Question about locating intermittent shorts on Piper archers

Spent 3 hours last week chasing a intermittent short in the right nav light circuit on a 1978 Piper Archer. I finally found it by isolating the circuit and using a tone generator on each wire segment instead of the usual continuity test. Has anyone else had better luck with this method on older wiring harnesses?

2 comments

2 Comments

morgan.cameron4d ago

Did you try just wiggling the hell out of the wingtip while watching the ammeter? I had a similar issue on a Warrior and found the short was actually inside the nav light fixture itself (the little spring contact had corroded and was occasionally grounding out). It drove me nuts because I kept looking at the wiring harness when the problem was right there in the lens assembly. Sometimes the tone generator trick works great, but on the older Piper harnesses with that brittle red and white insulation, I've found the actual break or chafe can hide inside a connector or a splice that looks fine from the outside.

joseph_lewis924d ago

Hang on, did you have to pull the entire wing off to get to the harness, or were you able to access the wires through the inspection plates? I mean, on those old Pipers the wiring can be wrapped up pretty tight in the wing root. Idk, maybe it's just me but I always end up breaking more stuff trying to get to the wires than I do actually fixing the short. Did the tone generator pick up the short even with the engine running or did you have to shut everything down first?