I've been running the latest CM10 M release for a couple weeks now. Today I upgraded to the latest modems. Everything was working great for a few hours when my phone randomly shut off and now won't turn back on.
I've tried pulling the battery and charging. Can't ever see anything on the screen although it does vibrate sometimes when I hold the power button. LED will turn on when charging.
Any ideas or suggestions?
See if you're able to boot straight into download or recovery, thus will show intact boot and recovery systems.
One other test, pull battery and with phone off plug into your PC if it shows a red light its likely hard bricked.
I had the unfortunate experience of flashing wrong kernel and bricked my phone was not going to recovery or download. However if you can get to these then it may be a soft brick and restore with odin
Sent from my VS920 4G using Tapatalk 2
One my phone got stuck
jerhurwitz said:
I've been running the latest CM10 M release for a couple weeks now. Today I upgraded to the latest modems. Everything was working great for a few hours when my phone randomly shut off and now won't turn back on.
I've tried pulling the battery and charging. Can't ever see anything on the screen although it does vibrate sometimes when I hold the power button. LED will turn on when charging.
Any ideas or suggestions?
Click to expand...
Click to collapse
Once my phone got stuck because I flashed a new recovery that wasn't compatible with my phone so each time I tried to boot into recovery or tried to turn on the phone nothing would happen. The only thing that got my phone working again was to go into download mode (Odin) by holding power, volume down and home buttona and than canceling it. from there the Rom started working again. I don't know if it will help in your case but you can always try.
That was a strange experience. Left it plugged in for a few hours. Came back, and was able to boot normally... although the battery was extremely low despite being plugged in for a few hours. No problems since then.
Congrats =)
Seems like disaster was avoided.
jerhurwitz said:
That was a strange experience. Left it plugged in for a few hours. Came back, and was able to boot normally... although the battery was extremely low despite being plugged in for a few hours. No problems since then.
Click to expand...
Click to collapse
Do you know what percent your phone turned off at? Around what percent? Was it 23-25%?
HTC One M8, S-Off, Skyfall latest on 4.4.4, stock kernel, TWRP 2.8.1.0. Have been running Skyfall latest since a few days after its release, and TWRP 2.8.1.0 similarly. No problems to report so far.
I was using my phone today as one would, browsing Facebook through the app, and my phone freezes. Screen goes black, power off. Phone was probably at 80-85% battery when this happened.
I am no stranger to freezes and hard reboots, so I expected the phone to come back up shortly after this. It did not.
Tried to reboot via ADB. Couldn't detect the device.
Tried to reboot into recovery by holding Vol Down and Power. No response.
Tried to reboot into a soft reset by holding Vol Up and Power. No response.
Tried to force a battery recalibration by plugging in the phone to a charger* and holding Vol Up, Vol Down, and Power for two minutes. No response. (*the charger was not the stock HTC charger, as I don't presently have access to that, but was rather a generic charger rated for [email protected])
Somehow, miraculously, after leaving the phone plugged in for a few minutes more and fumbling a bit with (I think) the Power and Vol Up, the phone powered on, rebooted twice, and then entered the OS normally. Was stable for what seemed like about 5 minutes. After receiving a few text messages and in the middle of responding to one, it froze and powered off as before.
Last system-level tweaking that I did was to accept the latest SuperSU upgrade a few days ago. That needed to reboot into recovery, install a zip, and reboot again. All appeared to work correctly, and phone booted back up afterwards without issue. Appeared to be stable until today. I'm not blaming the SuperSU update just yet, and it seems an unlikely culprit given that the phone booted back up without issue and was stable for several days following.
Thoughts? Would greatly appreciate any troubleshooting ideas beyond these.
Update 1: After leaving it plugged in for a few minutes, I tried the battery calibration approach again. The device powered on and showed the initial boot splash (the one with the development notice in ugly red). I then released all buttons, and after a few seconds the screen went black. Would not respond afterwards. Beginning to suspect this may be a power issue.
devmage said:
HTC One M8, S-Off, Skyfall latest on 4.4.4, stock kernel, TWRP 2.8.1.0. Have been running Skyfall latest since a few days after its release, and TWRP 2.8.1.0 similarly. No problems to report so far.
I was using my phone today as one would, browsing Facebook through the app, and my phone freezes. Screen goes black, power off. Phone was probably at 80-85% battery when this happened.
I am no stranger to freezes and hard reboots, so I expected the phone to come back up shortly after this. It did not.
Tried to reboot via ADB. Couldn't detect the device.
Tried to reboot into recovery by holding Vol Down and Power. No response.
Tried to reboot into a soft reset by holding Vol Up and Power. No response.
Tried to force a battery recalibration by plugging in the phone to a charger* and holding Vol Up, Vol Down, and Power for two minutes. No response. (*the charger was not the stock HTC charger, as I don't presently have access to that, but was rather a generic charger rated for [email protected])
Somehow, miraculously, after leaving the phone plugged in for a few minutes more and fumbling a bit with (I think) the Power and Vol Up, the phone powered on, rebooted twice, and then entered the OS normally. Was stable for what seemed like about 5 minutes. After receiving a few text messages and in the middle of responding to one, it froze and powered off as before.
Last system-level tweaking that I did was to accept the latest SuperSU upgrade a few days ago. That needed to reboot into recovery, install a zip, and reboot again. All appeared to work correctly, and phone booted back up afterwards without issue. Appeared to be stable until today. I'm not blaming the SuperSU update just yet, and it seems an unlikely culprit given that the phone booted back up without issue and was stable for several days following.
Thoughts? Would greatly appreciate any troubleshooting ideas beyond these.
Update 1: After leaving it plugged in for a few minutes, I tried the battery calibration approach again. The device powered on and showed the initial boot splash (the one with the development notice in ugly red). I then released all buttons, and after a few seconds the screen went black. Would not respond afterwards. Beginning to suspect this may be a power issue.
Click to expand...
Click to collapse
Well the good news is that you aren't bricked, if the phone gives any signs of life then you are not bricked. Have you always installed SuperSu updates through recovery? I always select I believe it says "normal" and let it do it's thing and until now (knock on wood) haven't had any issues updating binaries that way. I would go back to stock and see if your problems continue or flash the previous SuperSu and see if it still happens.
devmage said:
HTC One M8, S-Off, Skyfall latest on 4.4.4, stock kernel, TWRP 2.8.1.0. Have been running Skyfall latest since a few days after its release, and TWRP 2.8.1.0 similarly. No problems to report so far.
I was using my phone today as one would, browsing Facebook through the app, and my phone freezes. Screen goes black, power off. Phone was probably at 80-85% battery when this happened.
I am no stranger to freezes and hard reboots, so I expected the phone to come back up shortly after this. It did not.
Tried to reboot via ADB. Couldn't detect the device.
Tried to reboot into recovery by holding Vol Down and Power. No response.
Tried to reboot into a soft reset by holding Vol Up and Power. No response.
Tried to force a battery recalibration by plugging in the phone to a charger* and holding Vol Up, Vol Down, and Power for two minutes. No response. (*the charger was not the stock HTC charger, as I don't presently have access to that, but was rather a generic charger rated for [email protected])
Somehow, miraculously, after leaving the phone plugged in for a few minutes more and fumbling a bit with (I think) the Power and Vol Up, the phone powered on, rebooted twice, and then entered the OS normally. Was stable for what seemed like about 5 minutes. After receiving a few text messages and in the middle of responding to one, it froze and powered off as before.
Last system-level tweaking that I did was to accept the latest SuperSU upgrade a few days ago. That needed to reboot into recovery, install a zip, and reboot again. All appeared to work correctly, and phone booted back up afterwards without issue. Appeared to be stable until today. I'm not blaming the SuperSU update just yet, and it seems an unlikely culprit given that the phone booted back up without issue and was stable for several days following.
Thoughts? Would greatly appreciate any troubleshooting ideas beyond these.
Update 1: After leaving it plugged in for a few minutes, I tried the battery calibration approach again. The device powered on and showed the initial boot splash (the one with the development notice in ugly red). I then released all buttons, and after a few seconds the screen went black. Would not respond afterwards. Beginning to suspect this may be a power issue.
Click to expand...
Click to collapse
Make sure you aren't trying to power it on while still plugged in. The charging animation bug really rears its ugly head sometimes when trying to do that.
The Stig 04 said:
Well the good news is that you aren't bricked, if the phone gives any signs of life then you are not bricked. Have you always installed SuperSu updates through recovery? I always select I believe it says "normal" and let it do it's thing and until now (knock on wood) haven't had any issues updating binaries that way. I would go back to stock and see if your problems continue or flash the previous SuperSu and see if it still happens.
Click to expand...
Click to collapse
I would love to go back to stock if I could get the device to turn on.
This was the first SuperSU update that I can remember having installed, so yes, I've always installed through recovery. The update even prompted me that, for HTC devices, better luck is had via updates through recovery.
dottat said:
Make sure you aren't trying to power it on while still plugged in. The charging animation bug really rears its ugly head sometimes when trying to do that.
Click to expand...
Click to collapse
I'm unaware of this bug. When disconnected, the device still refuses to reboot via any of the usual reboot patterns (Power, Power + Vol Up, Power + Vol Down, Power + both Vols).
devmage said:
I'm unaware of this bug. When disconnected, the device still refuses to reboot via any of the usual reboot patterns (Power, Power + Vol Up, Power + Vol Down, Power + both Vols).
Click to expand...
Click to collapse
OK. So couple more questions....
Does the power light blink for a second and then go out when you connect power or does it stay on?
What type of device does your computer see the phone as when you connect it? Please try if you have not. Watch device manager while doing so.
dottat said:
OK. So couple more questions....
Does the power light blink for a second and then go out when you connect power or does it stay on?
What type of device does your computer see the phone as when you connect it? Please try if you have not. Watch device manager while doing so.
Click to expand...
Click to collapse
Power light does not blink at all on connection. This is true both when connecting to a USB power adapter and to the computer.
My computer does not recognize a device. ADB does not report that a device is connected. Also, I use a Mac, so System Information does not report any USB device being connected. For comparison, I tried with my wife's Samsung S5, and it reported correctly in both places, so I know the cable and computer are working correctly here too.
devmage said:
Power light does not blink at all on connection. This is true both when connecting to a USB power adapter and to the computer.
My computer does not recognize a device. ADB does not report that a device is connected. Also, I use a Mac, so System Information does not report any USB device being connected. For comparison, I tried with my wife's Samsung S5, and it reported correctly in both places, so I know the cable and computer are working correctly here too.
Click to expand...
Click to collapse
Can you check dmesg on your Mac and see if you have any qualcomm devices show up near the end of the file? . Plug the phone in right before running the command.
dottat said:
Can you check dmesg on your Mac and see if you have any qualcomm devices show up near the end of the file? . Plug the phone in right before running the command.
Click to expand...
Click to collapse
Nothing from Qualcomm, nor anything related, upon plugging in the phone.
Using
Code:
sudo watch 'dmesg | tail -n 15'
(OS X requires dmesg be accessed with sudo), I saw the following come up upon plugging in the S5 mentioned before:
Code:
USBMSC Identifier (non-unique): 0x00000000 0x4e8 0x685b 0x232, 2
With the same watch in place, I saw no output at all for the M8.
devmage said:
Nothing from Qualcomm, nor anything related, upon plugging in the phone.
Using
Code:
sudo watch 'dmesg | tail -n 15'
(OS X requires dmesg be accessed with sudo), I saw the following come up upon plugging in the S5 mentioned before:
Code:
USBMSC Identifier (non-unique): 0x00000000 0x4e8 0x685b 0x232, 2
With the same watch in place, I saw no output at all for the M8.
Click to expand...
Click to collapse
I would suggest warranty route through HTC. You have got a brick.
dottat said:
I would suggest warranty route through HTC. You have got a brick.
Click to expand...
Click to collapse
That is my fear. Thank you for your help.
dottat said:
OK. So couple more questions....
Does the power light blink for a second and then go out when you connect power or does it stay on?
What type of device does your computer see the phone as when you connect it? Please try if you have not. Watch device manager while doing so.
Click to expand...
Click to collapse
Hi,
Background: Rooted, S-Off (via Sunshine), was running CleanROM (on the 444 firmware) and tried installing Vanir 444. ROM installed no problem, Gapps installed no problem, installed SuperSU 2.40 at the end and rebooted.
I've run into the exact same situation as the OP. Tried all the button combinations/adb stuff and the phone only boots to the initial white HTC screen but then goes blank. I've tried everything to get into bootloader but nothing seems to get me there. The phone vibrates when it "turns on" after the hard reset but nothing after the white HTC screen except a black screen.
I'm responding to this post in particular because my phone was/is showing the blinking power light when it's plugged in. Hopefully this is a good sign?
TIA for any help!
Matt
sigmaxaa said:
Hi,
Background: Rooted, S-Off (via Sunshine), was running CleanROM (on the 444 firmware) and tried installing Vanir 444. ROM installed no problem, Gapps installed no problem, installed SuperSU 2.40 at the end and rebooted.
I've run into the exact same situation as the OP. Tried all the button combinations/adb stuff and the phone only boots to the initial white HTC screen but then goes blank. I've tried everything to get into bootloader but nothing seems to get me there. The phone vibrates when it "turns on" after the hard reset but nothing after the white HTC screen except a black screen.
I'm responding to this post in particular because my phone was/is showing the blinking power light when it's plugged in. Hopefully this is a good sign?
Thanks TIA for any help!
Matt
Click to expand...
Click to collapse
I'm afraid that I won't be of much help going forward. I sent in the device on a warranty claim.
I will add that, in the day or so following my posts here, I plugged the phone in again and to my surprise it began taking a charge again. I let it charge for about an hour, and tried turning it on - remarkably, it came up normally. It was stable for about an hour more, and then froze and powered off as before, refusing to once again turn on.
I left it alone for another couple of days, during which time my replacement arrived, and tried again. It began taking charge, and I left it as such for a couple hours more. This time knowing that my stable time was limited, and with a replacement phone in hand, I immediately restored the phone to RUU stock and locked it.
Your problem seems different from mine, in that my device was outright refusing to even take power or turn on. Best of luck to you, though!
Thanks for the info...I appreciate the response. I'm hoping that there's something that can be done but after 2 hours, trying every trick I could find via
Google with nothing to show for it, I'm keeping fingers crossed that it's something simple I'm missing. If I could just get into the dang bootloader!
Thanks again!
Sent from my SM-P600 using XDA Free mobile app
---------- Post added at 01:38 PM ---------- Previous post was at 01:34 PM ----------
sigmaxaa said:
Hi,
Background: Rooted, S-Off (via Sunshine), was running CleanROM (on the 444 firmware) and tried installing Vanir 444. ROM installed no problem, Gapps installed no problem, installed SuperSU 2.40 at the end and rebooted.
I've run into the exact same situation as the OP. Tried all the button combinations/adb stuff and the phone only boots to the initial white HTC screen but then goes blank. I've tried everything to get into bootloader but nothing seems to get me there. The phone vibrates when it "turns on" after the hard reset but nothing after the white HTC screen except a black screen.
I'm responding to this post in particular because my phone was/is showing the blinking power light when it's plugged in. Hopefully this is a good sign?
TIA for any help!
Matt
Click to expand...
Click to collapse
To add to this, I've let the phone sit for about an hour, untouched, and now the green light is blinking like it does when there's a SMS/email. Pushing the power button doesn't do anything.
devmage said:
I'm afraid that I won't be of much help going forward. I sent in the device on a warranty claim.
I will add that, in the day or so following my posts here, I plugged the phone in again and to my surprise it began taking a charge again. I let it charge for about an hour, and tried turning it on - remarkably, it came up normally. It was stable for about an hour more, and then froze and powered off as before, refusing to once again turn on.
I left it alone for another couple of days, during which time my replacement arrived, and tried again. It began taking charge, and I left it as such for a couple hours more. This time knowing that my stable time was limited, and with a replacement phone in hand, I immediately restored the phone to RUU stock and locked it.
Your problem seems different from mine, in that my device was outright refusing to even take power or turn on. Best of luck to you, though!
Click to expand...
Click to collapse
For what it's worth for anyone that finds this info useful...can't take credit for this as I found it over in the One M8 forum. Thanks to @mpogr
I quote his post: "The problem was that my phone's screen was going blank after the normal boot screen, so I couldn't see when it gets turned off. I was simply pressing the Vol Up + Power for too long, so it would go into full reboot. I just measured the amount of time it was taking to do this (was ~12 seconds). So I pressed Vol Up + Power for ~10 secs, then released those and pressed Vol Down. That finally brought me into Fastboot.
I could have probably gotten the same result by pressing Vol Down + Power, however, the phone screen was blank all the time, so it was difficult to understand when I should have released the Power button to let it go into Fastboot."
I held Power/Vol Up for 10 seconds (as he described) and then let go and immediately held Vol Down only...after about 3 seconds, bootloader screen came up and I was able to get into recovery and restore a backup.
Came home from work yesterday and the Pure XL was dead, said it needed to be charged. Never happened before but I figured whatever and plugged it in and went to sleep. Woke up this morning and powered on the phone and the all white BLU splash screen came up and then the phone went off. Came on again and the all white BLU splash screen came up and went off. Ive tried holding down the power button for over a minute. Tried holding the power button and volume keys to boot into recovery from 10 seconds to 2 minutes, nothing stops it! It just keeps rebooting. This has been my apprehension towards purchasing phones with non removable batteries. The boot recycle happens about every 15 seconds and the phone vibrates everytime it boots up for the past 2 hours. Its getting very annoying and there is no way to make it stop. Any help would be greatly appreciated.
thomasanderson said:
Came home from work yesterday and the Pure XL was dead, said it needed to be charged. Never happened before but I figured whatever and plugged it in and went to sleep. Woke up this morning and powered on the phone and the all white BLU splash screen came up and then the phone went off. Came on again and the all white BLU splash screen came up and went off. Ive tried holding down the power button for over a minute. Tried holding the power button and volume keys to boot into recovery from 10 seconds to 2 minutes, nothing stops it! It just keeps rebooting. This has been my apprehension towards purchasing phones with non removable batteries. The boot recycle happens about every 15 seconds and the phone vibrates everytime it boots up for the past 2 hours. Its getting very annoying and there is no way to make it stop. Any help would be greatly appreciated.
Click to expand...
Click to collapse
Plug it into your computer (you'll notice that there will be a longer black screen in-between the bootloops) and hold down the power button for at least 10 seconds or more, then release it after the next vibration and the white BLU screen shows up. It might take a couple of tries.
If you manage to boot into at least recovery but can't boot into the system, then try clearing your cache/dalvik cache and try rebooting into system again.
If all of the above doesn't work for you, then your boot.img/system has gone bad, and you'll have to flash the stock images with SP Flash Tool (both of which can be found on other posts on this forum).
follow the instructions on the SP flash tool thread... sounds like what happened to me after bad flash... theres a lot of information in that thread that will set you up...
Thanks for the quick replies guys. The PC trick didnt work at all. I just called BLU and asked for a replacement(havent heard back from them ironically). I put the phone in the basement so I wouldnt have to deal with that incessant buzzing every 15 seconds. Eventually the battery died. Since I had it powered off finally, I plugged it in for about 10 minutes to give it enough of a charge to power on but not stay on to buzz for another 2 hours. This time I powered it on using the master reset button combo and was finally able to wipe the cache and restart the phone. Took a good 4 or 5 minutes to boot after that, but everything has been fine since. Really dont know what initially caused the issue, never happened before. Good thing too, cause BLU told me that they would send me a RMA within the hour and I still havent heard from them. Think this will be my last BLU phone. Thanks for the assist.
My phone Is stocked without root or Twrp. And I find my self having a bootloop once a month for an odd reason. This forces me to take bat out and put it back in or just let it loop til battery dies
Sent from my PURE XL using XDA-Developers mobile app
bolanoboyboom said:
My phone Is stocked without root or Twrp. And I find my self having a bootloop once a month for an odd reason. This forces me to take bat out and put it back in or just let it loop til battery dies
Sent from my PURE XL using XDA-Developers mobile app
Click to expand...
Click to collapse
??????
My phone is basically out of the box and I'm getting boot loop problems when I first boot. This happens like once a month
Sent from my PURE XL using XDA-Developers mobile app
This happened to me for first time yesterday. Bought the phone earlier this year and everything worked fine. I restarted the phone because my sound recorder app froze up twice on open and the infinite boot started until the battery died. Tried the {power}{vol up} thing, didn't work to stop it, so I put it in my car and went back to the conference I was attending. Battery was dead when I got out. Contacted BLU by phone and they started a ticket for me, but I figured I'd see if other people were having this issue and learn what they did because I'd rather not be out of a phone for however long it takes for BLU to replace mine. Stumbled on this page. I never rooted my phone. And BLU only sent one wireless update since I've had the phone. I'm trying to get into the menu by connecting to the computer. Worked the first time, I cleared cache, and tried to backup my files, but I'd taken out the SD card in expectation of sending it to BLU. So, Powered off the phone, put the card back in, and now I haven't been able to get the menu back. Still working on it, if there are any suggestions anyone drops on me before Tuesday when I'll likely ship it (or at least hope to because I'll be yelling at them Monday), I'd appreciate it.
Update
num1greeter said:
This happened to me for first time yesterday. Bought the phone earlier this year and everything worked fine. I restarted the phone because my sound recorder app froze up twice on open and the infinite boot started until the battery died. Tried the {power}{vol up} thing, didn't work to stop it, so I put it in my car and went back to the conference I was attending. Battery was dead when I got out. Contacted BLU by phone and they started a ticket for me, but I figured I'd see if other people were having this issue and learn what they did because I'd rather not be out of a phone for however long it takes for BLU to replace mine. Stumbled on this page. I never rooted my phone. And BLU only sent one wireless update since I've had the phone. I'm trying to get into the menu by connecting to the computer. Worked the first time, I cleared cache, and tried to backup my files, but I'd taken out the SD card in expectation of sending it to BLU. So, Powered off the phone, put the card back in, and now I haven't been able to get the menu back. Still working on it, if there are any suggestions anyone drops on me before Tuesday when I'll likely ship it (or at least hope to because I'll be yelling at them Monday), I'd appreciate it.
Click to expand...
Click to collapse
I tried to flash the phone, but the bootloop apparently wouldn't allow that. I had 0.0% progress after 3 hours. I then tried to go back into the menu you get from {Power}{Vol UP}: still no go. So, I started to take the phone apart again to get ready for shipping. The battery was still low so it didn't take long for it to die after I unplugged it from the computer. Out of curiosity, I tried to repeat finding the menu like I did earlier that day (conditions were that the phone had no charge when I connected it to the computer, and my SD card was removed.) No go. But, then I hit {Power}{Vol Up}{Vol Down} just to see what happened, and boom. My phone loaded up. No loop... Figured somehow the files had copied and the status bar was wrong. Turned the phone off, put my SD card back in and turned the phone on. Loop reappears ...I waited for the phone to die again, took out the SD, attempted to turn it on and the loop was there. Connected it to the computer and hit all 3 buttons, and the phone loads up. So, now I'm confused. Is there any way that the problem is some crappy connection to the SD?
I've had this phone for about 2 months now, and from the beginning, it's had an issue where it would randomly freeze, restart, and get stuck in a boot loop for random amounts of time. Sometimes it would be fine after 2 minutes, sometimes it would need 10. I kept thinking this was a firmware issue - the phone WAS rooted with TWRP installed, but none of my past phones have had this issue and hardly anybody online seems to have had it, either - and just thought that maybe installing a custom ROM would fix it, but never got around to doing so.
3 days ago, my S7 went into a boot loop again, so I just decided to put it down and let it do its thing. After 20 minutes, however, it still wasn't booting, so I booted into TWRP, and cleared the cache and Dalvik cache. Another 20 minutes later, I went into panic mode and started doing Nandroid backups of my stuff. I decided that I had no other choice but to commence with finding a ROM to replace stock. In the meantime, I just plugged it in and let it keep looping, hoping against hope that it would just fix itself like it always did.
About half an hour later, I was ready to install the ROM I'd decided on. I went and picked up my phone, but all that I saw was the screen was black, and the blue notification LED was lit up. I tried holding Vol- + Power to start booting it into TWRP, but nothing happened. The phone didn't vibrate, the screen didn't change, and the LED stayed lit. I tried holding every button combination possible, for even as long as a minute, but the phone refused to respond. I tried plugging it into my computer, but Windows didn't detect anything.
Skip to today, and the phone's battery has long since died(the LED isn't lit up, so I can only assume...), and I just decided to plug the phone in for the hell of it just to see if maybe it would maybe work again. To my astonishment, 2 minutes later, the battery icon came up on the screen, but the charging animation wasn't there. When I held Vol- + Power, the phone actually responded and restarted! Though, it wouldn't boot past the Galaxy S7 splash screen, and when I tried to boot it into TWRP, it went back to being a brick. I let it sit for about 10 minutes, plugged it in, and this time tried to get it into Download Mode, and it worked!
I downloaded the Switzerland version of the G930F firmware, flashed it in Odin, and everything seems to have worked. Odin says it succeeded, but when the phone tried to restart, it got to the splash screen, and after a few minutes, the screen went black again. When I plug it in now, the Galaxy S7 screen will come up, but now I can't seem to get into Download Mode anymore(though, it DOES still seem to respond to me pressing Vol- + Power).
Does anyone have any idea what's going on? I can only seem to find 3 or 4 other threads on various forums about this problem, but none of them have any answers. People just keep saying the usual "Hold Vol- and Power to make the phone restart", but in case I haven't made it clear, THAT ISN'T WORKING.
And before you suggest that I return it to where I bought it for a replacement or refund: I bought this phone on eBay from a seller who said it was in pretty much mint condition. When the phone arrived, there was not a dent or scratch anywhere on the phone, even around the charger port, so I have no reason to believe he was lying. When I asked him about any possible problems with the phone's operational stability the other day, he says he tested it for about 2 weeks, and that he didn't notice anything.
Sounds like a hardware fault, not much else you can do other than flashing stock and factory resetting, which you've done
Considering it had a fault from day 1 it sounds like that fault finally caught up with it
Likely scenario if sent for repair, new motherboard replacement needed