[*sim] T-Mobile UK dropping Signal, No Service , No SIM messages
I hope one of the Moderators can make this a sticky until we get to the bottom of the problem.
It seems there is a problem in the UK with the T-Mobile Network & iPhone through the SIM Proxy Devices. (aka TurboSIM, China3gpp etc).
I was skeptical when I first heard about this problem, but I have seen it for myself!
Because the problem initially looks like it could be a contact problem, I imagine a lot of people have not reported it yet or are persevering with it!!
The symptoms are that when trying to use the iPhone with T-Mobile in the UK through a TurboSIM or similar clone device, the signal drops out and the phone suffers from "No Service" and "No SIM" messages.
I have personally seen this with 2 different customers iPhones and did some testing myself with 2 Brand new iPhones.
In my tests, the T-Mobile service comes up fine with 3 signal bars to begin with, but if left for a while, you can see the phone going down to 1 bar or "No Service" and then it pops back up to 3 bars. It can do this a few times before dropping out to "No SIM". Sometimes it will happily sit there with 3 bars until you try to do something like make a test voicemail call or send an sms etc. Whilst the call will go through fine, once you've hung up, the sequence of bad to no signal and no sim will commence!
I started to research it and a simple google search found a few other threads here on other forums backing up the problem:
In all cases, I was able to pop another SIM (like Orange or Vodafone for example) into the same phone with the same TurboSIM and not see the problem! (now thats strange).
Bladox is sending me one of their other devices which will allow me to monitor the traffic going between the iPhone, TurboSIM and T-Mobile SIM to see if we can identify what is causing the problem.