Weird Mac Issue

[rickyamin]

I am having the weirdest issue on my MacBook Pro. It randomly shutdown while using it. However, it never does so when I have it plugged into an external monitor. There are no shutdown reports or Kernel panics.

So far I have reset the SMC and PRAM but no to avail. I also took the Mac into the Genius Bar and they cleaned out the clogged fan, ran various graphics test and overnight exhaustive test for 48 hours but found nothing. I am still having the issue and am forced to now use my macbook pro only with an external monitor to avoid random shutdowns.

 

[hobowankenobi]

How old is it? How is the battery?

On a couple of occasions I have seen MBPs behave oddly and have power envents if the battery was failing. Have you noticed it happening only on battery, or also plugged into power?

 

[rickyamin]

Great Point ! I forgot to mention, the battery passed with flying colors too. I have it when its plugged into the power too.

Health Information:

Cycle Count: 719
Condition: Normal
Battery Installed: Yes
Amperage (mA): -139
Voltage (mV): 12592

 

[NoBoMac]

What vintage Mac?

When not connected to the monitor, is the laptop in your lap or moving around? MAYBE, cracked motherboard or something not quite soldered/connected correctly (and depending on vintage, RAM not seated properly and or disk replacement went bad [eg. Cable damaged]). While, assuming, stationary attached to the monitor, not flexing, getting jostled, connections are fine. Seen this with other computers over the years.

Example, olden days, work had a mini-fridge sized engineering system. Would suddenly crash and reboot.We finally found a pattern: one guy liked to lean on the machine, causing it to move a little, wiggle. Yup, service guy found the board was cracked (back in the day boards were the size of pizza boxes and not as dense as today).

 

[ranger_rick]

Is the battery original? its possible that if the battery was replaced that you have a dud. Use coconut battery analyzer.

My Macbook Pro would only boot if i reset the SMC/PRAM and then plugged in the magsafe. After that I could unplug it and it would run off battery power. I replaced the battery twice with no change. Long story short, it turns out it was keyboard issue! ugh

Is it possible you have bad video card since the issue doesn't happen when using an external monitor? Short in the video or display circuit??

 

[rickyamin]

All original and MacBook Pro (Retina, 15-inch, Mid 2014). I bought it from the Apple store back in 2015. Genius bar did all the exhaustive graphic checks and no issues.

 

[BrianBaughn]

If you were to create a new user account and try "using it" the way you normally do without the external monitor connected you could perhaps eliminate user account corruption.

 

[hobowankenobi]

Any other clues...

Happens only when plugged into power, or only when not plugged into power? Only when moving it around?

You could try booting to Safe Mode, to rule out any third party software issues, though that seems unlikely.

One thing Apple used to do religiously: Reinstall the OS to rule out software issues. If you have the storage available, you could clone the drive, and do a clean install and test again to see if you replicate the issue. If it does it again after clean install....likely not a software issue.

Back to hardware then....likely culprits would be battery, power brick, DC-in converter board, logic board. LB covers alot....as nearly everything else is soldered on: RAM, CPU, GPU, etc.