Chosen Solution
I’ve got a 3GS running 4.2.1 and it’s about 1 year old. I’ve always had a Mophie Juice Pack on it, and would usually go through both the internal battery and the external in about 16 hours of pretty heavy use, as I would expect… Then 2 days ago the phone has decided to burn through the internal battery in about 90 minutes, and takes the external battery about the same time to deplete as well. The phone is always warm, and takes about 4 - 5 hours to charge back up. I’ve tried restarting, restoring, and removing all apps but the base ones - but nothing has helped. Is it possible for a battery to die from one day to the next (literally)? Should I replace the battery, or something more?
Sounds like a bad battery, you can get a new one here, and you can find a step-by-step guide here.
Same thing happened to my 3GS after I installed the OS 5.0 update. Now it just shuts down after 15 minutes of use off the charger even though it said 100% when I unplugged it and when it is back on the charger, comes right back up and says 91%, even though the phone turns itself off when that happens. So annoying!
i’ve got an old iphone 3g, os 4.2.1. check your sync configuration. i’ve not an internet plan, so i usually take advantage of free wifi connections. my iphon was configured to sync contacts and agenda with google, using “ms exchange” configuration. well, any change to contacts starts something consuming any available cpu power, drains battery and warmup iphone. removing sync of contacts resolved the issue. warning: this obviously removes contacts from iphone, so consider making a backup before proceeding.
Im having the same problem and have been the last 3 days. nothing different on the phone so will be taking it back to the shop saturday as the year is nearly up…. sorry u others are having problems too :( x Rachel
found it was an app designed for a later version of the iphone. Once it was removed, battery working OK
