That Tuesday I chased a ghost fault through three LRUs and found a chafed wire behind the aft galley panel
Spent 11 hours on a squawk that only showed up when the cabin was cold, swapped two ADIRUs and a display before I found the bare spot hiding behind a clamp. Made me miss the days when you could just follow the smell of burnt insulation, anyone else got a go-to trick for finding intermittent shorts before you start pulling boxes?
That "only shows up when the cabin was cold" detail is the whole clue right there, because cold shrinks metal and pulls that chafed spot tighter against the clamp until it finally makes contact. I do a wiggle test on every harness run before I touch a single box, grab the loom at each clamp point and flex it while someone watches the fault light. Nine times out of ten the short is sitting right where a zip tie or clamp was pulled too tight at the factory.