Which statement correctly identifies how to identify a wire in a bundle?

• A. The identification code marked on the wire
• B. The color of insulation alone
• C. The gauge marking on the jacket
• D. The wire's length within the bundle

Answer: (A)

In aircraft wiring, the reliable way to identify a wire inside a bundle is the identification code printed or etched on the wire’s insulation. That code is chosen specifically to be unique to that conductor and to be cross-referenced with the aircraft’s wiring diagrams, circuit listings, and maintenance records. Because of that, you can precisely determine the circuit function, source, and termination points just by checking the code.

Relying on color alone isn’t dependable because many wires share the same insulation color, and colors can fade, be damaged, or be reapplied during maintenance. Markings on the jacket showing gauge aren’t standardized across all wires and can be missing or misleading in practice. The physical length of a wire inside a bundle also isn’t a stable identifier since wires can be trimmed or rearranged during servicing. The printed identification code stays with the wire and provides a consistent, traceable reference.