The membrane key unit is available for most recent models. You peel off the old one and stick on the new one.
In some cases, you may have to order the control panel frame with keypad.
You can order parts for Sharp models from Tritronics at http://www.wehaveparts.com.
You can find wiring diagrams and parts lists and order parts for most other brands from the Pros here: http://tinyurl.com/gv383.
In my professional opinion, no one should work on a microwave unless they are fully informed and aware of the deadly hazards and necessary precautions.
You can find this information and in our safety and disassembly text files at http://www.microwavedisplay.com
William Miller † MicrowaveDisplay.com, March 2007
