Please Help(No service)

[tak_touch]

Hi Guys

I have Iphone 3G, I tried to upgrade the firmware to 3.0, but however, it's not working fine so I try to downgrade it. But now the iphone already recover to normal, only the problem it cannot detect my sim card. I try to reset the network setting in the iphone still cannot help. I find out some post mention that the modem firmware has problem on this, is't true?
Now currently firmware is 2.2.1(JBed) and the modem firware is 04.22.01. Need your help urgently, thanks

 

[Jeremy]

http://forum.theiphoneblog.com/iphone-developer-forum/170532-downgrading-3-0-back-2-2-1-a.html

 

[tak_touch]

HI

Thanks for your reply, I did downgrade back to 2.2.1, but still cannot work. BTW i will follow the step and doing again.
But how about the modem firmware, how to downgrade to lower verison?

 

[Jeremy]

You can't. You are stuck with that baseband. And redo the steps I listed in the link. I know exactly what you are doing wrong to get no service. If you read carefully you are not supposed to jailbreak your phone... You simply do the first step of quickpwn. That's it.

 

[tak_touch]

Hi,

I tried to redo the step, it's the same. The phone already back to 2.2.1 now, but it still cannot read my SIM card(Showing no service). Is't I missing some of step that the phone cannot use? I'm not use AT&T sim, I'm using Singtel(Singapore). Is't unlocked by the SIM card??

 

[Jeremy]

Hi,

I tried to redo the step, it's the same. The phone already back to 2.2.1 now, but it still cannot read my SIM card(Showing no service). Is't I missing some of step that the phone cannot use? I'm not use AT&T sim, I'm using Singtel(Singapore). Is't unlocked by the SIM card??

If your phone was unlocked via software then I'm afraid you have pretty much rendered your phone useless. Now if it is factory unlocked then I don't know what you are doing wrong.

 

[tak_touch]

yes, I will purchase the Turbo SIM card to try....><"

 

[Jeremy]

I could be wrong but I don't think the Turbo SIM card will work either.