This thread was dead since the 25th of last month so I knew Chaddy wouldn't see this good info that may help him.
If irritating to see, my apologies.

BTW, I'm posting in the Polaris Forum Normal Threads, not the "Expert Section". (Ref: Quote from March 2012 https://atvconnection.com/forums/pol...cate-post.html )

 

Might try to ride on Saturday at same location that I had the issue the first time. My father in law has an 850 XP that is 2 years old now. Sits on a tender like mine. I will try to swap batteries to see if that will change the condition. If I have a chance to do it, I will post my findings.

I am eager to put to rest pocket's concerns over a battery that has more than 3 years of age.

 

Too warm out to fully know if the battery made a difference at this point. Was above freezing the whole time so everything worked as it has since issue began. Did have PS light to come on, and the check engine light came on the gauge cluster once while riding. Drove 2 feet and it cleared. Other than that, no issues.

Had to say, it was a blast playing in the snow!

 

I am here to report that a new battery DID NOT resolve my issue. Steering is locked up just like it was prior in freezing conditions. The sales guy at Batteries Plus who is very into ATV's even thought I was crazy replacing a perfectly good battery (that he ran tests on as well).

Again, a new battery DID NOT resolve my issue.

 

Didn't think a new battery would help. Still sounds like moisture in cold weather gumming up the works. Don't know if you feel like doing it,but you can still remove the unit and pop it open in perhaps a chance to see what might be causing it to lock up. Either moisture in the motor brushes,armature or even in the gears in the main gear box would be my guess. It's got to be something simple if it works perfectly when warm.Just a thought again on this.

 

I think the next step for me will to bite the bullet and take it to my dealer and just pay them to do a diagnostic on it. If it displayed the check engine light last time I rode, it should be something that they can pull on their computer at the shop, correct? Spending $50-$100 to get to the real answer might be worth my time and money on this issue at this point.

I really appreciate all your time on this subject OPT. If I have any further developments I will be sure to post it.

 

Then by all means if it showed the check engine light and the battery is new,I'd let Digital Wrench trace down what could be causing the code. Hope fully something simple that can solve the eps problem.

 

Not sure if yours is the same as a 850 , here's one from another forum , check the last couple of posts .
09 850 XP Power steering quits working.... - Polaris ATV Forum

 

This is what it looks like inside -
Polaris 850 XP EPS system disassembly - Polaris ATV Forum

 

Good breakdown pics on the eps. Just what they need,a little moisture,plastic gears and circuit boards to gum up the works..Just repaired a washing machine that the agitating gear was made out of plastic. Saw this post also.http://www.polarisatvforums.com/foru...tml#post216871 Never like o-rings on something like this. Same thing that would happen on the water craft. O-rings around the pump housings would leak air causing cavitation and would either sound like gear grinding or in worst cases heat/air would eat holes even in stainless steel impellers. Better sealing of the eps units might solve all of this if manufactures would pay heed.