Hey all, I am planning to buy a used iphone 3GS which I was told was never jailbroken before so no SHSH saved unfortunately, and it is right now on the latest 5.0.1 iOS. I believed this is also a new bootrom 3GS, so my question is can I still use ultrasn0w to unlock when I update the baseband to iPad baseband using the latest redsn0w, or because I'm on 5.0.1 the iPad baseband will no longer work? I don't want to rush into doing things and brick this iphone. Thanks all!

You should still be OK to upgrade to the iPad baseband on this model. Of course, make sure it's not newer than week 35 of 2011, but if it's used, it shouldn't be. iOS 5.0.1 doesn't block the 06.15.00 baseband from working, but a high percentage of people had to re-flash it after upgrading to 5.0/5.0.1 -- but that really only impacted people who had 06.15.00 prior to upgrading to 5.0.1. ultrasn0w 1.2.5 will work on this as well. Make sure that you use redsn0w 0.9.10b3 to jailbreak (if you use b1 or b2, make sure you add the 'Corona 5.0.1 untether' package from cydia to fix ultrasn0w and the launchctl issue).

Standard warnings apply, that I'm sure you already know but for the sake of saying 'm:

1) This is permanent, you can't undo it. There's no downgrading the baseband once this is complete.
2) There's a 99.95% chance your GPS is going to stop functioning entirely when you do this and never work ever again.
3) You will only be able to upgrade iOS in the future by making no_BB custom firmware and using Pwned DFU mode to recover.
4) Your phone will obviously be viewed as out of warranty by any Apple Genius that happens upon it.

Let me know if you have any problems but you should be OK. There are some posts from people saying that they had to use SHSH to get down to 4.x, install iPad baseband, then get back to 5.0.1, but I can't find anything definitive that states that's a requirement. You should just be able to use PwnageTool/redsn0w to flash the baseband to your iOS 5.0.1 phone.

Originally Posted by n1ckn4m3

You should still be OK to upgrade to the iPad baseband on this model. Of course, make sure it's not newer than week 35 of 2011, but if it's used, it shouldn't be. iOS 5.0.1 doesn't block the 06.15.00 baseband from working, but a high percentage of people had to re-flash it after upgrading to 5.0/5.0.1 -- but that really only impacted people who had 06.15.00 prior to upgrading to 5.0.1. ultrasn0w 1.2.5 will work on this as well. Make sure that you use redsn0w 0.9.10b3 to jailbreak (if you use b1 or b2, make sure you add the 'Corona 5.0.1 untether' package from cydia to fix ultrasn0w and the launchctl issue).

Standard warnings apply, that I'm sure you already know but for the sake of saying 'm:

1) This is permanent, you can't undo it. There's no downgrading the baseband once this is complete.
2) There's a 99.95% chance your GPS is going to stop functioning entirely when you do this and never work ever again.
3) You will only be able to upgrade iOS in the future by making no_BB custom firmware and using Pwned DFU mode to recover.
4) Your phone will obviously be viewed as out of warranty by any Apple Genius that happens upon it.

Let me know if you have any problems but you should be OK. There are some posts from people saying that they had to use SHSH to get down to 4.x, install iPad baseband, then get back to 5.0.1, but I can't find anything definitive that states that's a requirement. You should just be able to use PwnageTool/redsn0w to flash the baseband to your iOS 5.0.1 phone.

I have no clue if it has the old bootrom at week 35 and earlier. How do I check this again by looking at the serial number? Will it cause a problem if it is after week 35? There have been several 3GS made with new bootrom eventhough it's now used. I believe it's the 4 and 5 digit serial number right? What do I look for?

Yes -- you'll want to look at the 3rd digit (last number of year the phone was made, 2007 would be 7, 2008 would be 8, 2011 would be 1, etc.) and then the 4th and 5th digit. If your 3rd is 1 and your 4th, and 5th are 35 or higher, the iPad baseband will brick your phone, but it would be pretty difficult to have a used phone at this point that was made newer than the middle of last year. The reason you want to be specific about this is that there is a hardware change that happened in the middle of 2011, and any phones made more recently than the 35th week will 'accept' the ipad baseband, but it will blank IMEI and MAC, unrecoverably.

Beyond that, I don't recommend using the s/n method to determine your bootrom -- there are easier ways to do this now (as I recall f0recast can do that properly now though a lot of its other information is suspect), and using the s/n if you're on the fringe can lead you to thinking you have an old if you have a new and vice versa. It's worth finding out properly first before doing anything, but the odds are you have a new bootrom phone that's old enough to handle the iPad baseband. Old bootrom phones are in extremely short supply these days, but you definitely want to know for sure.

Here are a few methods for finding out:

http://www.hackint0sh.org/f136/16285.htm
http://www.iclarified.com/entry/index.php?enid=3570
How To Check if Your iPhone is Tethered, Unlockable and BootLoader Version with F0recast

Some are easier than others, but all should be accurate.

Originally Posted by n1ckn4m3

Yes -- you'll want to look at the 3rd digit (last number of year the phone was made, 2007 would be 7, 2008 would be 8, 2011 would be 1, etc.) and then the 4th and 5th digit. If your 3rd is 1 and your 4th, and 5th are 35 or higher, the iPad baseband will brick your phone, but it would be pretty difficult to have a used phone at this point that was made newer than the middle of last year. The reason you want to be specific about this is that there is a hardware change that happened in the middle of 2011, and any phones made more recently than the 35th week will 'accept' the ipad baseband, but it will blank IMEI and MAC, unrecoverably.

Beyond that, I don't recommend using the s/n method to determine your bootrom -- there are easier ways to do this now (as I recall f0recast can do that properly now though a lot of its other information is suspect), and using the s/n if you're on the fringe can lead you to thinking you have an old if you have a new and vice versa. It's worth finding out properly first before doing anything, but the odds are you have a new bootrom phone that's old enough to handle the iPad baseband. Old bootrom phones are in extremely short supply these days, but you definitely want to know for sure.

Here are a few methods for finding out:

http://www.hackint0sh.org/f136/16285.htm
http://www.iclarified.com/entry/index.php?enid=3570
How To Check if Your iPhone is Tethered, Unlockable and BootLoader Version with F0recast

Some are easier than others, but all should be accurate.

Really, so the new bootrom with the ipad baseband will brick it completely? I could have swore that I updated the baseband for someone with a new bootrom 3GS and it worked They can insert tmobile sim and use it. So what you are saying is I can still have a new bootrom as long as they didn't past week 35? When did they start putting in a new bootrom that works with ipad baseband? Sorry I'm a tad confused.

Nope, never said the new bootrom with ipad baseband would brick it, but we talked about so many different things it's easy to get confused.

The only phone that will brick if you apply the ipad baseband is a 3GS that was made after week 11 of last year (2011), so any phone with a S/N where the 3rd, 4th, and 5th numbers are 135-152 will brick if you apply the 06.15.00 baseband.

When checking on the bootrom version, the bootrom change happened in the 40th week of 2009, so any phone with a S/N where the 3rd, 4th, and 5th numbers are 940-952 or 000-052 *should* be a new bootrom, where 900-939 would be old bootrom. In any case, that's not a 100% accurate way to tell so it's not recommended. You'll want to use one of the other methods above, but I think you're pretty clear on that anyways.

That help clarify?

hello n1ckn4m3, I had an iPhone 3gs. It was originally locked to AT&T but I jailbroked and unlocked it and was using it with Fido. Yesterday I replaced it with a new 3gs at Apple store, They said the new one would be locked like old one on AT&T and I didn't mind because I thought I'll jailbreak it and unlock it like the old one. I found out by using Forecast v1.3 that its serial is QR151xxxxx which means week 51 year 2011.

1-So now I shouldn't try to flash baseband 6.15.00 ? right ? what can I do to unlock this new phone (3gs,New Bootroom, iOs 5.0.1, baseband 5.16.05, locked to AT&T ) ?

2- If i can't do anything about it , any chance i can return it to apple store for my money and my old iPhone, should i ask them to change it with an unlocked one ? what do u think i do ? i can not sell this iphone as i am in canada and no one want an at&t unlocked iphone here , right ?

thx a lot , waiting for you reply

1) Unfortunately, you're correct. The phone you have has a baseband that cannot presently be unlocked. Even a Gevey SIM will fail, it's got too new of a baseband. The iPad baseband would brick the baseband chip and stop your WiFi/Cell from working at all.

2) It's worth a shot, but historically they will not accept a return without charging you a percentage of the purchase price, depending on consumer laws in your area. If you need an unlocked device, at this point the only one you can be guaranteed will be unlockable when you purchase it is a factory unlocked phone. iPhone 4/4S will be on 5.0+ with a baseband that cannot be unlocked, 3GS will be a new bootrom with a baseband that cannot be unlocked and cannot be upgraded to 06.15.00, and none of the current models are susceptible to the Gevey SIM interposer hacks, so if you need an unlock and you're buying a new phone, your best bet would be to buy a factory unlocked one (or buy a used and good condition one off of ebay, just make sure you know the important info before you buy, bootrom, iOS version, SHSH on file, baseband, etc.)

Hi n1ckn4m3 , I went to the Apple store and asked for my money and old cell back, told me the cell was shipped already and they cant give me back my money.I asked them if they can replace the new one with another one that is made before week 35 year 2011 , was told that the one I got (week 51 year 11) is the oldest they have cauz that's how it works ( first manufactured , first out), After arguing with the manager they accepted to refund me and i was promised they will try to return my old iphone. I decided to get the 4S unlocked like u adviced. Just wanted to share the story for anyone who might be in the same situation. Thank you for helping me out.

ok. im pretty much just as lost as he is. here's my situation.. i got a new iphone 3gs and it was made in the 46th week of 2011. it is running on 5.1 and is on a tethered jailbreak. the modem firmware is 06.15.00. from what im hearing, i cant unlock this phone. but since its on 06.15.00 is it possible? any help will be appreciated.