Electrical Circuit Numbering and Color Codes

Cables and wire used in electrical wires have colored insulation on them. Cables and wires are covered with different color insulation. Even two colors are used on one wire to make more color selection. The color on wire insulation have its specific purpose. The wire color coding represents different wires and different circuits. Sometimes numbers and symbols are included in schematic diagrams. These codes and numbers help technicians and engineers working on the specific systems.

Wiring colors are standard for all manufacturers. They use different color schemes according to their own need. But they specify their color scheme in service manuals and other service material. This is a good idea to learn the manufacturer wiring color standard and coding before working on a specific system.

In electrical wiring the first color group letters shows the base color of wire and the second letters are showing the color of the strip or tracer on the wire. We can say for example we have a wire for which the diagram shows the letters BLK/RED. This shows black base color for wire with a red color strip on it or red color tracer on it. Tracer is a line or a dashed line on the wire whose color is setup different than the base color of the cable insulation. This is made to make more selection in case of complex wiring in a system.

Cars manufacturer Ford use four coding methods for color coding their wires in their cars:

a.       Solid or one color

b.      Base insulation color with a stripe or tracer on            the base color

c.       Base insulation color with dash line or hash              marks

d.      Base insulation color with dots on the base color

The other car manufacturer Chrysler adapted the numbering scheme to show the circuits on the wiring diagram. This numbering scheme includes circuit identification, wire gauge and color of wire. All these information are included in the number used by Chrysler.

Generl Motor uses even more detailed and complex coding number scheme in their cars. Their identification code includes wire color, wire gauge in millimeters matric, the circuit number and the ground identification.