An automotive wiring harness employs wires and cables. Each is made up of at least seven conductor strands (A), and
covered with an insulating material (B).
Within Volkswagen, wire and cable are classified in three general categories, and then specified according to size, type of insulation, and color.
Wires are stranded conductors ranging in size from 0.35 mm2 to 6.0 mm2 (approximately 22 to 9 gage (AWG)) that
make up most of a vehicle’s wiring harness. Smaller sizes save cost and weight. The larger sizes accommodate higher current loads with less resistance.
Wire larger than 6 mm2 (0 gage (AWG) is generally considered “cable.”
Wire size (cross-sectional area) is the primary factor that will determine the current-carrying capacity of a conductor. Standard sizes differ slightly, depending on which measuring standard is used.
Volkswagen uses wire and cable that is manufactured according to the German industrial or “DIN” standards. Wire size is defined by cross-sectional area, and is measured in circular mils (mm2). As in the example shown, “0.75 mm” refers to the area (0.75 mm2), not the diameter.
Sizes of wire and cable originating in North America are described according to the American Wire Gage (AWG) standard. The standard wire sizes in both systems are roughly equivalent.