I miss the fact that my SGS3 was not sold as a world phone like my Inc2. But I had read that there was the possibility that a later Verizon update might allow this capability for the SGS3 in the future. Now I read this thread and I am confused??
So for those of us with rooted phones I'd like to understand the following...
(1) Are our phones really capable of using domestic and/or international GSM SIM card use with the stock ROM from here (
http://xdaforums.com/showthread.php?t=1756885) without any software updates?
From phonescoop.com -
Samsung Galaxy S III (Verizon)
LTE 750
CDMA 850 / 1900
GSM 850 / 900 / 1800 / 1900
GSM supported only with update after launch
(2) If so, does anything need to change other than (a) the Device Info setting accessed through the Phone Info app and (b) the APN settings accessed through the APN Manager app?
(3) At what point is an unlock code required? In the past for my Inc2, I spoke with Verizon Global Services at 800-711-8300 and received an unlock code which was entered when I was overseas and put in the local country SIM card. When I spoke with Global Services today, they could not give me an unlock code as they said the phone was not capable at this time and was not in their system.
(4) Do I have to load a different ROM than what I have?
(5) Is there a US GSM micro-SIM I can get from a local outlet that would have a small amount of phone and data that I could use to test out how this might work?
(6) Are there any major issues that have developed that should discourage this attempt?
(1) According to the |OP|, if you are unrooted, when you put in a domestic gsm sim, the phone forces you to enter a generic code to unlock the ability to use other sim cards. I am rooted with the "stock" rooted rom from the same thread by invisiblek that you posted in your question. I was able to cut my T-Mobile prepaid sim card into a micro sim and use it in the SGS3 (although the sim was a little too thick and slightly difficult to retrieve when trying to get it back out), and YES, after using phone info to switch to GSM/WCDMA/LTE mode, it picked up full T-Mobile signal and I had voice and messaging with full signal. Due to the apn settings being locked on this phone though, I was unable to connect to an apn and get data, so for now, only voice, no data, with gsm sim card. It did however NOT ask me for a code the way it did from |OP|, I was rooted, he wasn't, so we're guessing that's the reason for no codes. So yes, it was confirmed that it will let you use a domestic sim either rooted (no code required) or unrooted (unlcok code required), but without data for now.
(2) No
(3) When you turn the phone on with a different sim (if you're unrooted). Verizon supposedly provided some generic sim unlock codes in the contract that you were signing when (and if) you preordered. That's where the |OP| got his codes from. Although it never asks for codes if you're rooted, it does give you a continuous "ongoing" notification in the notification pull-down that says "non-Verizon sim", and you get a sim symbol with a question mark in it in the top left of the notification bar. The |OP| didn't complain about that, so I'm guessing he didn't get that because he was unrooted and had to enter the unlock code, so he won't get that notification, but rooted phones that never entered the unlock code will. To get rid of that, you may have to flash the fully stock, unrooted rom, put in the gsm sim, let it ask you for unlock code, then after you unlock it, root your phone again. That's just a guess. The ongoing non-Verizon sim notification does not keep the gsm sim from functioning though as long as you use phone info to change your cdma mode to gsm.
(4) If you're rooted, just to get gsm voice service, probably not, but if you want data, you may have to flash a different rom that will allow you to modify apn settings since the stock Verizon (rooted or unrooted) has that option locked. An apnedit app may be able to let you edit the apn settings, but we are unaware of any right now. Any gsm version rom (like AT&T stock rom) will probably let you change apn's, but at the moment their roms wouldn't work with our kernel or radios.
(5) You can get prepaid micro sim for AT&T or T-Mobile, I recommend AT&T, because in the case that our phone is WCDMA or HSPA+ capable, like the AT&T version, which I assume it is if all the radio's are the same (except tuning of the LTE band which is on a different band of the 700 MHz for AT&T than it is for Verizon, so it will probably never work with another carrier's LTE service) then you'll be able to get AT&T's 3g (HSDPA) or "4g" (HSPA+) because those are on 1900 MHz, while with T-Mobile you'd only get their 2G (EDGE) on 1900 MHz because T-Mobile's 3G and 4G HSPA+ are on 1700 MHz, and this phone cannot receive 1700 MHz. You can get either AT&T or T-Mobile micro sim on eBay fro $3-$4 unactivated, then you can call their CS or go to their store and get prepaid service activated for your existing phone. You might not want to show them your "unlocked" Verizon SGS3 though, so use a regular GSM phone to activate prepaid service (you might even be able to get the sim in the store if you have a gsm phone that takes micro sim). You could also purchase a go-phone with a regular size sim card, activate it on a prepaid plan with 3G or 4G data, then use a sim card punch cutter and turn it into a micro sim, but be careful not to damage the card when you do that.
(6) When you're done "playing" with your SGS3 in GSM mode, if you go into apn list in settings > more settings > wireless network, you'll see all the Verizon apn's are gone from the list. If you just turn off at this point and swap to your regular Verizon sim, it may not get service right away, and you'll get a yellow triangle with exclamation on the top left. This may make you "panic" for a few minutes and think "what did I do?" You can either keep resetting a few times (after having to manually switch to cdma mode again in phone info), until you get your Verizon apn's and service, restored, or you can switch back to CDMA/EVDO/LTE in phone info BEFORE you power off when you are still using your GSM sim, and this will save you a little bit of the headache and panicing after you reset the phone power. you want the phone to already be in cdma mode again before you put your Verizon sim back in, otherwise it'll be confused and search for a while, I recommend avoiding that.
Hope this helps. If it did, please hit the thanks button.
