I just changed the battery in my Casio W-756 (Module 3100 innards), and now some buttons do different functions. It has 5 buttons: two on each side and one button center bottom. Normally the top right button is "Light" and the bottom right is "-" (the bottom center button is "+"). But now the top right button seems to do nothing and the bottom right button is the "Light". The other 3 buttons perform the correct functions. I reset the watch and removed/reinstalled the battery but it still has those 2 buttons doing the wrong function. Physically all buttons seem fine on the module / circuit board.
Does the Module 3100 have different "personalities"? How do I toggle between them to get back to the functionality it had? Thanks!