The ACM (radio/amp part) needs recoding. Forscan will do it, but you need an OBDII device with the high-speed and medium-speed switch - specific for Fords. I got one from ebay quite cheaply. Forscan needs a license too, but you can get a two month free trial pretty easily.
Initially, I just disassembled the
ICC I had bought and swapped the LCD over - no problems with my own radio and the new screen. Then I put the
ICC with my old screen and the new ACM in.. "Radio Code Error" showed up and I used Forscan to "recalibrate" it. Fixed.
Every time you reconnect power to the unit you will get the error while on accessories. You need to turn the key to ignition and the code error goes away once Forscan has programmed it correctly. It remains properly paired until it's unplugged from the battery again.
I'm skeptical it's not fixable. For starters, you've connected up a 9v battery and got the screen to light up. That's not the screen which is broken, it's the circuit powering it which is what we are trying to repair here.