have you checked back at the fuse board , to see if the fuse has (tripped ) if so push it back up, and try the shower switch again , see if the red light comes on, if not , the switch might be gone, you will need somebody to fit a new one,, or check the wireing in the switch to make sure it is tight, and this must only be done with (ALL THE POWER OFF ) in the home, be safe.....
b, March 2011