Samsung Galaxy S5 weird hard brick

[TheLukeMartinez]

Ok, so I have had my SM-G900T1 for about a year now. Never rooted, exposed to water, or anything; it's been in a LifeProof case since day 1. About a week ago, I was browsing Facebook when the phone froze. I removed the battery to reboot to find the phone would no longer boot, recognize that it is charging, or show up on a computer. Could not boot to download mode, etc. I let the phone sit overnight without the battery and attempted to boot. It flashed the Samsung logo roughly 3 times at about a second each and then nothing. Getting desperate to avoid a repair center, I ordered a download mode jig from eBay. To my surprise, the phone booted into download mode and stayed on until I removed the battery (roughly 5 minutes later) to insert a SD card with what i believed was a debrick image. After I inserted said SD card and attempted to boot using the jig, I was back to square one with a dead paperweight. I then let the phone sit overnight without a battery and tried again the following morning. Upon inserting the battery and the download mode jig, the phone turns on and boots to download mode. I then left it on the charger (while powered in download mode) throughout the day while I was at work. To my surprise when i got home about 9 hours later, the phone was STILL on and in download mode. Cool. I plug into my PC in an attempt to use Odin and I get the USB device has malfunctioned message. Doesn't show up in Odin or Kies. Finally I try to restart download mode (maybe it will work now after the phone has been running all day) and I am directly back where I started with a S5 paperweight. Any suggestions? I've spent countless hours scouring forums to no avail. I am very close to bashing my face in with this expensive brick in my lap, haha.

 

[Rukbat]

It could be (since I can't actually debug the phone - no one can - so it's a guess) bad ROM where the system sits or bad RAM where the system needs to use it. When something that major like that goes, you replace the motherboard. Considering how new the phone is, it may be worth it. (Remember, with a few million S5s sold, one phone with bad storage or memory is a tiny percentage. It's not so great when you're the one it hits, but if that's the only motherboard it happened to it's not bad odds,)