The much anticipated downgrade for ipad baseband 6.15 has been released to downgrade to 5.13.04 baseband for 3g and 3gs users stuck on the ipad baseband.this will solve your gps issues caused earlier by installing the ipad baseband.Follow the steps given below to downgrade your baseband.
Here are the links to the required softwares
Following are the steps for the downgrading process
- Start Redsnow select “Extras->Select IPSW” button in redsn0w to tell it which stock firmware ipsw file you have used to install ios. (new-bootrom 3GS users can usually skip this step but it doesn’t hurt for them to do it too).
- Do a controlled shutdown of your iPhone (“slide to power off”). This step is very important to avoid mount problems when the ramdisk is running!
- Go back to the first screen of redsnow and click “Jailbreak” and follow the steps. Enable the “Downgrade from iPad baseband” checkbox, disable Cydia if you already have it installed, and click Next to proceed through the normal DFU ramdisk steps.
After the ramdisk gets launched and you see the running Pwnapple, you’ll eventually get to the “Flashing Baseband” step. THIS STEP TAKES A VERY LONG TIME to
complete and there won’t be any feedback while its running. Please
just let it be for the next 3-8 minutes! When the ramdisk has done its
job it will reboot the phone on its own.
4. If your the baseband is still at 06:15:00 after completing the process, just do it again. MuscleNerd says "the downgrade code minimizes risks but false positives are possible".
5. Many people who
saw "No signal" issues after the downgrade from 06.15 fixed it by
re-installing Mobile Substrate and/or Ultrasn0w
Now you can downgrade your 6.15 ipad baseband to 5.13.04 to fix the gps issues.3gs users with manufacture date upto 28th week of 2011 and all 3g users can use this method to upgrade to 6.15 baseband and then downgrade to 5.13.04 BaseBand.
WARNING
All iPhone 3G users can use this method to upgrade to 6.15 baseband and then downgrade to 5.13.04 BaseBand.
If you want to update your 3GS to 06.15 only to downgrade to 05.13.04 later you shouldnt use the ipad baseband if your iphone 3gs is manufactured after 28 week 2011 as it will brick your phone.to check your 3gs manufacture date, go to this site( http://www.chipmunk.nl/klanten... ) and enter your iPhone’s serial number in the given box. To find serial number, go to Settings >> General >> About >> Serial Number.