That old wiring diagram book I found saved my butt on a King Air job

I was fixing a comm issue on a King Air 200 last Tuesday and the factory wiring diagram just didn't match what I was seeing in the panel. Pulled my hair out for like 3 hours tracing wires that went nowhere. My mentor Tom who retired 10 years ago gave me this beat up 1987 wiring book before he left and I almost threw it away. I cracked it open out of desperation and it had the exact correction for a modification the factory never updated. The old timers really did know their stuff about keeping paper copies of everything. Has anyone else run into factory diagrams that were flat out wrong for older airframes?

2 comments

2 Comments

ray_hernandez2d ago

Factory diagrams that were flat out wrong" - I'd say they weren't wrong, you just had the wrong revision. The real issue is people don't check the drawing number against the aircraft's logbook mods before they start. Three hours of tracing wires sounds like a lesson in reading the revision block first.

kimr102d ago

Yeah totally agree. I had one where I spent like an hour chasing a ground fault that turned out to be a whole different wiring harness from a field mod nobody wrote down. Revision block is the first thing I check now too.