system is ok,should be charging 14+ volts back to the battery. If the charging system is ok,have the battery load tested to tell if it has a dead cell. If the battery happens to test good,then you could have a parasitic draw that you'd have to track down.

 

Ok, so charge battery, left on my workbench, it kept the voltage fine for a week. So my impression is that it can hold a charge.

However, put it in the ATV, and two days later, it's down to 10.5v. Running the unit, I put the voltage meter on the battery, and it stays at 10.5. Seems like I am getting no charging from the unit. And I have some sort of "always on" that is slowly drawing the battery down.

Where should I start to look to see why I am getting no charging from the ATV?

 

opt will correct me if im wrong but if your bike isnt charging, that prolly killed the battery...and id look at the regulator? for that...

 

Just because a battery may show 12+ volts doesn't mean it's ok.12.5 volts on a battery is actually only 75% charged. A load test can tell real quick if a battery looses voltage and amperage under a load because of a dead cell. Plus 10.5 volts while running is too low,must show around 14 volts or more to keep one fully charged. This is more than likely the main problem. If it's been going on for awhile,it can cause a battery to sulfate quicker and not hold a charge. You could end up with two problems.. Charging and a battery that's constantly been run down. Again rule out the battery,plus check that all regulator wires are plugged in.May be simply a wire has come unplugged which was common on the Sportsman 400 and 500s.If they're hooked up,ohm the yellow wires leading from the stator to the regulator rectifier.There should be some resistance between each yellow with no yellow zeroing out to ground.This usually eliminates a stator charge coil from being the problem. If the stator checks out,then replace the regulator.This one replaces the Polaris #2205046 for your model.http://www.ebay.com/itm/NEW-RECTIFIE...9ViFFi&vxp=mtr Plus here's a good article on batteries in general. https://www.batterystuff.com/blog/ho...ry-is-bad.html Plus if you're not sure where the regulator is,it's up front by the radiator.