Yours may not have had the cigar lighter option then.
Normally a vehicle gets the same harness, including most of the wires for optional accessories. But for all we know Broncos got the harness that best fit the build. Meaning no radio or cigar lighter wires at all.
Most of our (at least later model) EB's came with stuff like dome light wires, under-dash map light wires, radio wires and such, but maybe the '66 through '68's did not always?
Can't tell you from my '68 because it's got all new aftermarket wiring harness in it. So no help there.
And of course, the Chilton's wiring diagrams for the '66 to '70 models don't even show a cigar lighter!
However, starting in '72 we see the single Blue w/white wire that feeds the lighter. But at the fuse panel you're looking for a Green w/yellow wire instead.
First the power comes from the fuse panel via the Green w/yellow wire over to the headlight switch, where it is spliced to the Blue w/white wire and then down to the lighter.
It appears that the lighter is not actually powered through the headlight switch, as much as it simply shares a feed from the fuse panel to the dome light/map light circuit.
If yours is the same, then look for a Green w/yellow from the fuse box, then check it out up at the headlight switch.
In lieu of those, just run your wire from the ignition switch. The disadvantage of this is that you need the key in ON or ACC for the lighter to work. Not a deal-breaker perhaps, but not as convenient as it being powered all the time.
Paul
blue white green yellow
But for your original wire,
