a l'il back-story first...
about a week ago we were pulled over for not having brake lights, which is really weird because we have two sets of brake lights - the OEM and some tecniq led strips attached to the top.
the turn signals worked, the brake lights didn't.
got home and browse the ford wiring manual for the brake light fuse - #11 - and it's not blown.
test the + lead for the brake pedal switch and it has 13v; we decide to replace the switch anyway since it's 16 years old and we'll keep the original as a spare.
remove the IPCW led tailights and notice some interesting electrical issues
the fuzziness on the plastic is havelock wool which is installed throughout the van for insulation and to reduce drafts - our van had a noticeable draft at the tailights.
turns out that the circuits on the back of the lights need airflow to stay "cool" and the wool was insulating the circuits.
we replaced the IPCW lights with junkyard lights and still no brake lights.
search the forum and the interweb for "no brake lights" and the multifunction switch might be bad, so we order one of those but it'll take a week to get here.
as a last resort, we break out ford volume 1, find the electrical troubleshooting section and see if there's something else that might cause the brake lights to not work.
first = is fuse 11 good? yes
second = is fuse 39 good? no
turns out that the fuse 11 circuit runs thru the fuse 39 circuit (multipurpose switch).
now we're waiting on new ford taillights to finish this "project."
as an aside, anyone with stock taillights that wants some really bright 3156 / 3157 LED's, check out
Alla Lighting on amazon
these seem as bright or brighter than the IPCW taillights and they're interchangeable, so if a brake light goes out, we can swap with the reverse light in a pinch.
we're also replacing all fuses with
easyid to make finding a dead fuse easier.