Macbook Pro/Air - no power

[ScutBoy]

I've got a couple/three Macbook Pros and Macbook Airs from a local charter school that "don't work", and I offered to give it a shot to see if I can repair.

The common symptom is that none of them will show any signs of powering up, even after SMC reset, disconnecting/reconnecting the battery, removing/replacing the SSD. etc. They do seem to charge their batteries, and SMC reset does show the power light changing as I would expect, but otherwise no dice.

No obvious liquid damage or evidence of drops.

Machines are anywhere from 2013 to 2015.

Any thoughts appreciated!

 

[3lectr1c]

Check out Louis Rossmann's stuff on YouTube. He's probably repaired dozens of them with the same problem yours has.

 

[ScutBoy]

With more examination, it seems that when the power is plugged in - or there's charge in the battery - the CPU heats up enough to start the fan, even though the machine is otherwise dead. I will probably pull the logic board to see if I can find any obvious failed components, etc.