I should have eluded to my point properly, please excuse me. My theory as to these cases of bricking, was that some bug in the software caused hardware failure, it was the only explanation the other techs and I could come to.
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Will upgrading to 4.0.1 hinder my ability to JB my iPhone 4 in the future?
- Thread starter OrlandoTragic
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I should have eluded to my point properly, please excuse me. My theory as to these cases of bricking, was that some bug in the software caused hardware failure, it was the only explanation the other techs and I could come to.
Total BS. If the phone could not be put in DFU mode, it had a preexisting hardware failure that had nothing to do with 4.0.1. Nothing in 4.0.1 could possibly cause that kind of hardware failure. Please stop spreading this nonsense.
Like disconnecting the cable right in the middle of the re-flash?
Even that could not prevent DFU. DFU is hard coded into the system chip and cannot be flashed by an upgrade.
This may be true but lets say the firmware was right in the middle of re-flashing the modem firmware and you interrupted it. I am not convinced that the hardware DFU is totally immune to software corruption. I also admit not to be an expert so who knows....
I do admit it is completely possible (and probable) that it was due to pre-existing hardware issues, but the reason I didn't look at it that way was the fact that we had 3 of them in the same day, all after updates to 4.0.1. Although it is completely possible these are isolated incidents caused by pre-existing conditions with the phone. We get a write up about the phones to give to customers when something like this happens (when a phone can't be fixed in store) so I'll check that write up after one gets done.
DFU and modem firmware are completely separate. Interrupting the flashing of the SGold processor can indeed brick the SGold processor. That will prevent you from using the iPhone as a phone, but even that cannot brick the phone. It will still be possible to put the phone in DFU mode.
The code for invoking DFU mode is the very first code executed on the iPhone. It is run from the VROM and is copied directly from the ROM. Since the ROM of the S5L8900, S5L8720 and S5L8920 cannot be flashed, it is simply not possible to corrupt it.
In other words, DFU mode within itself cannot be corrupted but the interruption / corruption of a components firmware can be, resulting in an inoperable phone.
Technically yes, although I really can't stress enough how much I recommend just sitting this one out, at least for the time being. But it is ultimately your choice.
I wish you would not put words in my mouth. I meant exactly what I said: it is possible to brick the SGold processor, but not to brick the iPhone.
Narimonk:
This may just be a coincidence but it seems as if my proximity sensor is a little more sensitive on 4.0.1 It turns off the display just a little more soon as the phone approaches my ear.
Could be subjective but I have yet to have a problem with it after the update.
I don't think you and I are looking at this on the same page. The point I am trying to make is that the interruption of a firmwares installation is possible to cause hardware failure and hence make it nonoperational. There is a fundamental relationship between hardware and software to which neither will operate correctly without the other. This is all I am saying. Whether someone will define this condition as bricked or not is subjective.
You are talking about something entirely different than bricking the iPhone, though. The fact remains that it is fundamentally impossible for any software installed on the iPhone or flashed by iTunes to prevent the iPhone from being restored to a bootable state by putting it in DFU mode and restoring to the latest firmware. Thus, it is absolutely impossible to brick the iPhone, narimonk's claims and your doubts notwithstanding.
No i only have the 4.0 SHSH saved...so im pretty much SOL until Comex releases something..
I just upgraded/downgraded my iPhone 4 from 4.0.1 to 4.0 a couple of times trying to prove a point.
For now I didn't need it, but I have my SHSH on file and was able to complete the upgrade/downgrade process at least three times without ill effect. It even still had the custom iPhone app I was working on in Xcode earlier in all the restores.
For now I didn't need it, but I have my SHSH on file and was able to complete the upgrade/downgrade process at least three times without ill effect. It even still had the custom iPhone app I was working on in Xcode earlier in all the restores.
Sailboat On Land .... or s*** out of luck
or it's a guys name... Im 95% sure you were joking about this anyways.
YES PLEASE! I hate the new signal layout. I like the signal bars as they are, LINEAR.
I am also so detail concisous that one of my reasons to jailbreak is to get back the old Pre 2.1.0 3G, EDGE and GPRS icons. I love those.