I have a cm848 in an 03 Cummins that seems to have gone brain dead, can read a serial number out with one scan tool but its stuck in rom boot and wont flash. Gets to about 58% on flash and then says Write transfer request- failed to start. I have another ecm to swap it but while Im here I have nothing to loose trying things. On a read, it doesnt detect a vin and wont generate a stock file either. I tried a smarty recovery file but get an error after 60%. Any more ideas ?