Due to the usage of certain
keys and environmental factors, the membrane keypad may become faulty,
and a key may become stuck. When that occurs, all other keys become
non-working. To test the keys, start with the F1
and push each key down and then release. You should see the key down
identified and also the release or key up. Continue for all of the
F keys, all of the numbers,
the left and right arrows, the Blank,
Clear, and Cancel
keys. Press the Enter key
last. It does not show any action on the screen, but exiting the test
area successfully will verify its operation.
