Took me 3 shifts to find a chafed wire in an engine harness

I had this King Air come in with an intermittent mag drop. Compressor checks were fine, swapped plugs, still there. Turned out to be a wire rubbed through inside the harness behind the firewall. Probably 2 hours of actual troubleshooting stretched across 3 days because I kept second guessing myself. Did a continuity test 4 times before I finally pulled the harness open and saw the copper. Anyone else ever chase a gremlin like that and feel dumb after?

3 comments

3 Comments

terry_jones21d ago

Try wiggling the harness while watching the meter. Found mine that way.

allen.charlie20d ago

Nothing beats a multimeter for chasing down a ghost connection like that. Harness wiggling is a classic, just make sure you don't accidentally short something out while you're at it. Always tape back any exposed wire you mess with.

charlie_ellis21d ago

@terry_jones wiggling works but sometimes you just need to stop and cut the tape.