no cell service after IMEI repair - Nexus 5 Q&A, Help & Troubleshooting

i accidentally wiped the IMEI off of my nexus 5 when trying to repair my EFS partion (which was corrupt at the time), since i had the original value on a sticker on the back i tried to repair it. i finally managed to repair it by reflashing the radio image, then using the qualcom nv tools to write it back. my main problem is i cannot connect to the mobile network (which is at&t) after the repair, i reflashed the stock rom and updated it to the latest version (i used android lollipop in the repair process), then i manually set the APN settings according to at&t support page and still no luck. is there anyway to restore my mobile connection?

I have no clue if my suggestion is valid in this situation or not, but I know there are root apps and Xposed modules that can change IMEI. Perhaps you can try one of those to re-apply the IMEI to the system? Sadly I have no experience with doing this myself. Note that if you try this it will apparently erase various data.

I am aware of the xposed modules, however they are only temporary and need to be set each time you switch to a new ROM. in my case I plan to switch to Ubuntu touch or Sailfish OS when I get everything working again, which xposed does not work on. I did make a permanent change via the qualcom nv tools, but I am beginning to think I erased more than the IMEI. I know the MIED is only a few characters short of the IMEI, so thats restored, but I ended up with an ESN being written to the device even though I had not entered one. I am not sure if it was randomly generated somehow or if there is a way to figure out what the ESN should be from then IMEI. I also heard of baseband data being stored in the EFS partition, although I did flash a radio image to it prior to writing the IMEI and i think a radio image would likely have that data. I have no idea about the other types of data that a radio image wouldn't contain that would be essential to connecting. Any ideas?

Related

[Q] Nexus 5 Possible EFS issue, IMEI already repaired

First post, long time lurker, so i'll start with a big thanks to the entire community for all the help you've unknowingly given me.
I just got a nexus 5 to replace my original n5 which has a broken screen. I took a backup of the original and restored it to the new one. Unfortunately i didn't know what EFS was, so i restored the old EFS to the new phone. IMEI went to zero. HUGE BUMMER.
I was able to fix the IMEI with QPST, but the new phone will not connect to the network. I've run a check on the IMEI and it is not blacklisted. Without incriminating myself, lets just say that i'm positive that the new IMEI is good.
The phone recognizes that i've inserted a SIM but shows no signal. I've tried to search for networks, i've checked the APN settings...
I REALLY don't want to send this to LG since they can't give me a price or even a ballpark figure without me shipping them the phone...
Any advice on next steps would be greatly appreciated.
What should i try next?!
flash the factory img and do not restore your efs on it.
simms22 said:
flash the factory img and do not restore your efs on it.
Click to expand...
Click to collapse
I guess i should have mentioned that i've flashed factory also. Currently the phone is on the latest firmware, unrooted, locked bootloader. Flashing factory had no effect at any point.
I bought this phone on Swappa BTW, so i am assuming there are no hardware issues. I'm not at all certain what else may have been screwed up by having another phone's EFS restored over this "new" phone's EFS...
More Info
I am able to attempt to manually select the network. When i search for networks, the available networks are shown, but when i try to connect it shows the Registering dialog for quite a while, then fails. This is the same behavior as a working phone without a SIM installed. The odd part is that the phone will recognize when a SIM is installed or removed. It seems that my problem may be that the SIM is not being read properly or the data is being lost/corrupted between SIM and antenna. Is this possible? Is this EFS corruption? is this something i can fix? Please help.
Bump?

MI4C IMEI/Baseband unknown

Hi guys!
Yesterday my firmware update went terribly wrong and now I have a device that states that imei and baseband are unknown, so I my both sim-cards don't work.
I've tried several types of IMEI restoration, but none of them worked.
Unfortunately I don't have any backup for nvram. So, my guess is that there is a problem with EFS partition on the phone.
In QPST NV RF Manager I see my real IMEI from the box, so I guess it is still present, but my baseband doesn't work. Can you please suggest any help on recovering the baseband? Or if it is possible share with me modem backup or nvram backup without IMEI (I've seen on this forum that one guy with Samsung S3 had a kind of the same problem and he was given a working nvram backup without IMEI (IMEI was 0/00)) I can write my IMEI then, if baseband works again. Will appreciate any help.
Send it back. Only the oem is legally able to mess with the IMEI.
zelendel said:
Send it back. Only the oem is legally able to mess with the IMEI.
Click to expand...
Click to collapse
Well... I have managed to make it work again and my original IMEI is back. The only thing I had to do is to restore a working NVRAM backup (from another device) via QPST. So, it wasn't that hard. Much simpler than sending it back to China.
landslider said:
Well... I have managed to make it work again and my original IMEI is back. The only thing I had to do is to restore a working NVRAM backup (from another device) via QPST. So, it wasn't that hard. Much simpler than sending it back to China.
Click to expand...
Click to collapse
If you restored the file from another device then it won't have the right IMEI.
zelendel said:
If you restored the file from another device then it won't have the right IMEI.
Click to expand...
Click to collapse
It HAS right IMEI, I checked it with the original box. No need to put up an argument about it. Both devices (mine and the one which was backupped and restored from) are working fine, bot have ORIGINAL IMEI numbers and no errors considering networks or MI accounts. So, actually I have no idea what you are trying to tell me.
landslider said:
It HAS right IMEI, I checked it with the original box. No need to put up an argument about it. Both devices (mine and the one which was backupped and restored from) are working fine, bot have ORIGINAL IMEI numbers and no errors considering networks or MI accounts. So, actually I have no idea what you are trying to tell me.
Click to expand...
Click to collapse
I'm not making an argument. I'm trying to figure out how a number which is supposed to be hard coded into the file is then restored by restoring the files from a different device.
As these devices are not sold in the states learning as much as possible is a good thing.
Glad you got it working.
zelendel said:
I'm not making an argument. I'm trying to figure out how a number which is supposed to be hard coded into the file is then restored by restoring the files from a different device.
As these devices are not sold in the states learning as much as possible is a good thing.
Glad you got it working.
Click to expand...
Click to collapse
Okay, sorry. I will try to make it a bit clearer=) This device is not sold in Russia either (officially at least), so the only way to get it is to buy from aliexpress or ebay or anything else. In that case the buyer doesn't get any guarantee or official support. So if the device is broken and can't be restored it turns into a garbage. I believe that in the US the situation with that kind of devices is almost the same.
Now, if You are not familiar with QPST it is a software package for qualcomm based devices which can make backup/restore of some non-firmware software from the device (like IMEI, ESN, Baseband, LTE Channels etc). As for IMEI number, basically, as You've said it is hard coded into device so it is pretty hard to get it changed or fully deleted. Here we come to my case of unknown Baseband and IMEI. Though via phone settings I could see: "Unknown", my IMEI didn't change and was stored in the device. The "error" or smth like that happened after the factory reset and my guess is that the file structure of NVRAM was changed. So, backup of NVRAM taken from the working device didn't actually have IMEI or ESN in it, but it has the right file structure without any errors. That is what happened, the file structure was restored without changing any factory numbers.
If you have any questions, feel free to ask
landslider said:
Okay, sorry. I will try to make it a bit clearer=) This device is not sold in Russia either (officially at least), so the only way to get it is to buy from aliexpress or ebay or anything else. In that case the buyer doesn't get any guarantee or official support. So if the device is broken and can't be restored it turns into a garbage. I believe that in the US the situation with that kind of devices is almost the same.
Now, if You are not familiar with QPST it is a software package for qualcomm based devices which can make backup/restore of some non-firmware software from the device (like IMEI, ESN, Baseband, LTE Channels etc). As for IMEI number, basically, as You've said it is hard coded into device so it is pretty hard to get it changed or fully deleted. Here we come to my case of unknown Baseband and IMEI. Though via phone settings I could see: "Unknown", my IMEI didn't change and was stored in the device. The "error" or smth like that happened after the factory reset and my guess is that the file structure of NVRAM was changed. So, backup of NVRAM taken from the working device didn't actually have IMEI or ESN in it, but it has the right file structure without any errors. That is what happened, the file structure was restored without changing any factory numbers.
If you have any questions, feel free to ask
Click to expand...
Click to collapse
It is almost the same with a few exceptions. One being that their devices are banned from all people that work for the government, sometimes they get stopped at customs due to copyright issues and with the latest news about them coming loaded with malware, most won't buy them.
That makes sense in a way. Not sure why a factory reset would mess up that part of the device as it shouldn't touch it.
Thanks for the info.
zelendel said:
Not sure why a factory reset would mess up that part of the device as it shouldn't touch it.
Click to expand...
Click to collapse
I don't know either, but it was an unforgettable experience and a lesson to do backups of everything.
Hi @landslider, what's up friend? I have the same problem but I have no backup hidden partitions. Could you help me fix my device?
harolete said:
Hi @landslider, what's up friend? I have the same problem but I have no backup hidden partitions. Could you help me fix my device?
Click to expand...
Click to collapse
Hi! Have you tried flashing China developer rom with Miflash?
Second option: Connect to your PC and run QPST according to one of the manuals (in order for your phone to show up as a COM), run RF NV Manager and look up your line 550 NV_IMEI if it is filled with numbers that are the same as on your box (check HEX above them and numbers should resemble yours from box but written in opposite direction, eg: on the box it is XXXX69XXXXX in the QPST it will be 96). So, if your IMEI is at its place than all you need is a working device from someone to make a backup. Backup must be made in newer versions of QPST in *.xqcn format and than restored to your phone with checked box "allow ESN mismatch"
landslider said:
Well... I have managed to make it work again and my original IMEI is back. The only thing I had to do is to restore a working NVRAM backup (from another device) via QPST. So, it wasn't that hard. Much simpler than sending it back to China.
Click to expand...
Click to collapse
Could you teach me how to do that? how can i make nvram backup via other mi4c? and how can i put it into my mi4c ?? as i am not good at computer so i need your detailed explanation. I would be very glad if you help me.....
landslider said:
Okay, sorry. I will try to make it a bit clearer=) This device is not sold in Russia either (officially at least), so the only way to get it is to buy from aliexpress or ebay or anything else. In that case the buyer doesn't get any guarantee or official support. So if the device is broken and can't be restored it turns into a garbage. I believe that in the US the situation with that kind of devices is almost the same.
Now, if You are not familiar with QPST it is a software package for qualcomm based devices which can make backup/restore of some non-firmware software from the device (like IMEI, ESN, Baseband, LTE Channels etc). As for IMEI number, basically, as You've said it is hard coded into device so it is pretty hard to get it changed or fully deleted. Here we come to my case of unknown Baseband and IMEI. Though via phone settings I could see: "Unknown", my IMEI didn't change and was stored in the device. The "error" or smth like that happened after the factory reset and my guess is that the file structure of NVRAM was changed. So, backup of NVRAM taken from the working device didn't actually have IMEI or ESN in it, but it has the right file structure without any errors. That is what happened, the file structure was restored without changing any factory numbers.
If you have any questions, feel free to ask
Click to expand...
Click to collapse
so can you please upload that xqcn file from the working device ? i have the same issue and i can't find a working mi4c inn my area !
spybit2008 said:
so can you please upload that xqcn file from the working device ? i have the same issue and i can't find a working mi4c inn my area !
Click to expand...
Click to collapse
Hi! Unfortunately no, I can't. I don't have xiaomi mi4c anymore
spybit2008 said:
so can you please upload that xqcn file from the working device ? i have the same issue and i can't find a working mi4c inn my area !
Click to expand...
Click to collapse
http:/ en.miui.com thread-315233-1-1.html (replace whitespaces with slash)
There is a thread in official forum where one guy shares qcn backup. There is also an instruction to restore IMEI and baseband. But It doesn't help for me. Network still unavailable.

help needed - S6 IMEI/BASEBAND UNKNOWN -

Hello dear ones, I'm lost and I need your help.
I've bought a used SM-g920f, knox x0. It worked flawlessly. Until the first evening when in the middle of a phone call the phone app crashed. After resetting the phone it was still unable to connect to network. I have noticed that baseband/IMEI were set to unknown and so it could not read my sim card.
First I have tried the obvious - upgrading from lollipop to marshmallow. It went easy but did not help. Neither did help resenting to factory settings.
I have rooted and installed twrp recovery adb and stuff.
After almost two days playing with it, I seem to be out of options.
What I tried:
Flashing Different roms - stock and non-stock. (G920FXXS3DPB2_G920FXEU3DPB1_G920FXXS3DPB3_HOME, G920FXXS3DPB2_G920FOXX3DPB2_G920FXXS3DPB3_HOME, Pure-Stock.ExtraLiteROM_XXU3DPCA.DEODEX-v5.5.by.ambasadi, XtreStoLite-ROM-3.0-Final-DPCA) - I do not know the country of origin of this device. (the back is from testing unit), is there some way to know correct original stock ROM ?
Flashing Different modems - (G920FXXS3DPB1_Modem_TWRP, G920FXXU3DPB6_Modem_TWRP, G920FXXU3ZPA1_Modem_TWRP)
Checked sim card in another phone/different card in this phone - if sim card would be invalid, would I still get missing baseband?
Xposed Imei Changer - it did change IMEI. But that's it. Baseband still missing.
*#0011# and other *# stuff..
And I have wiped /efs (it did generate new nv_data. Guess now even broken IMEI would make ma happy)​
Any ideas ?
How can I know what can be wrong? /efs partition? wrong firmware combination? hardware issue?
In Samsung Phone Info I get empty on Modem Board, Hardware Revision,Samsung Serial Number,Baseband Version.
Than you for any help or idea!
tried smart Switch emergency reinitialization?
Just to be sure, knox is triped now?

[Completed] Nexus 6 No LTE with correct IMEI! "0" Imei and LTE!

Ok, Ladies and Gentleman I need some deep thought processing here for some help with a Motorola Nexus 6. In brief here is what the problem is, a while back when flashing Pure Nexus rom, I experienced a loss of my IMEI. I can restore my IMEI but if and when I do, I lose any 4g and LTE connectivity. The phone functions in 3g with data and phone etc... just slow as molasses but if I restore my IMEI to the one that doesn't show up my IMEI correctly I get back LTE/4g and all works fine also. I've tried going all the way back to the original firmware which was saved to computer and restoring it. Same thing, I have IMEI but no LTE/4g. restore bad efs and get LTE/4g back. I've tried going through all the factory firmware's and flashing by ADB and or TWRP and nothing firmware wise will allow me to restore the IMEI and have LTE/4g signal. If I restore the bad efs and get OOOOOOOO for IMEI when using the *#06# on any firmware version, I regain LTE/4g functioning! I am using Pure Nexus 7.1 now and can still see the 00000000 as a IMEI, if I restore my efs and get IMEI back showing correctly, no LTE/4g signal! My phone can only function as it should as long as the IMEI doesn't show correctly! I have tried just flashing base bands and other segments of any rom and still the problem persist! I have even tried restoring an EFS from another nexus 6 and still no help. It's not the sims because I've tried AT&T sims and Verizon sims from other phones and it does the same thing! I've tried flashing with a sims in the phone and without. Any ideas??? It's like somehow a correlating segment of a file is not being recognized when the correct IMEI is present, like some thing some where in the efs, IMEI, and radio are not taking to each other so to speak, unless it shows the zero's! Brain waves come on and help me out here!
TheWacoKid said:
Ok, Ladies and Gentleman I need some deep thought processing here for some help with a Motorola Nexus 6. In brief here is what the problem is, a while back when flashing Pure Nexus rom, I experienced a loss of my IMEI. I can restore my IMEI but if and when I do, I lose any 4g and LTE connectivity. The phone functions in 3g with data and phone etc... just slow as molasses but if I restore my IMEI to the one that doesn't show up my IMEI correctly I get back LTE/4g and all works fine also. I've tried going all the way back to the original firmware which was saved to computer and restoring it. Same thing, I have IMEI but no LTE/4g. restore bad efs and get LTE/4g back. I've tried going through all the factory firmware's and flashing by ADB and or TWRP and nothing firmware wise will allow me to restore the IMEI and have LTE/4g signal. If I restore the bad efs and get OOOOOOOO for IMEI when using the *#06# on any firmware version, I regain LTE/4g functioning! I am using Pure Nexus 7.1 now and can still see the 00000000 as a IMEI, if I restore my efs and get IMEI back showing correctly, no LTE/4g signal! My phone can only function as it should as long as the IMEI doesn't show correctly! I have tried just flashing base bands and other segments of any rom and still the problem persist! I have even tried restoring an EFS from another nexus 6 and still no help. It's not the sims because I've tried AT&T sims and Verizon sims from other phones and it does the same thing! I've tried flashing with a sims in the phone and without. Any ideas??? It's like somehow a correlating segment of a file is not being recognized when the correct IMEI is present, like some thing some where in the efs, IMEI, and radio are not taking to each other so to speak, unless it shows the zero's! Brain waves come on and help me out here!
Click to expand...
Click to collapse
Greetings and welcome to assist. Have you tried asking in the pure nexus thread to see if anyone else has had this issue ? I have seen it before when flashing aosp/cm based roms but the fix is usually different each time
Regards
Sawdoctor

Backup imei using dd or something similar

Hi guys,
I factory reset my s7 recently and when trying to root it again I lost my imei. Luckily I was able to restore using my old twrp backup which brought my imei back.
I restored the whole system, although I actually just wanted to use the imei partition.
So I guess I have two questions here, the first being: in theory, could I have just rooted the new factory reset device (with the imei missing) and restore the efs partition from twrp only? Would that work? Or, even more convenient, would there have been any way to write the efs partition directly to restore the imei (using dd or something similar?).
It would be cool if the latter version would work because in that case I wouldn't have had to restore my backup.
And another thing: is there a way to backup the imei only? Or can I restore an efs partitions made from my lineagOs system with twrp on any ROM (e.g. stock) and get the imei back?
Greetings deM
Can't tell for sure if you can just dd your way through, but I know for sure you can tamper with the imei without restoring or flashing the whole firmware, tho! using a paid tool/dongle, the z3x got many features and repairing/changing imei is one of them, if it can directly change the imei without flashing anything then you probably could do it too, I would also mention this process requires root and adb, but I don't have quite the idea about the commands or steps needed (especially for dual sim) as that tool I mentioned does the thing for me!
Salazar33 said:
Can't tell for sure if you can just dd your way through, but I know for sure you can tamper with the imei without restoring or flashing the whole firmware, tho! using a paid tool/dongle, the z3x got many features and repairing/changing imei is one of them, if it can directly change the imei without flashing anything then you probably could do it too, I would also mention this process requires root and adb, but I don't have quite the idea about the commands or steps needed (especially for dual sim) as that tool I mentioned does the thing for me!
Click to expand...
Click to collapse
Okay thanks for the input. Using this tool is of course legit, I'm just curious if it could be achieved only by using a shell. Because in theory we have access to the filesystem if we're rooted so I figured we might be able to just to this using dd or something.
Greetings deM
derelektrischemoench said:
Okay thanks for the input. Using this tool is of course legit, I'm just curious if it could be achieved only by using a shell. Because in theory we have access to the filesystem if we're rooted so I figured we might be able to just to this using dd or something.
Greetings deM
Click to expand...
Click to collapse
I noticed I didn't give you an answer for your question about restoring the EFS backup, and yes it works, you can even copy it from a phone to another, sometimes it works across different android versions too but that I didn't test myself.
In the shop I work in, we rarely get Samsung phones that have IMEI issues, but Mediatek and most cheap chinese phones, Yes, whenever there is an issue with IMEI or cellular network, I erase the existing NVRAM and flash a new one, and most of the time that solves it, for IMEI I use another Jtag called CM2 (chinese miracle 2) but it doesn't support the newer Mediatek chips with fully locked bootloaders, some clients won't go as far as unlocking the bootloader cause of the warranty and what not. Besides the CM2, rooting and using the engineering mode, you can push the new IMEI easily, with Samsung you can do that with root as well, but its way harder and doesn't work on new Android Versions!
Back to the Z3x and the S7, I've done some research, and from what I learned it accesses the EFS partition or something, with root ofcourse, it reads some specific sectors that contains the IMEI and network informations, then using zTool, which I don't know if its part of Z3x or some other software, to modify that information and basically allow to the network to be fully functional.

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