Wiring diagrams Introduction – sheet 6
Introduction – sheet 6
Wiring diagram 3-6 · 2007 Focus
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Introduction E6Yenz01 3-6 2007 Focus 6/2006 Circuit Numbering and Wire Identification Circuit Numbering: Ford has introduced a world-wide uniform system for circuit numbering and wire identification. The system is called Function, System-Connection, or FSC for short. FSC was developed mainly to assist in vehicle development and production processes, but is also helpful in troubleshooting electrical circuits. Example: BK/RD 31S-AC3A Function System-ConnectionColor Function: The first two digits identify the function of the wire. In this case, the function code includes the letter “S” to indicate it is an additionally switched function. The function part of the circuit number is the most helpful to the technician in troubleshooting a circuit. A complete list of function codes and their descriptions is included on the next page. System-Connection (including branch): Systems are related to subsets of the vehicle circuitry. A complete list of the system codes can be found on page 3-8. Immediately following the system letter code is the connection number specific to that system. A branch identification is used to differentiate wires in one connection with the same function. Wire Identification (wire colors): The wire identification consists of a basic color and an identification color, and is determined directly from the wire’s circuit number. In the schematics, the wire colors are indicated next to the wires. The basic and identification colors are abbreviated using the international norm IEC 757. The abbreviations are listed in cell 4, “Symbols”. Each function code has a specific basic color associated with it, which can also be seen in the chart of function codes on the next page. The identification color is a colored stripe used to differentiate several wires with the same function within one component connector. Using the circuit number and wire identification used in the above example we know the following information about the wire: BK/RD 31S-AC3A Function:31 = Ground S = Additionally switched circuit System:AC = Headlamp leveling Connection:3 = Switch connection A = Branch Color:BK = Basic color black (determined by function 31) RD = Identification color red (red stripe)
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