A very unique problem: My MacBook Pro randomly shuts down and won’t boot?

[asdfguy]

I have a 2015 15” MacBook Pro, and it randomly shuts down and won’t boot back up. I don’t know what’s causing this behaviour.

I was just browsing the web, and it shut down and won’t power on again. I plugged in the MagSafe and the light is amber and changes to green after 20min or so. That means MacBook is charging the MacBook. However, the MacBook still won’t power on.

I opened it up, and unplugged the battery and pressed the power button to drain any electricity in the motherboard. I plugged the battery cable, and it booted up fine. The MacBook worked for a couple of days, but it randomly shut down again and wouldn’t boot up. I repeated the steps again, and it worked for a few days and does it again.

This happens regardless if it’s on battery or plugged in.

A couple of days ago, while I using the MacBook while running on battery, it went to sleep and wouldn’t wake up. It said battery low, and I need to plug it in. But when I plugged the MagSafe, it booted into MacOS but it says the battery is fully charged. I checked the battery cycle, and it’s 300. I have tried NVRM/PRAM reset and SMC reset with no luck.

The MacBook randomly shuts down when I’m running MacOS, Bootcamp, or Apple’s built-in diagnostics.

I took it to Apple Store, and they ran their in-depth diagnostics, but it showed there were no faults with the MacBook. They opened it up and say no problems inside as well.

What could be causing this?

 

[dirtybeatfreak]

How long did the tests take that they did? I ask because they are notorious for running basic MRI diagnostics and calling it a day, these tests are more of a roll call and quick health check. Did you leave it with them for a couple of hours or they do it there and then? That said, in their defence, the full diagnostics they run (there are 2 versions) aren't infallible so it may be that there is hardware fault but it wasn't detected.

If the issue is happening even with the battery unplugged then it's possible that there is something up with the Logicboard, but without seeing the unit for myself, that is pure speculation ofc. 300 charge cycles for a battery is very low. Anything 1k+ for MBP is considered high.

In short, don't rule out hardware issues.

 

[Hades]

Is it actually shutting down or is the screen just going off? E.g. there is a known issue with some macbooks (can't remember which year) where the screen cable is too short. So over time it breaks as the lid is opened and closed. Could it be that?