blue wire n.
[IBM] Patch wires (esp. 30 AWG gauge) added to circuit boards
at the factory to correct design or fabrication problems. Blue
wire is not necessarily blue, the term describes function rather
than color. These may be necessary if there hasn't been time to
design and qualify another board version. In Great Britain this
can be `bodge wire', after mainstreanm slang `bodge' for a clumsy
improvisation or sloppy job of work. Compare purple wire, red wire, yellow wire, pink wire.