409 = Positive Current Limit -Verify/Adjust for P001 - set default at 250% -Verify/Adjust for P003 - motor amps on data tag It's not in my T4 book either but it was in the TAC50 book.
I'm showing in my Magnetek manual 409 is a unexpected CPU reset. I would look at the boards and connectors first. I believe the error codes you are getting suggest you lost the communication from the CPU board.