Searched and found it is a common problem. Wife boiled pasta and forgot to turn on exhaust fan. Microwave was soaking wet and problem began. Poor design on keypad allows moisture to enter. Could see moisture when old pad was removed. Probably could of took it apart and dried out.
Any how, part solved the problem. Be careful to remove all icky glue left over from old pad. Be careful when lining new pad up. One shot deal, when it sticks, it sticks. Also looks like I forgot to remove protective clear cover on display. Can see it once I stuck membrane on. Aint taking it apart for that.