Strange WiFi problem on iPhone 3G after 3.0 update

-Jay-

We don't have problem with internet, we have problem with WiFi.....

My iPhone doesn't find any WiFi network... and I don't know if it is hardware problem or software....all we are waiting an answer from Apple... but Apple is sleeping...

or they dont care about us

Search for my earlier posts about it.
My (now sold) iPhone 3G 16GB could not connect to any network via wifi affter the 3.0 update. Tried everything, ex. the (for me ridiculous) freezer solution. Only the downgrade back to 2.2.1 solved this issue.

Can you tell me how can I downgrade ?!

Please

I got a 16GB 3gs iPhone. After the software update to 3.0.1. I can only connect to an unsecured wifi. I cannot connect to wifi secured by WEP key.

Interesting about downgrading to 2.2.1

About my problem, I can see wifi networks, but can't connect to any.

My phone is iPhone 3G 16G. This problem happens after upgrading to 3.0.1 (including jailbrake & unlock), returning to 3.0 doesn't have any effect.

I'm using iPhone 3G 16gb. After updating the firmware to version 3.0.1 stopped working module wi-fi. The module does not find any wi-fi network or my home wi-fi access point .
Recommended way to try it - the freezer.
At some time this method has helped me.
2...3 days, my iPhone 3G worked fine, but then stopped again to catch any network wi-fi.
It would be interesting to hear a response from the Apple inc., What they think about this...
P.S. My iPhone 3G's, bought the company Megafon.
P.P.S. Sorry for my bad English.

I guess this problem will not be addressed by upgrading or downgrading, so APPLE has not given any formal responds up to now.
You only have to replace new one on apple store, or change WIFI IC.

How to downgrade?

- Downgrade the firmware by downloading the 2.2.1 IPSW file from apple. Search for it in google. The install it by holding shift+'restore' button in iTunes and selecting the file.

- To downgrade the baseband (modem) - search for 'FuzzyBand' downgrader in Cydia, and follow the instructions.

Post your results.

@yonido, please post a link to the 2.2.1 original firmware.

A little more help regardind the downgrade would be nice, I tried and got error 1602. I also think the freezer test is ******** and I wouldn't put my phone in the fridge. I also never jailbroke the iPhone I don't intend to unless it would get my wifi back. Without wifi, it's not iPhione, it just Phone 🙂
I went to the only Apple representative in Romania (it's also the Orange service) and they din't want to replace my phone because I didn't keep the invoice the warranty :((
So I'm stuck with a big Phone, no wifi (wich I frequently), can't use the warranty (wich expires on the 7th of September according to Apple website). A little help from Apple would be really nice.

@cstroie, you can find more info about downgrading on page 37, halfway the page where I posted a link to iphoneclub. the first post is the guideline, but you only have to go up to step E, since those other steps are only for 2G phones

this is what it sais in a nutshell:
Please note that it isn't as easy as simply shift+restoring your device. You have to put it in DFU mode first, with a certain 3rdparty tool 😉 then when you shift+restore your iPhone, it gives you an 1301 error which is fine. then use that same 3rdpartytool to JB it, since that's the only way to get your iPhone running again after a downgrade. This is because there will be a firmware and baseband mismatch (you will still have 4.26 baseband which came with 3.0 firmware, but you'll be running the much faster 2.2.1 firmware now). You can downgrade that baseband with fuzzy as described above, but only if you have a really early 3G iPhone model

I did this downgrade and couldn't downgrade the baseband but at least now I can see my wireless (sometimes). It just drops out frequently and has poor reception, so it's not the true solution to our problem. A baseband downgrade (as yonido said earlier) would probably solve the sporatic part and fix wi-fi all together. But as Luis231 pointed out earlier, that might not help either

Geez. 39 pages on this thread and still no Apple fix.

Ever since getting my 3GS, my WiFi fluctuates, and I am sitting right next to my router right now, and see the WiFi bars change from 3 bars to 2 to 1 then back up to 3 etc.

This is very frustrating and it does not occur on my wife's 2G iPhone within the same network.

This is not only my router-specific either, as I still see the "fluctuating Wifi bars" when i am at work or other WiFi areas.

I've tried numerous "fixes" posted by helpful people here, and really don't want to downgrade OS. I also read thru 1/2 of this thread, and don't have time to sift through each thread it looks like, but judging from the size of this thread, this is a MAJOR problem affecting many people.

I am trying without succes to downgrade to 2.2.1. I;m entering DFU mode, I am selecting the 2.2.1 firmware (from here: http://www.sizlopedia.com/2009/01/28/iphone-221-firmware-download/) but then itunes tells me there has been an error (1600). Just no luck. Any ideeas?

Similar problem. Except I cannot even connect to wifi access point (Airport with Time Capsule). If I reboot the 3GS, or "reset network connection," I can connect to the access point. After a short time, I loose the connection and no longer see the access point. If I reset the network connection again, I'll see the access point for a short time. And the cycle repeats.

In addition, my battery life has plummeted.

Add me to the list. After 3.0 and 3.0.1 updates, the phone doesn't pick up WiFi signal from anyone, regardless of router make or settings. None of the common quasi-solutions (e.g. resetting network settings) work. Apple needs to get on this and push out the 3.1 update yesterday. Hopefully this time their Q/A is a little better.

Yep. Add me to the list: 1st gen that completely stopped connecting to any of my wifi spots after 3.0 update. So frustrating, and so tired of waiting for the update to fix something that always worked before. Was considering the 3Gs, but now I'm afraid to invest further with the iPhone until this issue is resolved.