Develop Bugs

Is there Diag mode code for T-mobile M8?

How can i enable diagnostic mode on T-mobile Htc M8?
3424 doesn't work

jkjambo said:
How can i enable diagnostic mode on T-mobile Htc M8?
3424 doesn't work
Click to expand...
Click to collapse
if your in sense why not just use the phone diagnostics from sense? its *#*#4636#*#*

syaoran68 said:
if your in sense why not just use the phone diagnostics from sense? its *#*#4636#*#*
Click to expand...
Click to collapse
that's completely different thing
i need diag mode and that's only test mode

what are you trying to diagnose?

syaoran68 said:
what are you trying to diagnose?
Click to expand...
Click to collapse
why are you interested in this?
i need it for few reasons , like trying to unlock lte bands , to make a back up of qcn , ect...
so is there diag mode for t-mob m8 or not? or do i need some kernel with it?

jkjambo said:
why are you interested in this?
Click to expand...
Click to collapse
Because if we know what you're trying to do we can give better advice.
Unless what you're trying to do is technically against forum rules, of course

jkjambo said:
why are you interested in this?
i need it for few reasons , like trying to unlock lte bands , to make a back up of qcn , ect...
so is there diag mode for t-mob m8 or not? or do i need some kernel with it?
Click to expand...
Click to collapse
what was said above ^
but back to your question. Yes there is a diag mode available, but you need a bypass card in order to access it. this diag mode is normally meant for diagnosing faulty mainboards, and the such.
so basically yes there is a mode, but no your not going to be able to get access to it. cause the card itself is a unicorn, and there have been some home made cards but realistically if your trying to download / change the bands its nearly impossible. since the firmware's are so locked down.

EddyOS said:
Because if we know what you're trying to do we can give better advice.
Unless what you're trying to do is technically against forum rules, of course
Click to expand...
Click to collapse
what can you do with diag mode which is against rules? i'm not trying to change imei or something like that
syaoran68 said:
what was said above ^
but back to your question. Yes there is a diag mode available, but you need a bypass card in order to access it. this diag mode is normally meant for diagnosing faulty mainboards, and the such.
so basically yes there is a mode, but no your not going to be able to get access to it. cause the card itself is a unicorn, and there have been some home made cards but realistically if your trying to download / change the bands its nearly impossible. since the firmware's are so locked down.
Click to expand...
Click to collapse
it's avaliable on sprint m8 with this code ##3424# , so what's problem with t-mob m8?
i think there should be some adb commands at least, but i'm asking if there is some code for it , like it's on sprint version

It should be the same code for all devices, unless the carrier has disabled it

EddyOS said:
It should be the same code for all devices, unless the carrier has disabled it
Click to expand...
Click to collapse
not working on t-mobile m8 . as i know *#*#3424#*#* works on gsm m8 (international version) , but it doesn't work on t-mobile . i'm now on lollipop , but it wasn't working on kitkat too

here is answer . Thanks to marhinal88
On:
su
echo 1 > /sys/devices/virtual/android_usb/android0/f_diag/on
Off:
su
echo 0 > /sys/devices/virtual/android_usb/android0/f_diag/on

[Help] how to enable engineering mode?

how to enable engineering mode? I tried *#*#4636#*#* but nothing happened!
any solution?
Ps. I'm non-root

For me it's working so I guess you have a carrier version that maybe have this option not available. I have the Google version.

you can always borrow someones sprint sim fir a bit then ull have access to a lot of commands.. i was able to get data programming, debug menu, the 4636 etc etc on a vzw variant just by utting in a dif sim

hostmark said:
how to enable engineering mode? I tried *#*#4636#*#* but nothing happened!
any solution?
Ps. I'm non-root
Click to expand...
Click to collapse
Worked here Verizon pixel 3 xl

[GUIDE] Moto G7 Power/Supra [All Versions] Enable ALL LTE Bands (maybe?)

Note: I need some feedback to determine if this is *actually* working for people, since where I live, bands 2/4 are the main LTE bands for AT&T and T-Mobile and the International G7 Power (XT1955-2) supports those.
DISCLAIMER: I am not liable for any damage or legal liability caused by this guide or the improper application of it. As usual, do this at your own risk!
With that out of the way, lets do this:
You will need:
1. Your Moto G7 Power/Supra (any version). Not sure if you need to be rooted/bootloader unlocked or not. Mine is has already had both done. My guide to unlocking/rooting the G7 Power is here: https://forum.xda-developers.com/g7-power/how-to/versions-moto-g7-power-supra-magisk-t3923857
2. A usb cable to connect your g7 to a (windows) computer.
3. A windows computer.
4. Qualcomm QPST: (I used version 2.7.477) https://mirrors.lolinet.com/software/windows/Qualcomm/QPST/QPST.2.7.477.zip
5. Motorola USB Drivers: https://support.motorola.com/us/en/drivers
Step 1: Get QPST up and running
First download and install your Motorola USB drivers from earlier. Then download and install QPST. Boot your phone to the bootloader by rebooting and holding the volume down button or by turning off then holding power + volume down until the bootloader menu appears.
Using the volume up/down keys select "BP Tools" and then use the power key to boot the phone. Wait till its done then ensure USB debugging is turned off. If you dont know what that is, then it's probably off.
Go into device manager in windows by pressing windows key+r and typing devmgmt.msc. You'll see 3 devices under "other devices" without drivers (unless you got lucky and they automatically installed, mine didnt). We are intrested in the 3 that are named "moto g(7) power". We only need one of these, but its unclear what the correct one is, so repeat this process for all 3:
Right click and select "update driver"
Click "browse my computer for software"
Click "let me select from a list of availible drivers"
Scroll down to find "ports (com and lpt)"
Select "Motorola" as the manufacturer and "Motorola QC Diag Port" as the model
Ignore the "update driver warning" that comes up
Once you've got those installed, open QPST Configuration from the Start menu. It will show 3 devices, select the one that actually shows an esn. Then click "start clients" and then "Service programming"
Step 2: Unlocking the bands with QPST Service Programming
When QPST Service Programming opens, select your phone and hit OK. Then, click "read from phone" and wait a second for it to finish. Under the tab "UMTS System" you should see a bunch of checkboxes (most of them unchecked). At this point, you probably should click "Save to file" to backup what you're about to change.
You can select with the checkboxes specific bands you want to enable, but dont uncheck any that are already there. Alternatively you can do what I did and #yolo. Check "Any BC" to select them all. Dont mess with any of the other options but the "preferred bands" checkboxes because honestly I have no idea what that might do. When you're ready, click "Write to phone" and wait. I ended up getting an error that the "device stopped responding to read/write commands" and almost had a heart attack, but after closing and reopening QPST and clicking "read from phone" again, everything I had selected and wrote previously was still there.
Now, reboot your phone and give it a shot. You can confirm the changes stuck by booting back into BP tools mode through fastboot then opening QPST Configuration and the QPST Service Programming and clicking "read from phone" again.
Please let me know if this worked for you; if bands you previously could not get started working or if now LTE is working for you when it previously wasnt. You can check this by using the LTE Discovery app on the Play Store https://play.google.com/store/apps/details?id=net.simplyadvanced.ltediscovery&hl=en_US. As I stated earlier, bands 2 and 4 are the main LTE bands in my (rural) area so I cannot confirm this for myself. What I can confirm however that going through this process wont brick your device (unless you really screw up).
Thanks to samwathegreat for his guide here on getting the QC Diag drivers working/the phone showing up as a COM port which is required for this to work: https://forum.xda-developers.com/showpost.php?p=54338876&postcount=3
And thanks to bpear96 who made an older guide for older phones with an older QPST which I was able to graft into this guide for the G7 Power with the newer version of QPST: https://forum.xda-developers.com/moto-g/general/unlock-hspa-bands-moto-g-1700mhz-xt1032-t2878441
I'm still trying to get 5Ghz wifi working on the International model (XT1955-2) but am unsure if that's even a possibility. Any insight on that is welcome too .

Thanks for the great work, very hopeful that you can get 5Ghz wifi working. I've got the G7 power ordered, should be able to try out your guide in a few days, I'll let you know how it works.

Current status?
So its been a while whats the verdict is it possible? Also thanks for posting this guide.

magiricod said:
So its been a while whats the verdict is it possible? Also thanks for posting this guide.
Click to expand...
Click to collapse
Havent gotten any feedback regarding this yet, unfortunately.

Didn't work for me. I tried going old school by using QXDM/NV Browser and editing 06828 record, I think that was the record. It looked like it accepted the entry but the phone hung at boot and upon a second reboot the phone still didn't have the bands.
I also tried changing the device's information using fastboot oem hw utags but that seems to be a dead end. It seems there is an even lower system check before the bootloader/fastboot level. I think we may have to use edl and write the the modem. I just don't know enough about this low level stuff. Still researching though. I'm a little worried about pushing on because I can't afford replace the phone right now and not all the information on how to unbrick the phone is available yet.
I'm sure someone will figure out how to do it.

I tried this out but I haven't had any luck. It asks for a "Service Programming Code" when I try to "read from phone". If I bypass it, it will read, but when I try to write I get an error that it's not allowed.
Any ideas on where I could find the code?

So this is interesting, netmonster reports that I'm currently connected to lte band 66, although LTE Discovery says I'm on band 4. ??

diversenerd said:
netmonster reports that I'm currently connected to lte band 66, although LTE Discovery says I'm on band 4.
Click to expand...
Click to collapse
Has LTE Discovery been updated to show band 66? Last I checked it had not.

For me (XT1955-2) the screen is showing all bands already checked. The only checkbox disabled is the "Any BC".
I dont see 700Mhz but I see one checkbox already checked BC12 (I dont know if this is band 12). Please let me know whats happening...
---------- Post added at 02:33 AM ---------- Previous post was at 02:31 AM ----------

XT-1955-2: Bootloader unlocked and phone rooted.
Since I've had the phone it has been able to get LTE data pretty dang well on Verizon when set to LTE/CDMA ONLY, but can't make calls or SMS. I tried this method of checking bands but when I read from phone it has all bands checked already, except 'Any BC'. Just really hoping I can get this sorted out somehow.

So I have the metro version. It's unlocked, if I switch to visible I won't have access to the proper bands because of the metro rom?

Can someone please share a QCN file for a dual SIM variant?
I need it to compare to my single SIM one, cause I want to enable SIM2 but it has no IMEI.
halp pls?
also, when entering Service Programming Code, leaving it as 000000 doesn't throw any errors and reads well. Haven't tried writing though...

I tired it on my sim-unlocked Metro 1955-5, and did not give me any new LTE band options after i used the app provided..
btw, was the programming code supposed to stay at 00000?

Tolonus said:
XT-1955-2: Bootloader unlocked and phone rooted.
Since I've had the phone it has been able to get LTE data pretty dang well on Verizon when set to LTE/CDMA ONLY, but can't make calls or SMS. I tried this method of checking bands but when I read from phone it has all bands checked already, except 'Any BC'. Just really hoping I can get this sorted out somehow.
Click to expand...
Click to collapse
You get this sorted? I want to switch over to Verizon (tomorrow) but need confirmation that this phone will actually work with Verizon...
Software version: PPOS29.114-134-7
Stock Boot-loader.

illtww said:
You get this sorted? I want to switch over to Verizon (tomorrow) but need confirmation that this phone will actually work with Verizon...
Software version: PPOS29.114-134-7
Stock Boot-loader.
Click to expand...
Click to collapse
Well sorry to say it just isn't going to work with Verizon. This being double confirmed.

Followed steps, only thing not checked was Any BC, checked it, did the write and reboot and its still checked.
Does that mean its working?
Whats Any BC?
im on (XT1955-2)

Tolonus said:
Well sorry to say it just isn't going to work with Verizon. This being double confirmed.
Click to expand...
Click to collapse
It will work on any carrier the Sim has to be unlocked then u can use it any ware

diversenerd said:
Please let me know if this worked for you; if bands you previously could not get started working or if now LTE is working for you when it previously wasnt. You can check this by using the LTE Discovery app on the Play Store As I stated earlier, bands 2 and 4 are the main LTE bands in my (rural) area so I cannot confirm this for myself. What I can confirm however that going through this process wont brick your device (unless you really screw up).
.
Click to expand...
Click to collapse
So I have the -2 dual sim version, when I read from the phone i only had maybe 5 boxes checked off So I checked all boxes and wrote file to phone. all went well. rebooted and checked again and yes all were now active.
BUT I still do not pick up band 12. in my remote area I have band 2 and 12. side by side with my wifes LG she switches between band 2 and 12. and my moto g7 stays on band 2 then drops and has no service.
I still have no wifi calling or wifi texting with the phone. ready to throw it in the trash. any help would be welcome.

"phone not allowed for voice" error. Any help?

Hello everyone
I have an LG v30+ running stock android 9 with the global v31a rom.
Today I moved to a new carrier, and after installing new sim, the cellular internet works just fine, but voice calls and sms are not working.
I get the "phone not allowed for voice" message and on the taskbar shown on a "MM" icon.
At first I also received an error windows I attached here.
Moving the new sim to another newer xiaomi phone - everything works fine including calls and sms.
Customer service couldn't fix them from their said claiming it's an issue with phone configurations.
Any idea on how to fix this?
Thanks

I just tested another company's sim card and everything works fine.
So it must be some support from the new carrier
Any idea what can be done before I chose another carrier?

What is the model number (Settings -> General -> About phone -> Hardware info)?
Please share a screendump of your Network status screen (Settings -> General -> About phone -> Network). You can blank out the IP address.
Also, please share screendump of the Testing menu Phone information screen (dial *#*#4636#*#* -> Phone information). Scroll it up 3 lines lines so you don't share IMEI, Phone number, IMSI, but so that we can see all the Provisioned lines.
First thing I would try is a Network settings reset (Settings -> General -> Restart & reset -> Network settings reset) then restart the phone.
It is possible that your carrier only provides voice over VoLTE (and SMS over IMS, which is part of the same feature set). That only works if the phone knows the correct settings for your carrier. That would explain why it works with the newer Xiaomi phone. You can check if you have VoLTE settings in the menu (Settings -> Network menu -> Call). Even if the phone does NOT know your carrier, you may be able to configure it through the Hidden menu (depending on your model number). But it is VERY complicated, and you need detailed information from the carrier about the settings to enter.
Or it could be something else entirely.
On a different note, this thread definitely should have been in the Questions section, not in the Guides section.

KamaL said:
Hello everyone
I have an LG v30+ running stock android 9 with the global v31a rom.
Click to expand...
Click to collapse
Not sure why you are calling 31a "global". It's merely the European H930 31a Pie. I've seen a couple of other people use that term and not sure why... It's not "global" in any way than any other KDZ. (EDIT: I see your screenshot where it says global, which is very strange. Is that some setting? That's just weird.)
Unless you actually have an H930 phone, using the H930 KDZ will not give you the H930 bands or anything. You are still using the LTE/HSPA bands that are on your variant. Some people use H930 firmware on H930D/H930DS for different language options and vice versa. So, "global" is quite an exaggeration. Canada H933 has more LTE bands than any of the V30 variants, so it's really the "global" if any are. (But you can't convert to Canada H933 unless you have a compatible North American variant.)
What variant do you have and what country do you live in?

Ahh, so a European H930. Which country are you in, and who is the carrier?

KamaL said:
I just tested another company's sim card and everything works fine.
So it must be some support from the new carrier
Any idea what can be done before I chose another carrier?
Click to expand...
Click to collapse
I don't know where you live and what variant you actually have, but you are using EU H930 31a KDZ.
For instance, if you are in India and using Jio carrier, you need India H930DS KDZ as Jio is VoLTE only. But H930 31a doesn't have Jio's VoLTE settings... Using "another carrier" which allows legacy HSPA during phone calles would then be why it works on the other carrier but not Jio. To fix that you would need to flash India region H930DS firmware.
I am not saying you live in India or using Jio -- you didn't give us any information about that. I am just giving a real life example of why your phone would work on one carrier but not another.
Also, some carriers make you register your phone. If you just stick the same SIM card in you had from previous phone, it sees it's a different phone and will throw up an error message like that until you call them or go into store and tell them what "new" phone you are using. The "other carrier" may not be such a control freak.
---------- Post added at 10:37 AM ---------- Previous post was at 10:28 AM ----------
TheDannemand said:
Ahh, so a European H930. Which country are you in, and who is the carrier?
Click to expand...
Click to collapse
Since he says he has V30+, I know he doesn't have native H930 phone. There are no H930 V30+. The V30+ are H930G and H930DS and neither on them have firmware numbered "31a".
---------- Post added at 10:44 AM ---------- Previous post was at 10:37 AM ----------
KamaL said:
Hello everyone
I have an LG v30+ running stock android 9 with the global v31a rom.
Today I moved to a new carrier, and after installing new sim, the cellular internet works just fine, but voice calls and sms are not working.
I get the "phone not allowed for voice" message and on the taskbar shown on a "MM" icon.
At first I also received an error windows I attached here.
Moving the new sim to another newer xiaomi phone - everything works fine including calls and sms.
Customer service couldn't fix them from their said claiming it's an issue with phone configurations.
Any idea on how to fix this?
Thanks
Click to expand...
Click to collapse
I see posts from you back in November and you have been on 31a for awhile...
https://forum.xda-developers.com/showpost.php?p=81065243&postcount=852
So, any issues have to be with this new carrier as you have had phone calls on 31a for most of a year now.

Sorry, double post

Thanks everyone for the replies.
@TheDannemand
Some more information about my device:
Country: Israel
Carrier: We4G
Hardware version: LH-H930G.
Looking up using my IMEI number on lg-roms website gives this model: LG V30 Plus TD-LTE
I shared the network menu testing menu you mentioned.
I DO NOT see any VOLTE setting in the Call menu.
I already tried network settings reset.
@ChazzMatt
I have the H930G version. Actually I always follow your guides in that thread to upgrade the version, and I've been on this stock firmware for a year. So it must be something related to the carrier settings I think.
I actually didn't use my country's specific KDZ file as it was released a bit late. I used the european version if I remember well.
Should I flash the local one? According to lg-firmwares and lg-roms website it's this one:
Code:
https://lg-firmwares.com/downloads-file/21127/H930G30a_00_OPEN_IL_OP_0903
Will it have an impact on call services and bands?
Any chance it is really a carrier using VoLTE for calls? I tried asking all kind of questions but didn't get any smart answer from the tech support team.
Also, what do you mean by registering the phone? I never heard about this.
Thanks again!
View attachment 5082915View attachment 5082917View attachment 5082919

For some reason I cannot see your attachments. What I wanted to see was (1) whether you have an LTE connection and (2) whether the phone sees VoLTE as provisioned. In truth, I only need the Phone info screen (from the Testing menu) to see that.
I think it is quite plausible that your carrier requires VoLTE to make calls and that your ROM doesn't support it because it doesn't know your carrier. A ROM for your region probably DOES know your carrier (if they are well established). But it's also possible that it doesn't (if they're newer or changed their VoLTE parameters in recent years).
This was my first thought when I read your post and saw that you were on 4G (which should be LTE, although in USA carrier marketing departments have diluted the term to also cover old 3.5G). And I see that it is ChazzMatt's thought too, with the example from Jio India.
I googled We4G to get a clue if they're VoLTE only, but all the links were in Hebrew
Carriers who don't require VoLTE drop the connection to 3G in order to make calls. This works on every phone that supports LTE because it doesn't require knowledge about your carrier.
However VoLTE relies entirely on VoIP and requires an elaborate login to carrier servers, with security and handshaking to prevent illicit use of their network. And the parameters for that are carrier specific. Each phone has a so-called "buffet" of carrier configs known to that ROM. That's why it matters to use a ROM that knows your carrier.

Thanks for the detailed reply.
I think I'll try the local ROM I mentioned. I just want to be sure it doesn't make a clean wipe if I flash Kdz with LG UP. is that so?
I'm uploading the attachments once again.

Tapatalk is messing with attachments. Here's the last one

KamaL said:
Thanks for the detailed reply.
I think I'll try the local ROM I mentioned. I just want to be sure it doesn't make a clean wipe if I flash Kdz with LG UP. is that so?
I'm uploading the attachments once again. View attachment 5082947View attachment 5082949
Click to expand...
Click to collapse
Thank you. I see your attachments now.
So you do indeed have LTE connection for your mobile data. But the phone doesn't even pick up VoLTE provisioning -- which is the first and most basic step in supporting VoLTE.
I would definitely try the regional ROM, but you should flash with Refurbish or Partition DL -- which means losing data. Sorry.
In fact, since you're doing a Frankenstein, I would flash back to Nougat first using Partition DL (to update the partition table), perform a Master Reset (it may bootloop until you do), then flash up to Pie. Wait for @ChazzMatt to confirm those steps.
Good luck to you

TheDannemand said:
Thank you. I see your attachments now.
So you do indeed have LTE connection for your mobile data. But the phone doesn't even pick up voLTE provisioning.
I would definitely try the regional ROM, but you should flash with Refurbish or Partition DL -- which means losing data.
In fact, since you're doing a Frankenstein, I would flash back to Nougat first using Partition DL (to update the partition table), perform a Master Reset, then flash up to Pie. Wait for Chazz to confirm those steps.
Good luck to you
Click to expand...
Click to collapse
I really hope I can flash it without losing data. I prefer not to back up all data.
That's what I also did in the previous rom upgrades.
Would that be possible?

KamaL said:
I really hope I can flash it without losing data. I prefer not to back up all data.
That's what I also did in the previous rom upgrades.
Would that be possible?
Click to expand...
Click to collapse
I don't see any way to do this safely without losing data. Sorry.
You could skip that carrier and go with one that doesn't require VoLTE (i.e. one which supports the old dropping to 3G for calls). But you won't have the benefits of VoLTE and WiFi Calling. And you may be in the same situation later if that carrier decides to close down their 3G network and go VoLTE only.

KamaL said:
Tapatalk is messing with attachments. Here's the last oneView attachment 5082951
Click to expand...
Click to collapse
Try enabling 'VoLTE Provisioned' on that screen then restarting your phone.
Is there an 'Advanced Calling' menu in Settings?

Two things that might help:
1) Before taking the plunge, put the SIM in your Xiaomi phone and see if you can make a call WITHOUT using VoLTE: One way is if Settings menus allow disabling VoLTE. If no Settings menus, try the same Testing info - Phone info screen and see if VoLTE is provisioned there. I assume it is. But if VoLTE is ALSO not provisioned on the Xiaomi, that means the problem isn't lack of VoLTE on the V30.
2) Just backup the phone using LG Backup, either through Settings -> General menu -> Backup (then transfer file to PC or flash drive) or using LG Bridge. It backs up all app data and most phone settings (though not all). And I was able to use it across different ROM versions and even different ROMs (between H932 and US998).

jptV30 said:
Try enabling 'VoLTE Provisioned' on that screen then restarting your phone.
Is there an 'Advanced Calling' menu in Settings?
Click to expand...
Click to collapse
I can't turn it on unfortunately.
There's a call--> additional settings - - > other settings menu
But I get this error message when I try it, and then I lose LTE connection too.

jptV30 said:
Try enabling 'VoLTE Provisioned' on that screen then restarting your phone.
Click to expand...
Click to collapse
That one is info only, not a toggle -- even though it looks like it.
KamaL said:
There's a call--> additional settings - - > other settings menu
But I get this error message when I try it, and then I lose LTE connection too. View attachment 5082979
Click to expand...
Click to collapse
Yeah, as long as the phone doesn't see it as provisioned, we can forgot about menus and settings.

TheDannemand said:
Two things that might help:
1) Before taking the plunge, put the SIM in your Xiaomi phone and see if you can make a call WITHOUT using VoLTE: One way is if Settings menus allow disabling VoLTE. If no Settings menus, try the same Testing info - Phone info screen and see if VoLTE is provisioned there. I assume it is. But if VoLTE is ALSO not provisioned on the Xiaomi, that means the problem isn't lack of VoLTE on the V30.
2) Just backup the phone using LG Backup, either through Settings -> General menu -> Backup (then transfer file to PC or flash drive) or using LG Bridge. It backs up all app data and most phone settings (though not all). And I was able to use it across different ROM versions and even different ROMs (between H932 and US998).
Click to expand...
Click to collapse
I didn't find settings to turn off VoLTE.
Here are the settings on the xiaomi. It is NOT provisioned apparently.... View attachment 5082983

KamaL said:
I didn't find settings to turn off VoLTE.
Here are the settings on the xiaomi. It is NOT provisioned apparently....
Click to expand...
Click to collapse
The screenshot doesn't include the VoLTE line. But if VoLTE is ALSO not provisioned on the Xiaomi that means the problem if elsewhere, not lack of VoLTE on the V30. So hold off on that Frankenstein for a bit.
I have a client meeting coming up, probably won't have more time today. But this is good news, kind of

Question How to get to the carrier_policy.xml file in Oxygen OS 12?

So, Oxygen OS 11 didn't support 5G on my carrier out of the box. However, I managed to get it to work by replacing the carrier_policy.xml file with this tutorial:
OnePlus Community
Introducing our new OnePlus Community experience, with a completely revamped structure, built from the ground-up.
forums.oneplus.com
It got wiped with every system update, but it's never been hard to reenable. However, with Oxygen OS 12, the procedure doesn't work at all because the Engineering Mode APK refuses to install. So, I'm stuck on 4G. Is there any other way to get to said file and replace it? Preferably without rooting the phone. Thanks in advance.

For some people (me included) 5G is working, but on 2nd SIM slot only.

MaUop3 said:
For some people (me included) 5G is working, but on 2nd SIM slot only.
Click to expand...
Click to collapse
Mine's not working at all. Two different carriers, the option shows up in the menu, but enabling it does nothing. It's exactly what happened in Oxygen OS 11 before I replaced the carrier policy file, hence why I'm specifically asking for a way to reach it in Oxygen OS 12.

Shady Guy Jose said:
Mine's not working at all. Two different carriers, the option shows up in the menu, but enabling it does nothing. It's exactly what happened in Oxygen OS 11 before I replaced the carrier policy file, hence why I'm specifically asking for a way to reach it in Oxygen OS 12.
Click to expand...
Click to collapse
You enabled nr by doing *#*#4636#*#* right?

Zeus0fyork said:
You enabled nr by doing *#*#4636#*#* right?
Click to expand...
Click to collapse
*#*#4636#*#* no longer works in OOS12

MaUop3 said:
*#*#4636#*#* no longer works in OOS12
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Indeed, but I do have 5G enabled in settings, the option does show up. It simply doesn't detect my network, something that, in OOS11, could be fixed by replacing the carrier policy file.

same thing with me
I enabled 5g option from ssettings but still shows 4G+ only and no 5G
and *#*#4636#*#* not working anymore
Is there a way to replace carrier_policy.xml ???