iOS4 update - now iPhone now reboots during phone call (continued)

Will this work with 4.3 upgraded 3GS? Will I be able to install further iOS versions, if released? And where can I get mobilewatchdog file from
Thanks

In the interest of this thread, and even more so the folk experiencing reboot during call issues with their 3GS, I want to reiterate information that I've shared in recent days.

I have been contacted by a number of fellow 3GS owners who wanted to know how I addressed the issues I was experiencing. With the information provided, those that have been able to invest a little time have reported back that they have a working iPhone again (although it has not worked for a couple of people, who I suspect have secondary issues running in tandem).

As stated before, I cannot take credit for the fix but I'm happy to share my experiences and help others. If you're running iOS 4.2.1 and are happy to spend a little time working with your iPhone 'technically' then email me directly (you can find my email address in my profile).

Jonty.

I have the same problem after upgrading my 3GS to IOS4.x. 3-5 minutes in a call, the iPhone reboots. I have tried to reset/restore the iPhone - but didn't help.
I have tried to find a way to downgrade to IOS3.1.3 but haven't found a way to do it. It would be realy helpful if Apple re-released IOS3.1.3 to all the 3GS users. Otherwise I have to trash the 3GS and by a HTC or Nokia. I will not by an Apple product again when Apple don't admit they have a problem and help there contumers....

the same problem here... reboots during call after 5 minutes

Iphone 3Gs (16GB), iOS 4.3, no modifications except update iOS, Provider: German Telekom

I have tried all 4.x version and still same problem. Reboots during call after 3-5 minutes.

I had the same problem with my 3GS and sent it back to T-Mobile provider. They gave me a new iPhone (replacement), also a 3GS.
Now I can do phone calls longer than 5 minutes and it seems the new iPhone does not have the problem although it uses the same iOS (4.2.1). To me it seems it must be a problem with the hardware.

With iOS 4.3.1 the reboot is still there. Why can't Apple fix this and why don't they respond

Confirm too, it reboot also.

For the regular readers: here is my update.

After handing over the phone to my dealer 5 weeks ago, he called me that my iPhone 3GS has been replaced with a brand new one! Reason unknown, but I am happy.
It came with 4.2.1 installed and just made a couple of calls without any problem.

So, I hope I don't have to post here anymore and hope for you that the final fix is released soon.

An extremely favourable update on my part, in the interest of others and this thread.

In recent weeks I've been contacted by 50 (fifty) 3GS owners, each of which I've been more than happy to email fix details regarding this ridiculous problem. All bar a few have been able to engineer themselves a working iPhone again -- which is excellent! Unfortunately for two people problems remain, but I suspect secondary issues.

I'm conscious that I'm repeating myself to a degree but in the interest of folk experiencing reboots during calls I want to reiterate information that I've shared previously.

I have now been contacted by a large number of 3GS owners who wanted to know how I addressed the issues I was experiencing. With the details provided, the majority that have been able to invest a little time have reported back that they have a working iPhone again! I cannot take credit for the fix but I'm happy to share my experiences. If you're running iOS 4.2.1 and are happy to spend a little time working with your iPhone 'technically' then email me (you can find my email address in my profile).

Jonty.

Problem fixed.
After replacing the battery with a new one, the iPhone have not rebooted during call for several days now.
Still i think Apple have a problem with their power management in 3Gs. It seems like the IOS4 have a higher load on the power system because of higher CPU load and maybe also higher load from GSM transmitter and WiFi. I think what is happening when the 3Gs reboots is that the battery (little over 1 year old) can’t hold the minimum voltage for the system during power spikes. The result is a system crash and then a reboot.
The new battery is stronger due to lower internal resistance and because of that it can deliver higher current without dropping the voltage below the minimum limit.

FIX for iphone reboots during a phone call after upgrading 3gs ios to 4.3.1.

Just want to give my testimony.

My Iphone 3gs running ios3? no problems, upgraded to 4.3.1, then the dreaded reboot after 4 minutes, did a lot of reading and decided the only logical was to change the battery or revert back to ios 3 if possible, anyway, brought a battery and little tool kit of ebay - about £10, watched a utube video and took the plunge, FIXED, now it doesn't reboot itself anymore, although it was kind of handy when i was speaking to the mother-in-law 🙂

I did read one person did just disconnect and reconnect the existing battery, that might do it for a short while, but at these prices you may as well treat yourself.
It didn't wipe any data from the phone, just the date and time needed resetting although I had a backup that I took before I changed the battery.
It for some reason lost some certificates to things like imap.google.com for some of my email accounts, so just accepted the new ones and all was fine. Because the date was reset to 1970, I had a load of reminders pop up as soon as I put the date and time correctly. I found the compass needed resetting and some of my GPS apps like tomtom took about 8 minutes to find its location and the standard maps package took about the same to finally pinpoint my location. Apart from that everything else seems okay. With the right tools (including a suction cap to help remove the touch screen) it was really easy to change the battery.
Hope this helps others and good luck
Andy

Hi, I have been having the same issues with calls longer than 5 minutes crashing the iPhone 3GS since iOS 4. Earlier advice from th thread, to do 3 things; lock into portrait mode, turn off mms messages and turn of notifications may have worked, I just made a 30 minute phone call!

However an earlier post indicates the issue is caused when the signal is low, and during this call I had full signal, so its inconclusive whether the workaround really fixes the issue.

The recent posts regarding fixes related to replacement batteries is very reassuring -- and re-affirms my own belief that the reboot issues pertain to one of two problems. This is based on my own experiences and feedback I've received from others -- as well as the replies on this forum.

Primarily there is a software issue which sees iOS 4.x incompatible with the logic/circuitry in a number of batteries. Secondly, some batteries either have a logical or physical issue which requires them to be replaced (although seems to be less common). If you're really unlucky (and I know of a couple of people) you may have BOTH problems!

But ending on a positive note, it's comforting that there now appears to be a couple of lifelines for all. The no-cost software fix is always worth a shot first followed by the not-so-expensive battery change (albeit with a slightly fiddly procedure). Great news for us but shame on you Apple.

Jonty.

Hello,

this fix works fine:

http://xsellize.com/topic/98630-iphone-3gs-32gb-factory-unlocked-reboots-5-7mins -on-call-probable-fix/

If tested it on my 3GS 16GB running on IOS 4.3.1