So many different issues on startup, I can't tell what's relevant for troubleshooting?

[acheong87]

So many different issues on startup, I can't tell what's relevant for troubleshooting.

Hey, everyone.

I'll try to be concise to boot.

History

• Samsung Galaxy S5 G900V, ordered online, new from Verizon, October 2015.
• I've never rooted a phone, nor attempted any "custom" procedures.
• Weeks or months ago, noticed an unlocked padlock icon on the loading screen, saying "Custom." Little concerned, but ignored it.
• 2 or 3 weeks ago, phone asked to do software update.
• Not enough space—started uninstalling apps as well as app updates for apps I don't use but can't get rid of. (In case uninstalling app updates can cause an issue like this.)
• Scrapped together just enough space, then proceeded with software update and reboot.
• Didn't notice any issues immediately (but then again, I don't typically reboot my phone for any reason—so maybe the issues started after my phone died by accident once).

Current Situation

• Phone unplugged; holding power button has no response (no vibration, no display).
• Remove battery, hold power button (to discharge, I've read), replace battery, hold power button: sometimes feel vibration. Still, no display, usually.
• Sometimes, I do get a display. Yesterday it was 1 in 2 times; now I'm on my 7th attempt with no display. I thought plugging the phone in helped, but I think that's in my head.
• Of the times I get a display, sometimes the phone hangs on the "Custom" padlock screen.
• Usually though, I get a "secure fail: kerrnel" in red font.
• Then I can hold power to feel the vibrate again, and often end up back at "secure fail: kernel." Or, used to. Now I'm luck if I see the display again.
• One time I was able to enter recovery mode and wipe the cache.
• Other two times I tried to enter recovery, I got a "secure fail: recovery" in red font.
• Before it started getting worse and worse over the past week, I used to be able to fully boot about 1 in 3 times.
• Also, while plugged in, unable to see the usual green charging animation. I did see it once about 10 attempts ago, and battery was at 88%.

Question

I have been all over the web, reading about ART vs. Dalvik, Odin, repair methods using another S5 (which my roommate does have), factory resets, etc. but I'm very confused about which scenario my device falls under. I feel like I'm seeing a larger variety of symptoms than most threads online, and what's odd is the gradual deterioration: Why and how would software do that? (I'm a C++ programmer, but I know nothing about phones and Android.) Can someone look at the symptoms and perhaps narrow things down a bit for me, like, "It can't be a Lollipop issue, because such and such."

Whoa, what? I've been typing this post for about 10 minutes without touching my phone, which was off and plugged in, and it just started up by itself and reached the "secure fail: kernel" screen. Is there a potential clue in the way it's starting itself? (Or, maybe it was "on" and stuck the whole time?)

 

[scipper77]

can you boot into recovery? power+home+volume up or down (cant remember which is for recovery options).

If you can you can try clearing cache (conservative and sometimes helps) or force a factory reset.

 

[acheong87]

Thanks, yes I was able to boot into recovery once (and it's volume up) and wipe the cache.

I was hoping to get just one normal boot before doing a factory reset and losing my data :-(

 

[SnowyRa1n]

Re: So many different issues on startup, I can't tell what's relevant for troubleshooting.

If you have Google sync enabled your app data and settings will be saved. If you are looking to back up photos and such and don't use Google Photos, plug it into your computer and save the necessary files (if possible).