Follow the instructions posted below to update your iphone 3gs or 3g to 06.15.00 baseband and jailbreak it on ios 4.1 /4.2.1. a) download the original ipad 3.2.2 firmware ipsw file from here (this version of ipsw is required for 06.15.00 baseband).. Only for 3gs users with 6.15.00 bb or those that want 6.15.00 and know about potential loss of gps. very important that you have old boot rom – new boot rom may/will likely kill the gps functionality on the iphone.. Once you put the ipad baseband on an iphone (6.15.00) you cannot do normal itunes upgrades anymore. if you give somebody a phone with ipad baseband make sure they know they cannot do normal upgrades. if you had your 4.3.3..
If you previously unlocked your iphone 3g or 3gs, chances are you are on the 6.15.00 baseband. this baseband is also known as the ipad baseband and many users have reported inconsistent gps signal. follow the step-by-step video below to get your baseband downgraded to a more stable, unlockable, version.. Iphone 3g custom fw with baseband 6.15. file name: iphone1,2_4.2.1_8c148_custom_restore.ipsw file size: 330.98 mb dont forget to press thanks no problem to restore this custom firmware even if i had tried before official upgrade to 4.2.1 ( iphone 3g ) ? of course i don
