If one or more of the keys are not responding when you press them, it may need a new keypad, or it may just be that the connections need cleaning.
On some of these models, the display and keypad are connected to the circuit board via a conductive rubber zebra strip.
Sometimes steam (or spray cleaners!) can get in there and interfere with conductivity for the keys and/or display.
One would have to take it apart and clean the connections with high-grade alcohol, like 70% or better isopropyl from the drug store.
The attached photo is similar but not the same model.
If the keypad has been damaged or a cleaning does not do it, you will need a new keypad, and disassembly can be a bit tricky.
You can find
links to helpful exploded view diagrams and part ordering help
here.
I'd recommend that your bookmark this link to your favorites.We
regularly repair these control units for customers nationwide by
mail for $39.95 postpaid in about a week or so with a one-year
guarantee.We're
happy to help you with free advice and we'd appreciate your thoughtful
rating of our answer.William E. Miller[email protected]http://www.microwavedisplay.com