Spent 11 hours on a ghost fault that was just a cold solder joint

Last Tuesday I got a 737NG with an intermittent RMP display glitch. Pulled the unit, bench checked it twice, swapped the antenna cable, even replaced the coax connector. Everything read fine on the ground but the pilot said it would drop signal around 20,000 feet every time. I was ready to blame the weather radar interfering or some weird grounding issue. Finally on the third day I decided to reflow every joint on the RMP board with a magnifier and a fine tip. Turns out there was a hairline crack on a pin where the ribbon cable plugs in. You could only see it when you flexed the board a certain way. Eleven hours of troubleshooting for a joint that took ten minutes to fix. Anyone else burn a full shift chasing a ghost that had a dumb mechanical cause like that? I'm starting to think my first move should be a wiggle test on every harness connection before I even break out the schematic. Has anyone tried one of those portable thermal cameras to spot cold joints quicker, or is that overkill for this kind of work?

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