Showerthought: A loose connector in a Cessna 172 taught me to trust my meter over the manual

I was troubleshooting a nav radio in a hangar in Boise, and the book said to check voltage at pin 4. My Fluke showed zero, but the pin looked fine. I finally wiggled the whole D-sub backshell and the reading jumped. Ever had a manual point you to the wrong spot entirely?

2 comments

2 Comments

taylor.jesse12d ago

Had that happen with a bad ground strap on a Cherokee. The manual said to test at the bus bar, but the real problem was a corroded connection under the insulation. My meter found the voltage drop the book never mentioned.

linda65812d ago

Check for voltage drop across every connection, not just the ends. Found a bad crimp under the heat shrink on my truck doing that.