If the wires in question are coming out of a factory harness I would check with the chassis manufacture odds are they use standard harnesses. Most manufactures use common color codes for a given circuit within a given year, a red wire with a black trace will be used for the same thing through out their fleet. Ford uses the same color code for a given circuit year after year.
If the wire are free running outside of any harness they may be Airstream and could be for options not included in your rig.
WBCCI 12156 AIR 3144 WACHUNG TAC NJ6
2004 Excursion 4x4
1991 34 ft. Excella +220,000 miles, new laminated flooring, new upholstery, new 3200 lbs axles