This page exists to document the weird errors you might see once or twice in a decade, but that can leave you scratching your head for hours.
Board works when flipped right-side-up, but stops working upside down!Edit
- Video: https://www.youtube.com/watch?v=9cs3f-oI-lI (MacBook logic board repair - 820-2530 no backlight repair)
- Cause: Weak solder joints are pulled out of contact by gravity when they are upside down.
- Fix: Reflow / replace solder joints.