Story of an Un-Bricked 3GS

[harisalavi]

Well I just bought off a iPhone 3GS from a friend and with high expectations (such that one would expect from a person finally owning their first Apple product), I browsed it till I got tired. Seemingly unsatisfied with my currently jailbroken and unlocked firmware (iOS 3.1.2), I searched online for an easy guide to update my phone to the iOS 4.0 for its cool look and fixes. At this moment my iPhone had the following specifications

Firmware: 3.2.1
Jailbroken: Yes
Unlocked: Yes
Condition: Tethered
Bootrom: New
Baseband: 5.11.7
SHSH: 4.2.1

Ideally, this condition didn’t need any updation expect for an un-tethered jailbreak which would only have taken a few seconds to do. Had I been any wiser, I wouldn’t have done anything with my phone since I could have gotten cool looks using Cydia applications. Anyhow, I proceeded to an update using Snowbreeze, but midway I found that this software is not capable to update the newer versions of 3GS (new bootrom). So I searched and found another method that required Redsnow software. First I downloaded a custom ipsw (firmware) from a website for iOS 4.0 and restored the phone in DFU mode using iTunes pressing the shift button so that I could use my custom FW. (Mistake 1: Downloaded an un-verified firmware) (Mistake 2: Restored with a non-pwned DFU mode). The installation was completed but the phone never rebooted and stayed in DFU mode. Thinking of this as a normal thing, I proceeded to use Redsnow to jailbreak my device. The software asked me for the current stock FW however that couldn’t be loaded properly, so I used an iOS 4.1 firmware. (Mistake 3: I chose the wrong firmware). I chose the install Cydia option. The phone started, some text rolled and suddenly the phone shut down and stayed shut. It had gone back into a DFU state. Sensing trouble, I re-used Redsnow, this time with boot-tethered option. To my surprise the phone came back on but now it was asking me an activation SIM which is not available/supported in my country. Also as soon as I would take my phone out of the computer, it would again go in DFU state. Finding no solution online and being too tense to try more antics myself, I took it to an expert. The ‘expert’ was none the wiser yet tried several things. Finally, saying that restoring it to the latest firmware (iOS 4.2.1) is the only option to save my phone, he plugged it in and tried it through iTunes. This resulted in an Error 28 which according to the expert meant my phone’s hardware had failed and there was nothing more possible.

In shock and dismay I took my phone back and searched online for this error 28. To my further dismay, most online queries resulted in the same result. However, some responses mentioned that I must drain my battery or open my phone and disconnect the battery so that temporary memory is cleaned. Seeing this as the only possibility remaining, I left my phone alone for 5 days to let the battery drain even though I knew that 3 days would have been enough. In these 5 days, I read alot and found what I needed to do. The specification of my phone at this stage was

Firmware: 4.0
Jailbroken: No
Unlocked: No
Condition: None
Bootrom: New
Baseband: 5.13.4
SHSH: 4.2.1

I had found out by now that I could only properly update to 4.2.1 because I had SHSH saved for this firmware only. So I connected my phone, used Redsnow with 4.0 FW and choose ‘put phone in pwned DFU mode’. Even though my phone was already in DFU mode, a custom restore requires a pwned DFU mode. With pwned DFU, I opened iTunes and restored the phone with a verified custom 4.2.1 FW. A custom FW allows the old baseband to be maintained and has the option to activate the phone without original SIM. So now the phone rebooted but this time it went to recovery mode (iTunes logo). Seeing progress, I opened Redsnow again, this time chose a stock 4.2.1 FW and choose the option of Install Cydia. With that done, phone was rebooted but now the phone got stuck at the Apple Logo with the loading circle stopped in it. This is normal as far as I know. So then I used Redsnow again and chose the boot-tethered option now. The phone was rebooted and now it started to the home screen. I browsed around but to my surprise there weren’t any signal/network. My phone was network locked still. I turned on Wi-Fi, opened the Cydia application and chose the Ultra Snow package and installed it. And viola, the phone had signals now.

With this done, my phone has now the following specifications:
Firmware: 4.2.1
Jailbroken: Yes
Unlocked: Yes
Condition: Tethered
Bootrom: New
Baseband: 5.13.4
SHSH: 4.2.1

There hasn’t been any un-tethered jailbreak for iOS 4.2.1 so everytime my phone reboots, I have to use Redsnow and choose the ‘boot tethered’ option. However, this whole process made me more knowledgeable and brought my phone back to life.

[i.Annie]

Just FYI you don't need SHSHs to restore to 4.2.1, Apple is still signing it. You'd need SHSHs to go to 4.1 and below because those aren't being signed anymore.