The answer boils down to whether or not the damaged key position's electrical contacts are still active, or, in other words, does the damaged key position still work when you press down on it. For example, if you press down on the "A" key position and you see a letter "A" or "a" registering the key position is still working. So, to test, open up an application such as your word processor and press down on the damaged key position. If the test fails, the whole keyboard needs replacing (our parts won't help you). If the test suceeds then our key parts can fix the damage.