When I bought my first A4000T the mouse didn't work. There was a burned trace on the ports board that I repaired with 30 gauge wire wrap wire. It was easy to see and find with an ohm meter. I bet I know how it happened now:-) The machine did at least boot like that however it still takes forever and a day to start unless I use 40.68 ROMs from a desktop machine.
Good Luck getting your "T" working again.
-Jeff