There are only 2 boards in the unloader. A motherboard and an r2lc-06 radio board. What is the actual problem? "Doesn't work" does not help us to help you. If the radio board died, you could try an r2lc-08 board. The unloader came with a radio board that was an 06. Most of the time the 08 is a perfect replacement. If its an issue with the motherboard, you are probably out of luck. That board has programmable chips on it that only Lionel would have the code for.