Chosen Solution
My computer is stuck in a boot loop. As soon as the battery is plugged in the fan turns on, computer chimes, fans stops, fan on, chime, and so on. The screen remains black throughout. I have replaced the logic board, RAM, and battery all without any improvement. Resetting the SMC and PRAM did not make any difference. If I unplug the ribbon cable from the keyboard, plugging the battery in does not start the fan or the chime, however with the cable unplugged I can’t turn on the computer at all. What do I do next?
Since you have the same problem after replacing logic board, which is the Mac heart and brain, it sounds like one of the modular components might be the issue. Disconnect all and everything from the logic board, battery included and plug in the magsafe and you should see the board starting up, unless you have a faulty magsafe or logic board. If that happens, reconnect components to the board one by one, always disconnect magsafe first. That should be enough to pinpoint what’s preventing normal functioning.
