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How do you diagnose a board that has intermittent power problems?
Boots normally then dies randomly at different times, then does not boot at all for some time then randomly starts working again. Wondering what the first steps are in diagnosing something like this.
"what the first steps are in diagnosing"
What about history fault???
How much time stays on?
Do you have original Magsafe 2 (two) charger?
Disconnect internal SSD and try your USB test OSX on both USB ports.
Also disconnect LIO flex and test the board alone.
No matters fan is loud and battery not charging, just for test.
Try the machine in SMC bypass too.