Chosen Solution
We have 6 iMacs in my office and of 2 wireless key boards suddenly the middle Roa all letters from A-L stops working. i tried connecting it to different macs also MacBooks non of them solved the problem. I also changed the battery. Is there anything i can do?
Sadly there is very little one can do with these keyboards once the keyboards membranes electrical matrix is damaged. I suspect you had a battery leak and the corrosive liquids damaged the keyboard. Time for a new one :-{
I did a teardown of this keyboard. It is just not very repairable: Apple Wireless Keyboard (A1255) Teardown
