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Spent 9 hours troubleshooting a bad ground on a G1000 in a Cessna 172 last Thursday
Guy brought his plane in for an intermittent PFD flicker. Worked fine on the bench but kept losing data in flight. Checked connectors, swapped LRUs, even re-pinned the backshell. Turned out to be a corroded ground lug behind the instrument panel that looked clean but measured 12 ohms. Never again will I skip the continuity checks first. Anyone else waste a whole shift on something that simple?
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margaret_gonzalez2517d ago
Did you at least get to bill him for the full 9 hours of "diagnostic troubleshooting"? Asking for a friend who's definitely not still bitter about a three-day dead short in a piper warrior.
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grayc2717d ago
Piper Warrior is a single wire ground return system. That dead short was probably in the master relay or the alternator field circuit, not the wiring itself. Been there with the same model.
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martin.felix17d ago
That 2008 Warrior I worked on had the same short and it took me 8 hours on the clock before I found it in the push-pull alternator switch wiring itself. @grayc27 is right about the master relay being a common spot, but in my case the wire had chafed behind the switch panel on a loose screw. Told the owner it was a thorough inspection of the whole system, not just chasing a single wire. Billed the full 9 hours and he didn't blink because he saw me pulling every panel.
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