No signal on unlocked iPhone 3G

Hi,

I have an iPhone 3G iOS running 4.2.1 that I have ran redsn0w 0.9.6rc8 off my Mac to JB. I then ran Ultrasn0w in Cydia and tried to unlock it. All went well, but I am getting either a very low signal or no signal off my new SIM chip.

I am wondering what is happening and how to fix it. Do I have to update my baseband to 06.15.00? Given all the warnings I chose not to. I think my phone didn't need it, my serial number is 88902... So that is the second week of production? I think? and thus no need. But it is useless at this point.

Any advice, help or direction would be greatly appreciated.

Matt

What is your current baseband? Ultrasn0w doesn't currentlywork with it is 5.14, 5.15 or 5.16 series basebands.

Your phone was made in week 2 of 2009 - so it's not possible to downgrade your baseband again if you upgrade to 6.15 baseband.

The iPhone 3G was introduced in the middle of 2008 and it is only the iPhones made before week 27 of 2008 that can have their baseband downloaded.

Thanks, This is new information. My baseband is 05.15.04. So do I have to upgrade the baseband to 06.15.00 or do I need to use different software to unlock my phone?

PS, I just dod a quick check on my baseband and see that it has to be upgraded to 01.15 to work if I am running 4.2.1. Can I downgrade my systems firmware and then use UltraSn0w? If that even possible? I really want to keep my GPS working on the phone.


Note: I just finished hours of poking around on the web for more information on this issue. I found that I could try to downgrade using Fuzzyband. I tried but my Bootloader was not supported. So right when I was about to bite the bullet and upgrade to 06.15.00 I saw in my Cydia "This device has a pending TSS request". I remembered, I hit the "Make Life easier" option. So am I right in thinking that if and when Saurik shows my device as being backed up can I downgrade?

But the big question is: When will that happen or has Saurik has stopped backing up peoples devices? That is the rumor I read.

You are getting different things mixed up, here are some facts.

Downgrading the OS and downgrading baseband are two separate things - downgrading the OS does NOT downgrade the baseband
On the iPhone 3G, the ONLY way to downgrade baseband is if you have baseband bootloader 5.8 (your phone is too new and probably has baseband bootloader 6.4). You have confirmed this via Fuzzyband.
Upgrading the OS often also upgrades the baseband.

Saurik will only save your SHSH for iOS 4.2.1 - it is IMPOSSIBLE to save a SHSH for any older iOS version any more.
SHSH is really only a roadbump for the 3G (because it is not checked in hardware on the iPhone, that extra security was added in the 3GS) - it can be bypassed.
A saved SHSH won't help you downgrade your baseband on any model iPhone or 3G iPad.

Saurik's server can take days or even weeks to save your 4.2.1 SHSH - your "TSS request" sits in a huge queue on Saurik's server and you can't do anything to speed it up. Even when your SHSH is backed up, it may take even longer before this is displayed to you when you open Cydia. This doesn't mean Saurik is stopping backing up peoples devices. It just means that Cydia has millions of users/devices and to improve overall performance some tasks like saving a SHSH and updating the line at the top of the Cydia screen listing which SHSH you have saved are not updated instantly.