deisel with circuit code U1900, what does this mean?

Question

vehicle after running awhile, when you shut it off, it will not start back. Hooked up to scanner and scanner read code U1900.

Answer 1

U1900 CAN communication bus fault- error recieved

This is not the reason for no start,This is for the ABS (antilock brake) module, the instrument panel,and the trailer brake control,What you want is a "P" code,