I installed an Alltrax in my E16 about 10 years ago and love it but recently, I've been hearing some moans and groans that sound like they are coming from the controller. This is typically heard when the loads increase around quarter throttle. At higher speeds, the noise is gone. Everything seems to work fine but it just said I don't recall ever hearing this before.

I had to replace the throttle pot about a month ago as the speed would jump around. It must've been worn out because I could tap on the lever arm while I was driving and the speed would change. Could those rapid changes in ohm readings have damaged the controller? But as I said, the tractor is working fine now with the exception of the noise. The wiring seems tight. 

I seem to recall a previous post regarding field voltage, and if that is out of whack, it can damage the controller. Does anyone know the procedure for checking field voltage?

Any thoughts is appreciated!

Thanks and have a great day.