Downgrading iphone 3g 4.0 iOS to 3.1.3

[tha_bandit]

MC doesnt matter in the 3GS sense, only important for ipod touches, anyways how did you originally jailbreak? if you used pwnagetool or redsnow then you can use pwanagtool 4.01 to create a ipsw and then simply restore to it in itunes (better to put your phone in recovery mode). also you have to check your bootrom (tethered jailbreak?, new bootrom, where you had to connect your phone if the battery died, restart, etc.)

helpful info from dev team:

iPhone 3GS

Summary: Currently, PwnageTool only works on previously jailbroken 3GS devices with the old bootrom.

If you have a Jailbroken iPhone 3GS with the OLD BOOTROM and you DID NOT use Spirit to jailbreak then you can create the ipsw with PwnageTool 4.0 and restore with your jailbroken recovery mode.
If you have an iPhone 3GS with the NEW BOOTROM this is NOT supported by PwnageTool 4.0 PwnageTool 4.01

[da9integ]

Thanks. Is the old bootrom 5.12.01? I have 5.12.01 an I'm
not sure if this is the old bootrom or if 4. Etc is the old bootrom?

[tha_bandit]

^thats baseband, bootrom is in the form: iBoot 359.x, you have to find a USB viewer utility to figure it out, however if would be helpful if you know what utility the iphone was jailbroken with or if it required a tethered jailbrake (before Spirit).

those number you mentioned are the baseband (modem firmware), since they are all unlockable you dont have to worry what baseband you are on, depends on if your iphone was jailbroken previously and has old/new bootrom

[sabad66]

Originally posted by eblend


I had this problem yesturday and figured it out, assuming you are doing a restore of your backup and jailbreaking?

This is what you need to do:

1. backup your iphone in itunes
2. Open itunes and hold SHIFT to select the ipsw file you downloaded of the firmware
3. Do a full restore of the phone (don't upgrade, upgrade = slow as shits from what I hear)
4. After the upgrade is done, go to Settings/General/About. Let it sit there for a little bit, or go in and out of the about screen, soon enough, a carrier update message will pop up on the PHONE, select yes to install it. DO NOT allow itunes to do the carrier update, as it will keep prompting you to do so, but it doesn't work)
5. After you do the carrier upgrade, do a restore of your iphone backup. Check and your internet should be working still.
6. If you want to jailbreak, do it now, and after it is all done, your internet will still continue to function.

This meathod is proven, got the sequence down yesturday, and verified with my friends iphone as well, since he had the exact same issue

Does your MMS work with that method? Which jailbreak version did you use?

[shakalaka]

I still have no MMS. I stopped trying after I got the 3G working.

[j.ng-]

on a side note, does anyone know if JBing is possible for a iPod Touch 32G (3 Gen)? Non MC model
I was also forced to updating to iOS 4.0 cause iTunes wouldn't let me restore my Touch

[sabad66]

There's a new redsn0w out, 0.95b5-5, supposed to solve the MMS issue. Check it out here:
http://wikee.iphwn.org/howto:rsbeta

[MGCM]

a friend of mine just did the upgrade and so far has had zero issues with it

[Lagerstatten.ca]

Fuck! Just installed iOS4 on an non-jb iPhone 3GS, now I can't downgrade to 3.1.3 anymore as all restores need to be verified with Apple now. Apple doesn't allow for you to restore to any other iOS besides the latest iOS4 for the 3GS.

Word of caution for those that are attempting. Not cool...I have a possible iBrick 3GS now...

[tha_bandit]

^ why do you want to downgrade to 3.1.3? to jailbreak? Anyways Spirit should be out soon to jailbrake any device on new firmware. don't worry about your phone being bricked, DFU mode can solve a lot of problems

[Lagerstatten.ca]

^ I know - I'm patiently waiting for the new Spirit Jailbreak to come out so I can JB/Unlock iOS4.

I wanted to downgrade back to 3.1.3 so I can JB/Unlock the 3GS phone - but now I'll have to wait.

Weird though - In Cydia - I did select the option to have my SHSH saved to their servers. But even after modifying my hosts file I couldn't get it to work. Still said that I was unauthorized to do the restore.

I'm just glad that I didn't brick the 3GS and atleast it's working and running iOS4 now (smoothly too). Hopefully they'll release the new Spirit Jailbreak soon.

Ultrasn0w is still the choice app for unlocking right?

[tha_bandit]

^yep ultrasn0w, works with everything at the moment.