ho to downgrade 3gs w/o shsh
 

i have 3 iphone 3gs in 4.0.2 can't downgrade to any version

need any solution

bro

choklat

not work Downgrade method.. i Downgrade some phone butt last 4 days not work downgrade method....

if ur shsh save to cydia then it can be possible.otherwise no chance

no solution for now just wait and dont do anything with your phone like downgrade u waist your important time:p

very simple rule...with regards to all iphone...
NO saved shsh blobs no DOWNGRADE..
UPGRADED to 4.1...no matter if you have saved shsh blobs..cannot Jailbreak/unlocked
CHEEERS!!

sorry my bad not all iphone LOL
3G can downgrade w/out shsh blobs before 4.0
Sorry my Bad..CHEEERS

can if one give me pinout of jtag baseband iphone????

this is interesting realy !
nobody talk about jtag for iphone 3gs,4 ?
does ORT support it?
any confirm
http://img218.imageshack.us/img218/149/baseband.jpg
any info plz share it :confused:

one more,

http://oi55.tinypic.com/2s1oyeb.jpg

WONDERFULL !!!!!!!!!!!!!!!!!!!!

Do you have got more ??????

but ...
i think JTAG for iphone is very powerfull tool .. so there is the same platform cpu like HTC ..

iphone 3gs 4.0.2 downgrade to 4.0.1 without backup of shsh
 

just done 2 iphones both 3gs,both had been upgraded to v4.0.2
there was no previous jailbreak for these,so no backup of shsh.
this is very easy way to downgrade v4.0.2 to v4.0.1
you need latest itunes,get that from apple.
the v4.0.1 firmware:
Code:
http://www.iphone-hacks.com/download...6_Restore.ipsw
tinyumbrella get this from:
Code:
The Firmware Umbrella
we 1st need our shsh this is how its done.
edit your hosts file
i put
C:\Windows\system32\drivers\etc\hosts edit in notepad
add these 2 lines

127.0.0.1 gs.apple.com
74.208.105.171 gs.apple.com

click saveas,and save as hosts,
(vista and win7 users,need to right click notepad,and select "run as administrator")

start itunes,leave running,and ignore it for now.start tinyumbrella,(again if you using vista or win7 then right click "tinyumbrella" and select "run as adminastrator")
then plug in iphone.
tinyumbrella see iphone, +say its v4.0.2 if you tick the advanced
in the middle selectable field select "3gs iphone v4.0.1"
thats the trick,,,,,
click start TSS server
then save my shsh
it report saved ok,

now leave tinyumbrella tss server running,(in background)
disconnect iphone,click to bring itunes into view,
get iphone into DFU mode,/recovery mode,
if successful,it show black screen,plug it to computer,itunes see it in recovery mode,itunes ask you to restore.
hold down "shift" as you click "restore"
window pop up,point it to ur 4.0.1 firmware(the firmware you downloaded earlier).
if you doing 3gs iphone then its called
iPhone2,1_4.0.1_8A306_Restore.ipsw

sit back and let itunes do the rest,,,
then once done,post result plz

Still Working THanks

we cant downgrade iPhone 3Gs Because its need server signature then it restore/update on latest version and apple always disable it when new version launched so we cant downgrade it.
shsh only can keep us on present baseband on update/restore nothing els
i mean if you saved your shsh file then shaurk server you can update iPhone without updating base band

WBR

What do you need that for?
See also this:
Baseband JTAG - The iPhone Wiki

All these infos are probably for iPhone 3G or older.
The Apple drawing above looks like from a matrix printer (very old).