Had this a coupla times now, its the connector that comes up the front of the dev unit. If you don't route the cable straight up through the gap with the black mylar cover, the cable gets pinched or cut when you put the toner feed system back on. Will cause a 7101-7104 code depending on the dev unit.
=========================== Think of how stupid the average person is, and realize half of them are stupider than that. - G. Carlin