Sealed multiposition fiber optic connector

A multiposition optical connector 2 and a mating header 4 are disclosed. The connector includes a plurality of ferrules 10 for terminating individual plastic optical fiber cables 6. An alignment fixture 100 is used to precisely align each ferrule relative to the other ferrules and relative to peripheral mating surface protrusions 52 on a molded alignment plate 12. The ferrules are ultrasonically bonded to the alignment plate. True positioning for multiple fibers located in the multiposition connector relative to active optoelectronic devices 90 located in the header can be achieved when the connector and the header are mated. A previously assembled harness assembly using the optical connector 2 and a hybrid electrical and optical connector 202 is suited for use in making multiple connections to products, such as automobiles, in which the final assembly is completed in an assembly line.