as you say Guarroman, i think also, our problem is caused by a temperature sensor default, i have changed my Comm Card and now i don't have any problem.
I have the same itunes, applications and so.

Tomek, I have an iPhone 2G, so when it is upgraded with firmware 3.0 the baseband is not updated, my baseband is 04.05.04_G.

Now I have downgraded the iPhone to 2.2.1 again.

toto74742001, yes maybe changing the comm card is the best and fastest solution, any tutorials there?

For tutorial, i follow the one explain here: ifixit.com, without disconnecting the Main Board.

so you guys with this problem all with Jailbroken iPhones?

so it's a hardware issue, right? it looks like there are a lot of people who suddenly got past the expiry date of their wifi chips...

same story here iphone 2g 2.2.1 wifi either not finding anything or just dropping immediately.

Great work on trying to solve the wifi issue guys! This is one of the most complete forums regarding wifi I found... But still, I`m stuck, I have a 3G - FW 2.2 - BB 02.28.00 - Jailbroken (Quickpwn) and Unlocked Yellowsn0w 2.6.
Without my WiFi, I cant access my freakin iphone on terminal. I dont knwo what else is left to do. Did several restores and nothing... Anyone got any updates or ideas (besides freezing which is retarded, I mean, putting a phone in the freezer??? WTF?)

Help Guys... Cant afford to pay for each KB downloaded on this crappy carrier down here in Brazil..



Not so different from microsoft products after all...

Hi, everyone!
I have the same Wi-Fi problems - iPhone 2G (BB 04.05.04_G, OS3.1.2 + Unlock + Jailbreak).
iPhone sometimes works good for some minutes or seconds in home/office Wi-Fi networks, sometimes it finds a wi-fi network, but can't connect to it and the most of time it even doesn't find any wi-fi network.
As i observed, wi-fi works good when iPhone is "cold" (iPhone was not in active use just before and its back cover is cold) and in some minutes wi-fi gets lost.

I read a lot of forum posts about such problems:
http://www.hackint0sh.org/f127/58137-3.htm
iPhone Wi-Fi failures caused by battery heat? | iPhone Atlas - CNET Reviews
iPhone Wi-Fi failures caused by battery heat? - Soa - IPhone-Wi-Fi-failures-caused-by-battery-heat- - AppleSource
and many others...
And I found a little workaround, which helped me personally. I'm not sure that it will help someone else, but you could try without any risk for your iPhone

I just opened SIM-slot and removed SIM card from my iPhone. iPhone caught wi-fi in some seconds after this and worked normally in wi-fi network for next ~30 minutes. I put SIM card back in iPhone - iPhone caught GSM networkm but wi-fi is still working for 20 minutes. After this I rebooted iPhone - wi-fi still works for 30 minutes more...
I hope this is the solution.
If you have mentioned problems with wi-fi - try this way, may be it will help you!

I have seen you valuable posts about wifi, these issues needs to be seriously solved by iphone developers. Hope to find a solution as early as possible.

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