Sir, Take a look at the voltage that is coming out of your regulator/rectifier. It should be about 14.5VDC with the engine running. If the voltage is higher, replace your rectifier/regulator.

Also, take a look at the voltage on the angle sensor. It should be 5VDC. If it is higher, then you may need a new ECM (computer).

Also...look at this thread as this guy is having a similar problem as you are: http://www.hondaatvforums.net/forums/repair-maintenance/40256-07-420-rancher-es-problems.html

 

Hondarubicon, I just went through this also and nearly pulled my hair put trying to figure out why the new sensor I had just replaced went bad so quick and it could be something as simple as the plug not getting plugged in very tight when you replaced it and some new riding time vibrated it loose which was my situation. Check the simple things first because if the codes you are reading indeed tell you that you have a bad sensor then that should be your problem and just as Kentco said you do have to have a good charged battery. Your manual will run you through all of the steps which I am sure you know you can get from this forum. Good luck.

 

3rd sensor now all went bad the regulator is good first sensor went from water second from snow im guessing this one got snow under it to