Wiring color codes are used by manufacturers to assist the mechanics in identifying the wires used in many circuits and making repairs in a minimum of time. No color code is common to all manufacturers. For this reason, the manufacturer's service manual is a must for speedy troubleshooting and repairs. Wiring found on tactical equipment (M-series) has no color. All the wires used on these vehicles are black. Small metal tags (fig. 2-87), stamped with numbers orFigure 2-87. - Metal tag wire identification. codes, are used to identify the wiring illustrated by diagrams in the technical manuals. These tags are securely fastened near the end of individual wires. Wiring diagrams (fig. 2-88) are drawings that show the relationship of the electrical components and wires in a circuit. They seldom show the routing of the wires within the electrical system of the vehicle. Often you will find ELECTRICAL SYMBOLS used in wiring diagrams to simulate individual components. Figure 2-89 shows some of the symbols you may encounter when tracing individual circuits in a wiring diagram. Wire terminals are divided into two major classes - the solder type and the solderless type, which is also known as the pressure or crimp type. The solderFigure 2-88. - Wiring diagram of a passenger vehicle showing standard equipment and color code for wires. Continue Reading