Develop Bugs

HELP!!!! WiFi connection unstable and SDCard unmounting automatically

Hi All,
I own a LG G3 for past 1 yr and 4 months. Every thing was fine until last month when I accidentally dropped my phone and the display cracked. Of course, touch did not work. So last week I went to an authorized LG service center to change the whole display (which involves the process of taking out the motherboard and fixing it with another display. This means the whole frame is changed). He did this process in front of me only. After the change, everything works well except for a weird WIFI problem which I never faced before the screen was replaced.
The WIFI would frequently connect and disconnect. Even in the search list, all the SSIDs would be shown occasionally and sometimes won't show up at at all. Note again, this happens with all the potential WIFI connections around, Not only with mine. In short, the WIFI search results list won't be stable.
Even if my WIFI shows up in the list and I try to connect it will show - "saved"/"disconnected"/"Disabled" status. And yes, occasionally my WIFI gets connected and internet starts working. But not for too long. Prolly the connection lasts for 5-10 mins or so. All my other devices connect using the same AP and so i don't really have a doubt on my router AP.
I visited the authorized service center again. Without even having looked at the problem he says motherboard might be the problem, and asked me to change it. Even if i persist him to have a look at the problem, he won't . My last resort is XDA
The ways I tried.
1. Factory reset.
2. Flashed roms 21A and 20P (from scratch, erased all data and caches). Still No joy.
3. Tried forgetting the network and connecting again.
4. Toggle WiFi on and off
P.S : I also have another problem of SD card getting unmounted automatically and an error message pops up as "SD Card removed unexpectedly. Please unmount SDCard before removing to prevent", but immediately a toast message comes as SD card inserted. xx.xx GB space available. This keeps on happening in a loop until SD Card wouldn't show up in File manager at all. But, this problem was there for a long time even before the screen was replaced unlike the WiFi
problem which occurred only after the screen is replaced.
I really don't know what exactly is going on with my phone. Please let me know if any of you are familiar with these problems and have solved it. Would really save a huge money for me

Cellular data loss (radio reboot?)

https://www.reddit.com/r/GooglePixel/comments/5b6twj/pixel_xl_intermittent_cell_and_gps_signal/
https://www.reddit.com/r/GooglePixel/comments/5bhltm/issue_with_dropping_lte_service_randomly/
Hello all,
I am currently attempting to troubleshoot/corroborate apparent issues with the mobile radio. My first device took six or seven attempts to activate, and then intermittently threw a no SIM error with what looks like a radio restart (no signal on any bands, cycle between No Service/Searching 4-5 times before reconnect.)
WiFi appears to be good, I'm only experiencing these drops while connected to LTE with no graceful fallback to 3g or even 1x. Drops are happening while stationary and in motion, frequently in areas where my signal is at least decent. The threads linked above both have users who appear to be having the same problem. Particularly strange is that there dose seem to be a location component, there are two spots in particular that seem to be more likely to cause the problem (though not every time.)
I've replaced the device once already in an attempt to resolve this, and while I initially thought that the issue was resolved, I did manage to catch another drop yesterday after running tests forcing the device in to 3g-only operation (the device performed just fine before, during, and for a few minutes directly after these tests.) Of note, I haven't managed to catch a 'No SIM' message on this replacement phone. I have been running an app to notify me of signal loss today, and of course it seems to be behaving now.
If you've experienced any similar issues, please reply and let me know if you've had luck resolving.

Yep this is what is happening allright.
I have two htc one M7s. My main phones.
Last evening, in a very strange shift from her norm, my woman asked to use MY phone to cruise the net.
Ok so she goes on and fifteen minutes later I get the phone back.
Suddenly, in the middle of refreshing a twitter or facebook, THE WI FI CONNECTION GOES DOWN.
I cant get the thing to reset after shutting it off. I have to go to the ROUTER , turn it off then on.
Five minutes later after ROUTER reboot, it is working again.
It is just the beginning of our story. I have a second phone also same make and model. It is midnight now, some four hours later, and as usual I turn off router before sleep.
I wake up, unplug other phone (not the one from last night) and, swap out the sim card to it (was in phone durring Wi Fi problem).
Now, I switch on the phone, and it comes up with LTE cuz Im on mobile. Then I get the normal "ok" from phone message (system communicating with mobile).
Heres where it gets strange. I get the 3G on top bar. Ok this NEVER happens.
One minute later it says LTE again.
Wtf is happening.
Not mentioning in this story little invisible forces kicked my left leg open as I was waking up. Angry *****es over Hillary.

Same LTE issue here. Just contacted Google Support and rebooted to safe mode. Let see if I have the same problem again tomorrow

chadwick359 said:
https://www.reddit.com/r/GooglePixel/comments/5b6twj/pixel_xl_intermittent_cell_and_gps_signal/
https://www.reddit.com/r/GooglePixel/comments/5bhltm/issue_with_dropping_lte_service_randomly/
Hello all,
I am currently attempting to troubleshoot/corroborate apparent issues with the mobile radio. My first device took six or seven attempts to activate, and then intermittently threw a no SIM error with what looks like a radio restart (no signal on any bands, cycle between No Service/Searching 4-5 times before reconnect.)
WiFi appears to be good, I'm only experiencing these drops while connected to LTE with no graceful fallback to 3g or even 1x. Drops are happening while stationary and in motion, frequently in areas where my signal is at least decent. The threads linked above both have users who appear to be having the same problem. Particularly strange is that there dose seem to be a location component, there are two spots in particular that seem to be more likely to cause the problem (though not every time.)
I've replaced the device once already in an attempt to resolve this, and while I initially thought that the issue was resolved, I did manage to catch another drop yesterday after running tests forcing the device in to 3g-only operation (the device performed just fine before, during, and for a few minutes directly after these tests.) Of note, I haven't managed to catch a 'No SIM' message on this replacement phone. I have been running an app to notify me of signal loss today, and of course it seems to be behaving now.
If you've experienced any similar issues, please reply and let me know if you've had luck resolving.
Click to expand...
Click to collapse
I've got a Black 32GB XL on Verizon (Verizon Model) and never have this problem. Any tips on reproducing it? I'd love to help test and see what I can come up with. Only time my phone says no-sim is for like 5ish seconds after boot. And I've only once seen the phone fall to 3g in an area with known strong LTE. My previous note 7 fell off LTE pretty often. Specially when jumping between towers. But my PXL rarely (Once) does.

This has been happening to me on my pixel xl 128gb since the day I got it. I reported it to Verizon and to google. Google said bad sim. Verizon replaced my sim and it didn't change a thing. I can usually get it to reconnect if I toggle cellular data on and off. Please let me know if anyone finds a solution.

This is known as hollow bar. And it happens to certain Nougat phones in certain areas.

New Unlocked S8+ 955U service issue after flying

Recently purchased a new, unlocked S8+ and got a new SIM from Verizon. This was approximately 2 weeks ago. Zero problems up until this week. I have been on 4 flights this week - before each flight, the phone works great. When I land on the other end, Verizon LTE pops right up, varying numbers of bars as one would expect depending on arrival airport, just like it would normally when I have service and can do everything. However, nothing. No texts, no calling, no data. Tried toggling various things, resetting, nothing for a hour after that, all the while I've got 3-4-5 bars and I can see the data arrows lighting up like there is upload/download transfer.
Finally, I tried "reset network settings" as a last resort and immediately my phone works like a charm. It has happened another 3 times since - every time I have flown, with the exact same results.
All domestic flights. While I'm not a guru, I'm not a complete halfwit either - this is my 4th galaxy and it's definitely not something I'm doing or have ever had problems with before. I fly all the time and never a problem like this until this week. Checked APN, it's right. Checked software update - have most recent.
Any ideas? I'm desperate. Have searched literally everything I can think of and no one else seems to be reporting this problem, not to mention it's difficult to describe in a Google search. About at my wit's end having to re-enter wifi and passwords every day, relearn Bluetooth devices. Theres no other way to truly reset the mobile data settings and get my phone to work that I've discovered. Please, please help.

Eject SD card and remove sim, wait a min, reinsert cards. While the phone is on. Should reset just ur sim settings. Maybe

Help! Verizon Note 4 random network drop...

I apologize in advance for the long read.
I recently activated Verizon service on a Note 4 that has been sitting unused since the Note 8 came out. The Note 4 is in perfect physical condition, with no scratches on the screen or body, and has been in a protective case since new. I did replace the battery in it prior to activation, as I expect for the life to have been deteriorated.
I did a factory reset and inserted my Verizon SIM card, and it worked perfectly. I installed my everyday apps and a few games on the phone, and I used it without any issue for about a week. During that time, it did install a couple of OTA updates, but I expected that since it had been "off service" for a few years.
After that first week, I put the SIM card back in my NOTE 8 for a couple of days, after which I went back to the Note 4. Initially, 4G data and cell service worked, but within the same day I started having service drops. If I was on the phone and a call dropped, it would show an error message saying "No SIM / SIM Error".
Her is what I have attempted so far:
First, I replaced the SIM with a new one. There was difference in the frequency of the random service drop.
When that did nothing, I assumed that one of the OTA updates from the prior week had done something to modem / radio. The phone was on 6.0.1 at that time. I unlocked the bootloader and installed TWRP, and first tried downgrading to stock 5.1.1, then to a "modified 5.1.1, then to CM 13, and now Lineage 15 (frequently factory reset / cache wipe. There has not been an improvement (or reduction) to the random service drop.
Yesterday, I happened to be on My Verizon online, and I had a message showing that Verizon no long had the information on my phone (IMEI), and requesting that I open a Chat Window to update my info. At this point, the Note 4 is still running the Lineage 15.1. The Verizon team member asked me for the IMEI, and when I looked under the settings, it said "None" under IMEI. In a quick search, I found a forum on Lineage 15.1 that said turning of the screen lock and rebooting the phone will reload the SIM and IMEI info. That worked, and I was able to view the IMEI and verify connection. I explained my issue with the Verizon support, and she said everything appeared to be good on her end. Over the course of 15 minutes, we tested my connection and it worked. About 30 minutes after that, it dropped service again.
Finally, here is where it is at now:
I start with no service. If I do nothing but restart the phone, it will show LTE service for 2 or 3 seconds, then nothing. If I remove and reinstall the SIM, I will get the same 2 or 3 seconds, then nothing. If I turn Airplane Mode on and off, that does not reconnect the service. If I change the lock screen security to "None" and restart the phone, there is no service, but if I set Screen Lock to "Swipe" and restart the phone, I will have LTE service for at least 30 - 45 minutes before it drops, sometimes a few hours. When it does drop, it does not come back on it's own. The only way I have found to get it back it to "Screen Lock - None, reboot, Screen Lock - swipe, reboot".
Will replacing the modem fix the problem? Is there a specific modem that I need to match up to the ROM? Thanks!

bife2003 said:
I apologize in advance for the long read.
I recently activated Verizon service on a Note 4 that has been sitting unused since the Note 8 came out. The Note 4 is in perfect physical condition, with no scratches on the screen or body, and has been in a protective case since new. I did replace the battery in it prior to activation, as I expect for the life to have been deteriorated.
I did a factory reset and inserted my Verizon SIM card, and it worked perfectly. I installed my everyday apps and a few games on the phone, and I used it without any issue for about a week. During that time, it did install a couple of OTA updates, but I expected that since it had been "off service" for a few years.
After that first week, I put the SIM card back in my NOTE 8 for a couple of days, after which I went back to the Note 4. Initially, 4G data and cell service worked, but within the same day I started having service drops. If I was on the phone and a call dropped, it would show an error message saying "No SIM / SIM Error".
Her is what I have attempted so far:
First, I replaced the SIM with a new one. There was difference in the frequency of the random service drop.
When that did nothing, I assumed that one of the OTA updates from the prior week had done something to modem / radio. The phone was on 6.0.1 at that time. I unlocked the bootloader and installed TWRP, and first tried downgrading to stock 5.1.1, then to a "modified 5.1.1, then to CM 13, and now Lineage 15 (frequently factory reset / cache wipe. There has not been an improvement (or reduction) to the random service drop.
Yesterday, I happened to be on My Verizon online, and I had a message showing that Verizon no long had the information on my phone (IMEI), and requesting that I open a Chat Window to update my info. At this point, the Note 4 is still running the Lineage 15.1. The Verizon team member asked me for the IMEI, and when I looked under the settings, it said "None" under IMEI. In a quick search, I found a forum on Lineage 15.1 that said turning of the screen lock and rebooting the phone will reload the SIM and IMEI info. That worked, and I was able to view the IMEI and verify connection. I explained my issue with the Verizon support, and she said everything appeared to be good on her end. Over the course of 15 minutes, we tested my connection and it worked. About 30 minutes after that, it dropped service again.
Finally, here is where it is at now:
I start with no service. If I do nothing but restart the phone, it will show LTE service for 2 or 3 seconds, then nothing. If I remove and reinstall the SIM, I will get the same 2 or 3 seconds, then nothing. If I turn Airplane Mode on and off, that does not reconnect the service. If I change the lock screen security to "None" and restart the phone, there is no service, but if I set Screen Lock to "Swipe" and restart the phone, I will have LTE service for at least 30 - 45 minutes before it drops, sometimes a few hours. When it does drop, it does not come back on it's own. The only way I have found to get it back it to "Screen Lock - None, reboot, Screen Lock - swipe, reboot".
Will replacing the modem fix the problem? Is there a specific modem that I need to match up to the ROM? Thanks!
Click to expand...
Click to collapse
I think you might be dealing with 2 separate issues. I'm kind of guessing about the first issue but the second is a common problem.
I think the original problem is that your sim card is not making a good contact in the sim slot. You could try putting a think piece of cardboard or something that will press the sim card to the sim slot contacts (maybe check to make sure that there isn't any dirt on the contacts but from the sound of it I'm guessing your phone is pretty clean).
The second problem is that all of the aosp roms have varying degrees of signal loss that occurs. Some people have a lot and some not as much, but everyone is affected in some way with what people have been referring to as "sim death".
My suggestion would be to run a stock or modified stock rom until you get your sim problem straightened out and then if you still want to switch to an aosp rom then at least you'll know that any further problems are just the normal sim death that occurs from time to time with those types of roms.
If you've already updated your bootloader to a 6.0.1 version you can flash the modified stock rom that I put together. I haven't had any signal/sim issues at all with that and no reports of it. Like I mentioned before though, the only caveat is that it needs to be on a bootloader that is at least CPD1 or newer. If it's not then your wifi won't work.
Rom link If you're interested.

kevintm78 said:
I think you might be dealing with 2 separate issues. I'm kind of guessing about the first issue but the second is a common problem.
I think the original problem is that your sim card is not making a good contact in the sim slot. You could try putting a think piece of cardboard or something that will press the sim card to the sim slot contacts (maybe check to make sure that there isn't any dirt on the contacts but from the sound of it I'm guessing your phone is pretty clean).
The second problem is that all of the aosp roms have varying degrees of signal loss that occurs. Some people have a lot and some not as much, but everyone is affected in some way with what people have been referring to as "sim death".
My suggestion would be to run a stock or modified stock rom until you get your sim problem straightened out and then if you still want to switch to an aosp rom then at least you'll know that any further problems are just the normal sim death that occurs from time to time with those types of roms.
If you've already updated your bootloader to a 6.0.1 version you can flash the modified stock rom that I put together. I haven't had any signal/sim issues at all with that and no reports of it. Like I mentioned before though, the only caveat is that it needs to be on a bootloader that is at least CPD1 or newer. If it's not then your wifi won't work.
Rom link If you're interested.
Click to expand...
Click to collapse
Thank you for the reply. I think that you may be onto something with both issues. After posting this question today, I did examine the SIM slot, and although all of the pins looked good, and no dust or debris was visible, the metal guide over the SIM did feel slightly loose from the card. I did put in a thin shim, and the significantly improved the time that the phone stays connected. If that was a true issue, along with the possibility of the ROM causing a separate cause, I am absolutely interested on going back to a stock (or modified stock) ROM. The only reason that I did what I did was an attempt to fix the connectivity issue.
Thanks for your help. I will give your ROM a try and let you know how it works.

Question SM-F926U1 no longer seeing/using SIM card?

Hi everyone, just a little curious on what side of the old "metaphorical" coin my phone has fallen on. The problem this coin is concerning, is simply one related to my SIM. My phone has no cell service right now since it doesn't want to acknowledge or use the sim card it has in it. It's a 512Gb unlocked phone I special ordered upon first release, no other problems (other than the screens scratching easily) but now it's no longer working on anything other than wifi. It's the wifi that I think caused this problem actually. I just set up a new lightweight Asus RT-AX56U router to utilize two WAN ports (one built in and the other setup through a USB ethernet adapter). The problem came about after I switched down to a WPA3/WPA2 setup from a full WPA3 simply due to a connection problem one of my laptops was having (it's wifi card was one from prior to WPA3). Shortly after I did that my Z Fold 3 started having frequent wifi drop problems. After about an hour of that the connection seemed stable, then the next thing I know the phone dropped connection to both Wifi and cell network! Then after I restarted the router, only wifi would reconnect and my cell network connection has been M.I.A. ever since despite what I do (tried airplane mode, tried cache whipping it, restarting it, and finally even a full factory wipe/restart). My phone is up to date on all of it's updates (finally decided to last month after seeing that my model has no root + camera options) but nothing other than a routen cache cleaning ever happened to it prior. Just trying to figure out what my next move now should be, get a new SIM card, or is a whole new phone needed?

I would first try another sim card to see it's related to the physical card or a carrier issue. Maybe try and borrow one from another network as well.
If that fails, try a factory reset.
If that fails, it's time to reach out to Samsung.

I tried a different SIM from a different phone from the same provider (on the same contract bill). But it wouldn't register, I even factory reset it prior to trying the other SIM. So I went and got a new one from the carrier, and problem solved! (First SIM card I've ever burned out without truly trying to)