Magnadyne keyless entry

We have the Magnadyne keyless entry on our 2010 Thor Monticeto RV, it worked on and off for the last couple of months, then completely stopped working. Yesterday, I inserted the door key turned it and it started making a loud almost grinding noise after a couple of seconds it stopped. I took the keyless and door components apart now no noise and it still doesn't work. Any idea's? You have all been a great help in the past, so I will thank you now for any help!
Firedog