New member here. I have done a bunch of searching around the forum and while I have found a few helpful suggestions, I still haven't been able to solve the issue I am having.

I have a 2008 Sportsman 500 that randomly won't start with the key anymore. I started it to plow the other day, drove around, turned the machine off for a couple of minutes, went to turn it back on and nothing. Not even a click at the solenoid. I pull started it and it worked fine. The interesting thing is the next day I tried using the key and it fired right up. But ever since that time, no luck with the key.

I have jumped the battery with no luck. Battery seems fine though as all lights turn on when I turn the key and the winch works fine. I jumped the solenoid and the machine fired right up. Tried replacing the solenoid and no change. I have also tried hitting the starter, but that didn't help at all. I pulled the headlight assembly apart and confirmed that all wiring was clean and installed correct at the key switch.

Any suggestions on what else to try at this point? I figured that since I can pull start the machine and jump it from the solenoid that it isn't an issue with the starter, but that's just a guess on my part. And I have confirmed that the machine is in neutral and run switch is on.

 

Pull the connectors from the left control switch,spray with electrical contact cleaner and use some electrical grease on the contacts. Same thing for the cracks and crevices in the switch and work the on/off emergency switch back and forth along with the other controls.. This control switch can cut power to the ignition switch,but with the the key on you can still recoil start it because it's a magneto triggered ignition and can crank with out the battery.Wouldn't advise taking the switch apart as spring and brass pieces can fly out.If a new one is needed you can find them here.Dirt Cheap Yamaha, Polaris, Suzuki & Kawasaki OEM Parts & Accessories – Cycle Parts Warehouse or on ebay.4011835 Polaris | eBay Another area that the 500 was bad about is over time the pick up coil can get weak or have trash on the it's face or on the flywheel magnetic strip that triggers a pulse to the cdi. Plus some pick up coils have been bent back from rope breakage and moving the bracket inward can help on electric starting once you get power back to the starter,etc.

 

Thanks for the info! I went ahead and cleaned up the control switch and unfortunately that didn't do the trick. I'm guessing that isn't the issue though as the on/off emergency switch seems to be working fine (display gauges only show up when in on position, not in off).

One thing I forgot to mention is that when I turn the key, it doesn't even try to turn over. No click at the solenoid or any other noise at all. Having said that, could it still be the coil that would be the issue?

 

Well then if the left control switch works ok,test the small power wire at the solenoid when you have the ign switch in the star position. Should have power to this wire. If not,the check the switch wiring. Not uncommon for ign switches to short out either. If you do have power on the solenoid trigger wire,but no click,etc,then probably the solenoid is faulty. You can find either one on ebay.

 

I have now replaced both the solenoid and the ignition switch and still no luck. Any other ideas out there?

 

Did you ever load test to the battery to see if it was the problem to begin with? It can show 12+ volts,but still may fail under a load because of a shorted cell.https://www.batterystuff.com/blog/ho...ry-is-bad.html If the battery checks out plus you've replaced the solenoid,checked ign and control switch,then the ecm can cause fits because of all the internal circuit breakers,controls that can fail or cause intermittent problems.http://www.ebay.com/itm/Polaris-2007...lWTg-Q&vxp=mtr

 

I've tried jumping the battery and that hasn't helped. Would it hurt anything if I tried a battery from my pull-behind mower? The battery is a little bigger in size, but not by much.

 

Again the ecm module it could be the cause. It does have a battery protection circuit in it that could be acting along with all the other things it controls such as charging,fan operation,etc. Before I threw any more parts at it I'd go through the trouble shooting guide in the manual that can help you trace down the electrical problem. Worth the 5 bucks. 2008 Polaris Sportsman 500 Service Manual PDF Download

 

Alright, new issue...I've tried running the ATV lately via pull start or jumping the solenoid. Today I jumped it from the solenoid and the machine completely cut off. No spark from the solenoid or anything. I swapped the solenoid out again with the one that was working before and nothing. I tried jumping the battery and then the machine would start, but as soon as I pulled the jumpers off, the machine would die. I tried throwing another battery on and then when I turn the key the fan turns on but nothing on the gauges. All four fuses look okay. Did I completely mess something else up?

 

No that we all know it's an efi not a carb model, start at the fuse block wiring as it was a common problem on wiring shorts. It can be lifted up and inspected for any loose wiring and corrosion on the pins that can cause intermittent problems. Delphi fuse blocks like this are cheap at auto stores,ebay,etc if needed. Per 080 029 036 4 ATO ATC Delphi Fuse Block Panel 4 Gang 12 V Blade Style Fuse | eBay Plus here's the cheap 5 buck efi manual that can help also starting at the electrical trouble shooting guides,schematic wiring diagram. No sense tearing into this machine blind and swapping out parts..2008 Polaris Sportsman 500 EFI Service Manual PDF Download