I can't remember who was asking about changing the scale on Braun thermoscan, but I found the answer on page 9 in the manual. switch it on, press the button with the circle with a dot in it/memory and keep it pressed then press and release the activation button to switch over to the "change temp scale" mode. By pressing the activation button again the fahrenheit scale is activated and by pressing it again toggles it between f and C.

HTH's!