Yeah I'll have to find somewhere to help on what gets power and what doesn't on that connector plug for speedometer. Probably should start with the ground for it. Read on a few sites of people losing a ground and it'd kill the power to it.
Anyway to take the speedometer apart to check it?

 

http://forums.atvconnection.com/pola...ml#post3232409 KA7OEI's blog: Repair of the speedometer on a Polaris Sportsman 500 4-wheeler

 

I just chased a similar issue. Here's wht I did.
I put a new ecm in it, worked for a little bit.
Pretty sure stator was overcharging, and fried new ecm.
Got new ecm,under warranty, replaced stator, and went to start. No power whatsoever.
Replaced keyed switch, nothing.
Took kill/headlight switch apart. Bad idea, as tiny little parts went flying everywhere.
Decided this was out of my hands, and was going to take it to my guy. I had bought another kill switch, so that he didn't have to mess with that. I put it on, and turned the key, and it fired right up.
You can pick up a used kill switch for around $30. Just look for one in good, working condition.
I would also open up, or at.least drain the recoil cover. I have heard that machines that have sat outside a lot, tend to get quite a bit of water through the pull start handle, and screw with the stator.
If you need a new ecm, you can get them off eBay, for $150, with a 90 day warranty.
Super long post, but hope it helps.

 

One of the most over looked parts that can cause a lot of frustration.With all the functions the left control switch handles,on/off switch,reverse over ride, speedo toggling, low/high beam light controls,yes they can cause problems but some parts of the switch may still work and people may think that they're still ok. Even a simple thing as the pins not making good contact on the two plug in connectors can cause problems. You can't tear them apart and hope to be able to put them back together right,at least I never could.I've had to replace a bunch of these over the years myself that were faulty after checking out everything else.

 

Exactly. One of the pins was pretty green, so I would have to think that is where my issue was.