Field Test Mode?

Yep, they changed the code to access it.

Congratulations on being one of the few people here able to consider investigating issues scientifically rather than announcing conclusions with no real basis whatsoever. You're in a minority.

It does not work on the 3GS anymore either. I guess AT&T does not want people to know just how bad their service really is. It is going to get much worse before it gets better.

It was changed because some of the information it provided could have been used for sniffing other people's data as it travels over the network. It was never meant to be out in the wild. 🙂

I'm still hunting for the new one. Will post back if I locate it.

http://steve.grc.com/2010/06/26/iphone-4-external-antenna-problem/

Worth a read. At least this is an opinion from somebody with an electronics engineering background. 🙂

We need a rogue AT&T tech for this one. I suspect AT&T buried the code so that we couldn't actually tell how badly they are covering many areas in order to finagle that "more bars in more places" slogan of a while back

Now that they are "rethinking possible," us little people shouldn't be concerned with how thin actual field data would show the coverage to be.

Finally, with the new ETF fees being so high, and actual coverage at your domicile being a way towards the ETF being waived, they aren't going to be very inclined to let people have actual numbers.

Nonetheless, I'll try googling some of the mod forums for new gsm codes. Those guys can figure out how to so many things so I'm sure somewhere they've already sniffed this feature out or at least can tell if it's even still there. I wouldn't be surprised if AT&T whacked acces to it through the carrier file in the baseboard.

Speculation is that it's not there. http://www.howardforums.com/showthread.php/1650559-Field-Test-Mode-Number-on-OS4 -GM-AT-amp-T-Carrier-File-7.0?p=13806370

I was able to replicate the USSD test response which is mildly amusing by dialing *3001#54321#

See this page too. http://www.mediabistro.com/mobilecontenttoday/iphone/nofield_test_mode_diagnostic_tool_on_the_iphone_4165801.asp?c=rss

I bet it's there but locked behind some nasty doors. Or, I bet there's somebody already trying to figure out how to get an app approved that does it or at least reports gsm info.

AS soon as they've got the jailbreak working for iOS4 you can replace the bars with a meaningful read-out that way.

Field test mode is still there somewhere and if it's there somebody will find it.

Sp4ck wrote:
AS soon as they've got the jailbreak working for iOS4 you can replace the bars with a meaningful read-out that way.

Field test mode is still there somewhere and if it's there somebody will find it.

No. Jailbreakers have already mentioned that the field test app was removed in iOS 4's firmware internals, so this is why the code doesn't access it.

I had it working on my iPhone 4 after I upgrAded from my iPhone g3. I was stating at -99 then it would go to -109 then to -113 someone suggested resetting the network settings and it turned I off!! So it must be there- wound if I could reinstall my iPhone back a few days???

The application may have been removed from the iPhone OS (although I doubt it) but the phone's hardware is still monitoring and reporting the same details as it was before. It would be perfectly possible to install a replacement app on a jailbroken iPhone that replaces the one Apple have removed or hidden.