Uncommon Issues

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!

 * 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.