i have lost my 2g/3g network is slot 1

[salmanvts]

My first sim is only support 4g network, and second sim working perfectly with all network.
My device Lenovo p2a42
I think I lost GSM/UMTS band
I accidently click the United States band on *#*#4636#*#*
I a currently on marshmallow
I do all the factory reset setting but the problem is still,

 

[fburgos]

I've own several devices and there's always a guy messing with their bands and that service menu and lost something I wonder why?

Good luck

Sent from my ONE A2005 using Tapatalk

 

[solazz]

My first sim is only support 4g network, and second sim working perfectly with all network.
My device Lenovo p2a42
I think I lost GSM/UMTS band
I accidently click the United States band on *#*#4636#*#*
I a currently on marshmallow
I do all the factory reset setting but the problem is still,

If your bootloader is still locked, have u tried flashing the fastboot image? There are instructions provided in some of the thread in the P2 section so u can try that. Note though that this is for the global version of P2... So the P2 that is linked to the service provider like Three in the UK might not be compatible (Volte might not work for example)

 

[salmanvts]

My problem is solved [SOLVED]

My device problem is solved
I update to nought using computer via adb commands
Note:-ota update canot solved my problem, i manully download the stock rom and flash through adb


****Thanks for All*********

 

[botson71]

My device problem is solved
I update to nought using computer via adb commands
Note:-ota update canot solved my problem, i manully download the stock rom and flash through adb

I have exactly the same problem with the 2G/3G on slot 1.

Could you write here in a little more detail the steps you followed in order to solve the problem?

For example, what stock rom, downloaded from where, what procedure through adb etc.

Thanks in advance

 

[j.jeedz]

For me. Sim1 lost 2G but 3/4G is ok.

 

[salmanvts]

I have exactly the same problem with the 2G/3G on slot 1.

Could you write here in a little more detail the steps you followed in order to solve the problem?

For example, what stock rom, downloaded from where, what procedure through adb etc.

Thanks in advance

I will tell you the solution
i am in marshmallow and i download the stock Rom with a web site
http://www.mediafire.com/file/no35yqbt5ssj5b2/Lenovo_P2a42_S233_20170404.zip

1. Download the Rom file to PC And Extract it
2. install your USB driver to PC (it automatically install your when your device connected)
3.enable USB debugging under developer option or USB settings
4.When USB debugging is on your phone will come a popup and allow the prompt
5.switch off your device and press volume- and Power Button and it will enter to fast boot mode
6. open the extracted folder in your PC and there is firmware folder open and there is a file flashall click and run the file
7. it will automatically run all the command
8. after completing your device restart automatically and update was complete

After that my Problem is Solved

 

[botson71]

Thank you for the detailed steps.

I'm not in Marshmallow though but in Nougat S233.

I hope that re-flashing the stock S233.zip to the already present S233 with this method will work

 

[j.jeedz]

I will tell you the solution
i am in marshmallow and i download the stock Rom with a web site
http://www.mediafire.com/file/no35yqbt5ssj5b2/Lenovo_P2a42_S233_20170404.zip

1. Download the Rom file to PC And Extract it
2. install your USB driver to PC (it automatically install your when your device connected)
3.enable USB debugging under developer option or USB settings
4.When USB debugging is on your phone will come a popup and allow the prompt
5.switch off your device and press volume- and Power Button and it will enter to fast boot mode
6. open the extracted folder in your PC and there is firmware folder open and there is a file flashall click and run the file
7. it will automatically run all the command
8. after completing your device restart automatically and update was complete

After that my Problem is Solved

It's work. thank you very much.

 

[salmanvts]

There is another way to solve this problem

[emoji732] some user reported this methode in unlocked boot loader device may be cause lost imei, make a twrp backup completely and proceed, other wise try the first methode [emoji732]



Resetting the modem information through fastboot
1. Enter Fastboot Mode
2. Type the Command

fastboot erase modemst1
fastboot erase modemst2
fastboot reboot

Dont worry , the erase command , it will reset the modem and reolve network issues (accedently change band issue)

:good:

 

[pranavateja99]

There is another way to solve this problem
Resetting the modem information through fastboot
1. Enter Fastboot Mode
2. Type the Command

fastboot erase modemst1
fastboot erase modemst2
fastboot reboot

Dont worry , the erase command , it will reset the modem and reolve network issues (accedently change band issue)

:good:

This all for locked bootloader.....I too face this issue and my bootloader is unlocked.

As soon as I hit erase modemst1,st2 on unlocked bootloader device...I will loose signal and can be everything related to IMEI.

Sad thing with unlocked bootloader P2 is fastboot flashing don't flash modem. There me be some fix process for unlocked bootloader.

For bootloader locked anything people do is a solution.
Also its not necessary to delete modemst1,st2.
Just reflashing stock will fix.

 

[salmanvts]

Chek the first methode it will work sure

 

[pranavateja99]

Chek the first methode it will work sure

4g only sim1 signal Problem is bcz *#*#4636#*#* mode selected to United states....Lenovo stock has U.S option only. If someone select united states then sim1 is stuck to 4g mode.


*#*#4636#*#*
Lenovo Stock ROM has only mode option: United states.
Custom ROM has 2 modes: Automatic and united states as options. Selecting Automatic fix sim1 4g only issue.

Solution for different users:

---------- Post added at 12:31 PM ---------- Previous post was at 12:16 PM ----------

I will tell you the solution
i am in marshmallow and i download the stock Rom with a web site
http://www.mediafire.com/file/no35yqbt5ssj5b2/Lenovo_P2a42_S233_20170404.zip

1. Download the Rom file to PC And Extract it
2. install your USB driver to PC (it automatically install your when your device connected)
3.enable USB debugging under developer option or USB settings
4.When USB debugging is on your phone will come a popup and allow the prompt
5.switch off your device and press volume- and Power Button and it will enter to fast boot mode
6. open the extracted folder in your PC and there is firmware folder open and there is a file flashall click and run the file
7. it will automatically run all the command
8. after completing your device restart automatically and update was complete

After that my Problem is Solved

For bootloader locked you can do anything to fix. Flashing anything can fix it. Bcz fastboot flash can rework modem. Everything is a fix.

For bootloader unlocked devices fastboot don't flash modem files. Only way is to install custom ROM...Dail *#*4636#*#* and selecting Automatic and restarting the device fix sim1 4g only error.

*#*#4636#*#* U.S settings problem stays even user updates from S062 to S244 via OTA. Like IMEI stays this setting to stays.

Never hit erase after unlocking bootloader in future for any signal or modem reasons. This lenovo p2 can screw your Android experience

---------- Post added at 12:39 PM ---------- Previous post was at 12:31 PM ----------

Chek the first methode it will work sure

Never suggest without knowing everything completely. You know and seen one side of a coin. P2 will show you real stars if you ever tried to erase or delete modem stuff after unlocking bootloader. You don't kill someone's phone with unlocked bootloader....stay away from stuff you have no idea.

 

[salmanvts]

4g only sim1 signal Problem is bcz *#*#4636#*#* mode selected to United states....Lenovo stock has U.S option only. If someone select united states then sim1 is stuck to 4g mode.


*#*#4636#*#*
Lenovo Stock ROM has only mode option: United states.
Custom ROM has 2 modes: Automatic and united states as options. Selecting Automatic fix sim1 4g only issue.

Solution for different users:

---------- Post added at 12:31 PM ---------- Previous post was at 12:16 PM ----------



For bootloader locked you can do anything to fix. Flashing anything can fix it. Bcz fastboot flash can rework modem. Everything is a fix.

For bootloader unlocked devices fastboot don't flash modem files. Only way is to install custom ROM...Dail *#*4636#*#* and selecting Automatic and restarting the device fix sim1 4g only error.

*#*#4636#*#* U.S settings problem stays even user updates from S062 to S244 via OTA. Like IMEI stays this setting to stays.

Never hit erase after unlocking bootloader in future for any signal or modem reasons. This lenovo p2 can screw your Android experience

---------- Post added at 12:39 PM ---------- Previous post was at 12:31 PM ----------


Never suggest without knowing everything completely. You know and seen one side of a coin. P2 will show you real stars if you ever tried to erase or delete modem stuff after unlocking bootloader. You don't kill someone's phone with unlocked bootloader....stay away from stuff you have no idea.

Check the post I will already mentioned that bootloader unlocker devices are lost their imei, dont do any thing without a nandroid backup

And my first method is used to all the update the device and not cause any problem


Sent from my Lenovo P2a42 using Tapatalk

 

[pranavateja99]

Check the post I will already mentioned that bootloader unlocker devices are lost their imei, dont do any thing without a nandroid backup

And my first method is used to all the update the device and not cause any problem

Even nandroid backup don't help restoring signal and ear piece sound errors....this is p2 and you can't flash fastboot modem image and you can't even relock bootloader. this is not normal like rest of the phones you used. Only QCN backup with QPST can backup IMEI+ rest and restore without issues. Only QPST Qfil flashable image bring back bootloader unlocked and messed up P2. This QPST image has to come from Lenovo, or someone has to make it with some internal sources and tools. So P2 is not normal stuff you used till now..it's locked Lenovo great sh*t....I don't know what they gain with bootloader warranty terms. But it's a hard messup ship for developers on XDA.

 

[eried1]

I bought a used P2 and I get no signal when inserting my SIM. I restored a nandroid backup from another P2 (Boot, Data and System). Could that be the reason it's not working? In that case, I wouldn't understand why it would have such an impact.

 

[sergsinger]

Could that be the reason it's not working?

It is the main reason!

 

[eried1]

It is the main reason!

I had no idea that could happen when you only flashed boot.img, data and system (same OS version). Used to do it all the time when I owned a couple of LG G2s.

 

[parky169]

i did the erase modem and now have no signal at all now what do i do

 

[Balukaust72]

Even nandroid backup don't help restoring signal and ear piece sound errors....this is p2 and you can't flash fastboot modem image and you can't even relock bootloader. this is not normal like rest of the phones you used. Only QCN backup with QPST can backup IMEI+ rest and restore without issues. Only QPST Qfil flashable image bring back bootloader unlocked and messed up P2. This QPST image has to come from Lenovo, or someone has to make it with some internal sources and tools. So P2 is not normal stuff you used till now..it's locked Lenovo great sh*t....I don't know what they gain with bootloader warranty terms. But it's a hard messup ship for developers on XDA.

Hi pranavateja99,
i have a p2 and i dont a have signal, no service at all on both sim.
I tried many variant of solutions, and unfortunately still wrong.
Ive tried stock rom 6.0 and ota update , nothing.
After few mounts i have no idea what can i do. i could fix my former phones but this one is beats me...
I just want to ask if you can give me some advice how can i fix it if is possible at all....
custom rom lineage, nothing, delete modem, nothing. bootloader is unlocked and this point when i found your comment here.
regards Steve