So this is the second time this happened to me now. I purchased this 4 wheeler over the summer and it has run great. Over the summer I used 4wd one time to pull a stump and it worked fine. The first snow we had I had it in 2wd and was running around. I got stuck trying to go up a hill so I turned on the 4wd. When I hit the throttle the rear tires would just spin but the front tires did nothing.

The second snow we had was much different. I put it in 4wd before I even went out and I had no problems in the snow at all.

Then today we got more snow. I put it in 4wd and went out. Got about 5 feet out of the driveway and got stuck. The rear tires would just spin but the front tires did nothing.

I don't even know where to start looking. i make sure the plug going into the throttle area (where the 4wd button is) was plugged in tight and it was.

Any help would be appreciated.

 

When my AWD starts getting a mind of its own I find a fresh hub fluid change straightens it out.
Here is a video on it if you do not know how.
Only thing is I use the fill hole to both drain and fill ,I don't take the hub cap off. But this guys way is not bad since he gets a rag in there to help clean as well.

Clean and proper fluid level is important on this Awd set up I find.

 

Always change fluid first as TLC mentioned,but if both front wheels wont turn it may be something other than fluid. Usually just one side at a time will act up,not both at the same time. Plus does the speedo work,awd indicator light up? If not could be a loss of awd ground that runs through the speedo. You can jump the brown/white wire in the speedo harness to the brown wire or another good ground and see if the front wheels turn while up against a post or tree.Plus the same thing can happen if you lose ground on the small brown wires at the hubs. Probably can do the same reground as this guy on a Sportman 500 did.

 

It is funny you mention the speedo. It actually does NOT work. The neutral, reverse etc. lights work fine and the backlight lights up (I think), but the actual speedo and hour/miles counter does NOT work.

I will have to take a look at the ground thing. When I bought the quad the previous owner did a full fluid change (an gave me the left over fluid). I have a bottle of the hub oil (Polaris brand). So just to be on the safe side I think I will change the hub fluid, but I will also take a look at the ground thing too. I wonder if this might fix my speedo!

I love this forum! Hope I can get it all fixed up now.

 

So I changed the front hub fluid. It was pretty clean and full to the proper level, but I guess it never hurts to do it. It did not fix anything.

So I took off the front hood. There was a single yellow wire with red stripe that was flopping around disconnected. I found where it connected and plugged it in. I then fired it up and the 4wd worked flawlessly.

So just for my own sanity I wanted to verify that it was that wire that fixed the problem and not just me messing around in there. I disconnected that yellow wire with the red stripe again and the 4wd still worked fine. So I am thinking its the grounding issue. I will do that splicing thing mentioned in the video above.

I guess my next question is does anyone know what the yellow wire with the red stripe goes to? Am wondering why it was disconnected.

Also there is a brown wire with a female spade end on it that is disconnected coming out of the little black box that the guy in the video above shows. Not sure where that is supposed to connect.

 

The yellow/red possibly came from the speed limiter or the regulator harness as it affects the awd system.It's main purpose is to keep awd from engaging past a certain speed/rpm to prevent damage. If unhooked,could stop awd from engaging.Item #32,37 Dirt Cheap Yamaha & Polaris OEM Parts & Accessories – Cycle Parts Warehouse Most likely the reason for no speed or mileage accumulation is the hall effect sensor on the right front caliper has shorted out.Common thing for this to happen. You can check for any dirt/mud blockage,but if it's clean I'd just replace the sensor to regain the speed and mileage function on the speedo. Item#38.Dirt Cheap Yamaha & Polaris OEM Parts & Accessories – Cycle Parts Warehouse As far as extra wires,you may have an unused brown(ground) along with a red/white wire that's for hooking up optional equipment.

 

Well I went and did the ground wire fix. Also cleaned the sensor for the speedo.

The 4wd is working as expected. The speedo still doesn't work though. I will just replace the sensor when spring comes around. It isn't really important to me right now.

Everything was spot on though. That yellow wire with the red stripe went exactly where you said it did. I plugged that back in. No reason that should be disconnected anyway.

Appreciate all the help! Time will tell if the ground wire change fixes it completely.

 

Just pull it up to a tree or post and test if the front wheel kicks in ok. Some people have even pulled the hall effect sensor plug at the speedo to hide their true mileage.. Had a few shady customers do that. Sounds like you have it going your way.

 

I am pretty sure the plug at the speedo is plugged in. I saw a plug going in when I looked before. I can double check though.

I had all 4 wheels jacked up when I was testing it out. Everything worked as was stated. The front wheels kicked in within an 1/8th of a turn. Then when I turned it off after a sec then stopped. Would assume they stop sooner when there is a load on the front wheels.

Thanks once again for your help!

 

Now that the 4WD is working you should know to NEVER engage it while the rear wheels are spinning.