Control panel, test

This function is used to check the control panel buttons.
Note:
Due to various equipments of the control panel, some buttons are termed with large letters instead of what they are labeled with. See picture below.
Test conditions:
Procedure:
  1. Start the function.
  2. Push a button for at least 1 second and check that the status of the button is correct.
  3. Press "OK" to finish.
  4. The function is done.
If the function fails, check the test conditions and try again.