2005 polaris sportsman 700 efi. 4wd is always on. Indicator does not work with switch. Also, speedometer isn't working.

 

If it was electrical only then you loose power to the front diff as the ground path to the diff coil goes through the speedo.The awd switch can still work and light up,but with the ground path interrupted power wouldn't make it to the diff. Since the system is mechanically engaged also,a cracked roller cage or magnetized armature plate can keep the awd engaged/locked in whether the diff coil is receiving voltage or not.

 

If I have correct voltage to the awd coil, shouldn't the awd indicator come on when switch is on? Also, the speedo pointer goes down about 3 mm when i turn the key on, then goes back to 0 mph. Is that possibly a systems test to verify problem is not speedo but possibly the speed sensor?

 

If the speedo and mileage section is working,then the hall effect sensor on the caliper is working. If they're not then the sensor may have crapped out like others have done.This section still doesn't affect the awd. The way to see if the speedo awd ground path is in good shape is to make sure you use the ground wire directly at the diff along with the hot wire to test voltage.If you show voltage,then that part of the speedo is ok. If the awd indicator doesn't come on the speedo when key is on,in gear and awd switch engaged,then it could be an internal speedo problem itself. Main point I'm making is if you have the front wheels locked up,more than likely it's a mechanical problem. Even with voltage going to the diff the awd shouldn't engage unless the rear wheels loose traction and then unlock when the rear wheels regain traction or when you stop. Also switch the awd switch to off position. If the front wheels are still locked,then it's time to go into the diff. Cracked,damaged roller cages were the most common problem on this with magnetized armature plates second.

 

The speedo nor the odometer or trip odometer is working, so I guess the hall effect sensor is the easiest, cheapest thing to change. Is there a way to test that sensor without high tech equipment?

 

I made sure the sensor cup on the caliper bracket was clean of mud and dirt first just in case that blocked the signal for the speed and mileage.It got to be such a common thing on hall effect sensors shorting out that I didn't even bother with the test harness we had after the first few came through. I just grabbed a new one from the parts room.ONLY time I used the tester was if we were out of stock just to make sure before I ordered one. Always was the sensor when both the speed and mileage accumulation wasn't working.

 

That wouldn't make the 4WD stay locked in. If the diff has the right amount of the right fluid in it, then it's usually a cracked roller cage as OPT said. I don't know if they used the cheap plastic roller cage in that year and model or not. I think they did. If that's what it is and needs replacing, get a metal one instead of another cheap plastic one.

 

Polaris had aluminum roller cages listed as an"option or accessory" on almost all the atvs until after the 2014 models. Why they waited so long even though they knew about the problem on the plastic ones way before that. Pinching pennies..

 

I greatly appreciate the info OPT. I'm going to tear into it pretty soon and will let you know what I find. Probably going to try a new hall effect sensor first to get the speedo working correctly. And cool avatar btw!

 

That's the pic of a worn out mechanic..