Method of making a wire harness

A method of making a wire harness, comprising the steps of:

• providing a main circuit part including an insulated conductor wiring circuit plate in which conductors are arranged on a base insulation film to form a wiring circuit, wherein the step of providing the main circuit part further includes forming the wiring circuit of said insulated conductor wiring circuit plate by turning, bending, crossing or branching said conductors;
• covering said base insulation film and said conductors of the insulated conductor wiring circuit plate with a flexible insulation material;
• removing the flexible insulation material along only a terminal edge of said insulated conductor wiring circuit plate while said base insulation film remains, so that ends of said conductors are exposed above said base insulation film located thereunder to form a connection area having a predetermined width, said connection area being devoid of said flexible insulation material thereby leaving a belt-shaped space across the terminal edge of said insulated conductor wiring circuit plate;
• providing a branched connection part including a printed wiring plate having conductive paths;
• forming a connection area along an edge portion of said printed wiring plate by disposing ends of the conductive paths in a side-by-side relationship;
• overlapping said connection area of said printed wiring plate on said connection area of said insulated conductor wiring circuit plate so as to directly contact and electrically connect said ends of said conductors with the ends of the conductive paths, respectively;
• forming a plurality of mounting holes disposed at predetermined positions in said printed wiring plate;
• and
• providing a plurality of leading electrical wires connected to at least one connector, said connector having connector pins which are inserted into said mounting holes of said branched connection part so as to connect said leading electrical wires to the conducting paths formed on the printed wiring plate.