No Service with T-Mobile on a GPP activated 4S. Please help!

Discussion in 'iPhone Tips, Help and Troubleshooting' started by Ph4zon, Oct 11, 2013.

  1. Ph4zon macrumors newbie

    Joined:
    Oct 11, 2013
    #1
    Hey everyone. First of all, I apologize if this is not the right place to post this, but I've been working on it for days now, and I'm getting desperate.

    I have an iPhone 4S that is locked to Softbank. iOS version is 7.0.2. I'm trying to use a GPP interposer from China3GPP to get it to work with a T-Mobile prepaid SIM. It is advertised as working with iOS 7, and I heard a lot of positive feedback from Japanese people in the same position as me.

    The interposer allows me to access the phone as if it was unlocked, but my T-Mobile SIM displays "No Service" most of the time. Occasionally, if I remove and reinsert it, it will display T-Mobile, and cycle through "No Service" > zero bars > one bar, repeat loop. My number is displayed as "Unknown," and I am unable to use the phone to make calls or send texts.

    Inserting my friend's Verizon SIM into the Phone resulted in "No SIM" where the carrier would normally appear at the top of the Phone, but the iPhone recognized the phone number from the SIM Card, and a new 3G option appeared under Settings > Cellular. My T-Mobile SIM did not provide service on his Verizon Lumia 520.

    I've tried setting it up with both epc.tmobile.com, and fast.t-mobile.com APN settings.

    Manually choosing T-Mobile or T-Mobile (3G) as the carrier does not resolve the problem. I've tried formatting the phone, and done the GPP unlock process multiple times. I'm completely out of ideas, and I'm getting really bummed :(. I'd really appreciate any advice.
     
  2. okwhatev macrumors 6502

    Joined:
    Oct 19, 2005
    #2
    Do you have the new R-SIM 9? I know some of the GPP ones are supposed to work with iOS 7, but the R-SIM 9s are specifically made for iOS 7. You've applied any patches available for your GPP? Did your GPP model specifically say it was for the iOS version that you have installed? Note that interposers' hacks are heavily hardware based, and although they technically could be updated with patches, they often aren't simply because they'd rather sell a new one. Things really heavily changed in iOS 7 baseband wise, so I wouldn't be surprised if they are dramatically different in interposer sensitivity.
     
  3. Ph4zon thread starter macrumors newbie

    Joined:
    Oct 11, 2013
    #3
    The GPP interposer I have specifically stated that it should work with iOS 7.0, although I believe 7.0.2 (which is on my device) was rolled out after I purchased the interposer. Could this cause a significant problem?

    I went with one from china3GPP first of all because it was recommended by other people with Softbank locked iPhones, and because they indicate that a 4S should be fully functional without any mention of patches. I can't be certain, but it seems like they are the ones who originally create the GPP interposers, and other groups like NeterTeam resell them.

    As the china3GPP website is in Chinese (with only poor English translation), I can't find any mention of patches. Do you think NeterTeam's GPP patches would work with my china3GPP interposer?

    I'll definitely look into R-SIM 9 as well, although I'd prefer not to have to spend more money.
     
  4. BMdubLOVE macrumors newbie

    Joined:
    Oct 27, 2013
    #4
    CHINAGPP works great on Iphone 4s Sprint 7.0.2

    The chinaGPP Rainbow Sprint, on these you never have to put in activation to get it working, instead simply adding the neter3to2.ipa onto your iphone through itunes and waiting a great while (i waited luckily 20 min) before getting the "phone activation failed" and whoAla! the phone gets signal. got mms working with 3g data no problem. Of course I have to add that chinaGPP's instructions are very clear to do a factory reset on iphones running 7.0/7.0.2 before doing the process. Hope this helps< Pm for any specifics.
     
  5. Ph4zon thread starter macrumors newbie

    Joined:
    Oct 11, 2013
    #5
    Solution

    Hey, I just wanted to come back to this thread to thank everyone who replied. I ended up getting an R-SIM Air, and after a long wait for it to arrive, had a lot more success. It was simply a matter of popping the new T-Mobile SIM in along with the interposer, and selecting the original carrier that the iPhone was locked to.

    To further clarify for anyone else in my position (the R-SIM site has some pretty poor English translation as well), here are a few details.

    -My iPhone is locked to Softbank, and I'm running iOS 7.0.2.
    -I got the card from the official R-SIM Air website. I've heard older versions of it purchased secondhand are less likely to work.
    -In my case, no patching as necessary.
    -Before selecting Softbank (JP SB), I had to select "Mode2 (4S ios6&7) 3G"

    At this point, I'm green across the board. I hope this info can save someone from the hours of frustration I went through.
     
  6. c0ry, Jan 7, 2014
    Last edited: Jan 7, 2014

    c0ry macrumors newbie

    Joined:
    Jan 7, 2014
    #6
    solution

    I was able to get a GPP from china3gpp.com to work on my phone, and I thought I would share the solution since I was unable to find any solutions online. If you translate the Chinese version of the web page and go to the software download tab, it says to point your iPhone browser to 3to2.china3gpp.com, and download the patch.
    Once you program the GPP, and insert it along with the SIM you are trying to use, apply the patch, and you should have service after you restart your phone. Hope this helps someone in the future that has the same problem we ran into.
     
  7. Surendrakumar macrumors newbie

    Joined:
    Jan 16, 2014
    #7
    Can you tell me what the website is that you purchased this. I have a softbank phone i am unable to use.

    Thanks

     
  8. seecoolguy macrumors regular

    seecoolguy

    Joined:
    Nov 28, 2007
    #8
    I just picked up a gpp off of ebay, for my Verizon iPhone, I followed the instructions from the seller and I was able to get the Verizon iPhone to power up and connect to the TMobile network. although the APN settings were wrong which at first I couldn't get any data.

    after I visited TMobile support site for APN settings for the iPhone I updated it and now I can get 2G data but not 3G. IIRC, isn't the Verizon iPhone the same model like the AT&T model? thus it should have the same antennas.

    I have an unlocked iPhone4 and it was running with the TMobile sim and gets TMobile 3G signal, but the Verizon iPhone4S only seems to connect via 2G, has anyone else ran into this?
     

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