topic Re: WARNING: Never Change Radio Band in Z Series

WARNING: Never Change Radio Band

TomKay — Tue, 16 Dec 2014 15:54:37 GMT

Perhaps this warning will save some users a lot of painful hours.

I just spend hours on end to get my phone back to normal because I had accidentally changed the radio band to "USA band" and there is no easy way to revert that.

Now one could argue I should not have accessed the testing menu in the first place, but the phone was getting a bit warm at the back and I wanted to check the temperature. I had forgotten where to look exactly so I looked around a bit and once I saw "radio band" I was curious which options would appear.

After selecting "radio band" only one choice popped up "USA band". Now had I not been still a bit stressed from a phone call and been a bit too tired, I might have figured out that I should have pressed anywhere outside the button, but, PLEASE, if there is only one option, how can it be a wrong one way street?

I had to backup the phone, factory reset it, restore the data and recreate all my settings and app icon arrangements. I couldn't choose the firmware I had been happy with but had to jump to 157 (with unknown consequences). I had issues with some applications which updated to newer versions without my approval so some saved game states won't load back anymore. Luckily, I could revert to an older version of Chrome which does not ignore bookmarks placed on the homescreen (why do bugs like that not get fixed? But I digress). I had to find a workaround for my phone being unable to pair with my PC anymore and luckily I found an answer on this forum.

Fortunately, I anticipated that my app icons won't reappear at their previous positions despite the fact that I tried the phone back up and a PC companion backup, and had taken pictures of my home screens before the factory reset.

I literally spent six hours just because my finger was a split second quicker than my brain when I was faced with a "one option"-choice while searching for the temperature reading.

I appreciate that a testing or a service menu must be approached with caution, but even experienced technicians make mistakes from time to time. AFAIC, there should be no way (I'm sparing you the expletives here) to essentially render your phone useless with one touch of a button

without an explicit alternative being offered (implying the one choice must be OK), and
without being asked for confirmation (for such a significant change), and
without an option to go back and reconfigure the correct band (why make it a one way street?).

It leaves me puzzled how anyone could set up a combination of all these three factors, be it in a service menu or not.

Re: WARNING: Never Change Radio Band

Uliwooly — Tue, 16 Dec 2014 17:26:13 GMT

That's quite interesting, how did you "accidentally" change the radio band ? did you flashed a different frmware or baseband or custom ROM, I wasn't aware that we could change the "radio band" that's new to me

Re: WARNING: Never Change Radio Band

TomKay — Wed, 17 Dec 2014 22:58:25 GMT

@uliwooly wrote:
That's quite interesting, how did you "accidentally" change the radio band ?

I went into the (EDIT) testing menu (dialer -> *#*#4636#*#*) because I was looking for the battery temperature. When you first choose "Phone Information" and select the three-dot menu at the top right, you'll see "Select radio band".

If you select it, you'll get the one "select USA band" button. Don't press it unless you live in the USA or want to have a lot of fun to get your phone working again.

@uliwooly wrote:
did you flashed a different frmware or baseband or custom ROM, I wasn't aware that we could change the "radio band" that's new to me

That's the shocking part. I run a stock rom. My bootloader is locked. My phone is not rooted. I only went into the service menu and was slightly too tired to avoid pressing a one option button.

I'm now still "having fun" with the new version of Google Play Service (or Google Search, I'm not sure yet) periodically activating the GPS even though I explicitly turned off all location reporting and location history.

I'm so not in love with Google right now as they keep draining my battery against my explicit refusal of consent to let them.

EDIT: It may be the "Location-based Wi-Fi" option in 14.4.A.0.157 that activates the GPS (even though according to the description it should only use the network based location information). I'm not a 100% sure yet who the culprit is. I know for sure that my previous 14.4.A.0.108 firmware never activated GPS unless I explicitly used a respective application.

Re: WARNING: Never Change Radio Band

Uliwooly — Thu, 18 Dec 2014 00:47:57 GMT

You can't change it, it does NOT make sense.

Re: WARNING: Never Change Radio Band

TomKay — Thu, 18 Dec 2014 07:19:02 GMT

@uliwooly wrote:
You can't change it, it does NOT make sense.

Sorry, I made a mistake earlier when I referred to the "service menu" because I meant to write "testing menu".

Use your dialer to enter *#*#4636#*#*) and then choose "Phone Information". You'll see a three-dot menu at the top right of which the first item is "Select radio band".

I suggest to not even go there, but if you want to see which bands you can select from, make sure you do not press the soft button that will appear if it is only one (wrong) option.

Re: WARNING: Never Change Radio Band

ratacit — Fri, 19 Dec 2014 01:51:58 GMT

Checked it on my Hong Kong version z1c and USA is the only choice

Re: WARNING: Never Change Radio Band

Anandps — Fri, 20 Mar 2015 16:54:43 GMT

can somone please provide me the steps to revert this issue, is i ned to factory reset then how to do that as i have reset my phone with the reset option in setting menu -> backup and reset, but the problem is still same, no network signals..... plz plz plz reply me asap

Re: WARNING: Never Change Radio Band

Feek — Wed, 01 Apr 2015 15:30:13 GMT

hi, if you're an android user, install mtk engineering mode app from google play. Open app>MTK settings>telephony section>find BandMode> select sim you are usng>check all boxes that are available in GSM and UMTS and thats it. Desclaimer, dont play around with other settings if you dont know their function. unstall it after using to keep you from tempting to play with it. please reply if it fixed your problem ty

Re: WARNING: Never Change Radio Band

puneet0009 — Tue, 23 Jun 2015 06:55:04 GMT

I am in the same condition. My Xperia z and z2 are not reading SIM. Please help, its very serious.

Re: WARNING: Never Change Radio Band

1bit — Wed, 24 Jun 2015 13:27:55 GMT

Have same problem as @TomKay

selected by mistake in Testing screen - Phone information - Select radio band - Set GSM/UMTS band - USA Band (I was curious if there are any other menu)

My phone is locked to LTE only network (no 3 and 2G), here in the UK, no VoLTE and with three.co.uk no decent LTE coverage

Installed MTK Engineering Mode Start on my Z3 Dual 5.0.2 Build number 23.1.1.E.0.1 (Import from HKG) and I am unable to enter MTK Settings in the app (Cannot find EnginneerMode App msg. appears at the bottom of the screen).

Anyone has any idea hot to fix it?

Re: WARNING: Never Change Radio Band

TomKay — Wed, 24 Jun 2015 14:23:03 GMT

Just to repeat that there is a solution, i.e., a way to recover from selecting the wrong radio band.

One has to create a backup of the phone, factory reset it, and then restore the backup.

Obviously the factory reset on its own works as well, but most would probably want the "fix" to have the least possible impact, hence the recommendation to make a backup first.

Note that a backup does not cover everything, so for instance you may want to record how you placed your app icons, or other configuration details that may not will be restored.

Re: WARNING: Never Change Radio Band

9elsen — Sat, 25 Jul 2015 15:07:49 GMT

Well I admit I did it. And used 4 hours before I found this description. Thanks TomKay.
To Feel. By 'android user' do you mean rooted on th phone?
My phone is not rooted so I guess I have to take the long road.
My reason for being in the interesting menus was That I find that my phone does not function as well with 🍭 on.
Is there any new fix for this btw?

Re: WARNING: Never Change Radio Band

9elsen — Sat, 25 Jul 2015 15:09:01 GMT

Sorry not Feel but Feek

Re: WARNING: Never Change Radio Band

Tasfique — Tue, 08 Sep 2015 18:35:22 GMT

The easiest solution is flashing the baseband with flashtool... worked for me, no data were effected

Re: WARNING: Never Change Radio Band

maxiimum — Wed, 16 Dec 2015 10:21:19 GMT

Thank you for mentioning this problem
I'm from Tunisia and yesterday I had the same problem, I pressed the button accidently and you can't change it after that

Now, in the current time, I'm going to copy the files from the internal memory then restore the phone (factory reset).
I hope I will a signal back ...

Re: WARNING: Never Change Radio Band

Akash_tkr — Thu, 21 Apr 2016 15:33:17 GMT

It works I was also suffering from that issue...
i did same procedures and signal came back but lost my SIM which was in slot one....
SIM in slot 1 got blocked....
Sim got blocked only on my mobile phone...
but was operating well in other mobile phones...
bought duplicate SIM and then now its working good.....

Re: WARNING: Never Change Radio Band

oalgvi17 — Wed, 27 Apr 2016 18:44:10 GMT

hi friends,

I have the same problem.

I have installed MTK Engineering Mode but not working with my phone.

unfortunatelly, my phone is not a MTK android.

it is XIAOMI MI5 dual sim, but not rooted.

a very new phone on which both slots work LTE/4G/3G simultaneously.

(no other dual sim works in the same way.

all other dual sims work LTE/4G/3G on a slot, and 2G only on the another slot.)

I did factory reset 10 times, but not working.

any idea, please?

do you know what to erase to not restart again with USA BAND after factory reset?

will I flash it?

thank you.

Re: WARNING: Never Change Radio Band

cmantas — Mon, 02 May 2016 00:00:54 GMT

Hey, oalgvi17, if you only have one sim, try putting it in the other slot.
It worked for me until unfortunatelly (or more like stupidly) I repeated the mistake for the second sim too.
Anyone have an idea on how to revert it?
I cannot even get an sms for unlocking the bootloader so as to try flashing anything

Re: WARNING: Never Change Radio Band

oalgvi17 — Mon, 02 May 2016 11:15:49 GMT

unfortunatelly I have damaged both slots.

any other ideas, please?

Re: WARNING: Never Change Radio Band

cmantas — Mon, 02 May 2016 13:32:59 GMT

Yes, I finally fixed it with this:

http://www.honorbuy.com/forum/thread-360053-1-1.html

same process is explained here (try using google translate), and also here, however I think the first one is more concise.

Also you might need some qualcom drivers (QDLoader HS-USB Driver). I have uploaded in my google drive here, but you could also google it.

Be adviced:

a) you could brick your device - I nearly did mine.

b) it took me a whole morning, so relax and be prepaired to spend some time.

c) At some point, halfway through the process I got an error, something like “Not enough storage is available to process this command”. At this point I was essentially left with a brick.

However I installed everything in another PC, restarted the phone in fastboot, etc and did it again and (after a couple of tries), it woorked.

The link from the 'honorbuy' site is also for the global ROM, which is good.

Good luck!