How I Got my iPhone 3GS Running on T-Mobile
A friend of mine sold me her iPhone 3GS for a scant $30. While I didn’t necessarily want it as a phone, I started to look in to how to jailbreak and unlock it for use on my T-Mobile service. Her phone was sold by AT&T and was locked to that carrier, but both AT&T and T-Mobile use compatible GSM technology so it’s just a matter of unlocking it to use on other carriers.
I realize I’m already talking jibberish to some folks, and I had a pretty steep learning curve as well so don’t feel bad. Jailbreaking is using a software hack to modify your iPhone to be able to install software from sources other than Apple. Unlocking involves hacking the phone again to remove the hardware lock to a particular cellular signal or carrier.
For this particular phone though, that wasn’t as simple as it sounded. This phone runs iOS 5.0.1 and when the operating system was updated, it also updated the modem firmware (which gets the cellular signal) to 05.16.05 which rendered past unlocks unusable. Plus there were some 3GS phones that aren’t jailbreakable at all. I did a lot of internet research and the best information and tutorial I found was on everythingapplepro.net:
My phone was able to be hacked thankfully (I had to check the serial number – make sure you do as well when requested). The issue that arose was that while jailbreaking would be relatively simple, unlocking would be trickier. It’s impossible to unlock the iPhone with that particular firmware for the modem (5.16.05). I tried at first and it just crashed and I had to restore my phone. It turns out that to unlock the phone I would need to get a different firmware for the modem (6.11.00), which in many cases interferes with the GPS functioning of the phone.
I weighed the pros and cons of losing the GPS and decided to take the leap and try and unlock the thing. Plus my wife needed a replacement phone and I could give her my old one.
I used a program called Redsn0w (that “o” is a zero btw) to jailbreak the phone and followed the instructions on the video. It took some practice getting the phone into DFU mode (sort of like safe mode in Windows). Definitely make sure to follow the instructions down to the exact detail, and make sure to back up your phone to iTunes before going too far.
When running Redsn0w I had to check off to install Cydia and downgrade the modem baseband to 06.15.00, which is actually for the iPad. You can’t go back if you do this though, so just bear that in mind.
It took a little while to get the hang of getting the phone into DFU mode as well as getting redsn0w to recognize it, but once it worked it pretty much does itself.
After jailbreaking and installing Cydia (an “app store” for non-Apple iPhone programs) on the phone I downloaded another program called ultrasn0w (again that’s a zero) to unlock it. I put my T-Mobile SIM card in, rebooted, and…
…nothing at first. I got a “no carrier” message, and I thought I’d just wasted my time (and GPS) for nothing. Lots of people had this problem, but I had trouble finding a clear answer to it. I started tinkering with the settings a little and figured out what the problem was. I went in to Settings>General>Network and turned off “Enable 3G”. I also switched it on to airplane mode once or twice. Then the phone caught the T-Mobile signal and I did the happy dance.
I get great reception, but the phone is limited. The GPS is not funtional – at least when the cell network is on – and data only works on T-Mobile’s EDGE network, which is slower than what the phone is capable of. However I am fine with surfing and doing other stuff when connected by WiFi and limiting my other data use when on the network.
The files required that I mentioned are all available at the link above on everythingapplepro and if you’re thinking of unlocking your phone for T-Mobile this was the most informative guide for me. There’s lots of help out there so keep looking but be careful and do your homework before trying anything.
Since the date of this post, I managed to order a factory unlock of my phone through Ebay for under $10. That solved a frequent problem of mine, which was being unable to update iOS until the update was jailbroken. Now there’s no concerns about losing my unlock or jailbreak!