I'ts a Printing problem

Clean the carriage shaft and carriage lock at rear side of carriage unit , can lubricate the oil pad in carriage after cleaning
check for the port setting for ECP in biose setup
and check the connective cable and the white color print head cable connected to print head and logic pca ,remove the print head and if the pins are not aligned properly its need to be replaced

One possibility- I think this printer uses a mechanical switch for the head carriage home position sense. This is located on the left side of the machine, down underneath where the printhead carriage assembly rides. This switch can become erratic, and cause an error condition at random.

I think the switch is housed in a small plastic enclosure. Repair involves either replacement of the switch, or, removal of the enclosure and cleaning with a contact cleaner of some sort.