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1 iPhone 3G shuts down when locked, what do I repair?
My 3G will shut off when it goes into lock mode. This does not occur when it is plugged in. The power button is also unresponsive whether plugged in or not.
I have already taken it completely apart and made my best attempt to clean everything with isopropyl, even the underside of the power toggle.
When this problem first came up I also noticed that upon every single reboot (which only happens after I plug it in), the battery would be in the red zone, and would require charging time to reach green again. Due to this, I ordered and have already replaced the battery, many thanks to ifixit and the guides provided. Since then I have not seen a depleted battery upon reboot, great, one problem out of the way. On to the next.
I was condsidering replacing the headphone jack assembly, assuming my power button was un-salvageable. The only thing staying my hand is the $50 price tag for the part and no guarantee that this will also fix my shut down problem when the phone locks. The headphone jack, mute toggle, and volume buttons are operational, it is only my power/lock button that will not respond.
The 3G will wake up when locked if it is plugged in by use of the home key, but if I let it lock unplugged I must plug it back in so that it reboots to turn on again.
I have completed several facory resets while praying to the technology gods, but alas, to no avail.
#1: Depleted battery upon every reboot (FIXED)
#2: Unresponsive power button.
#3: Shuts down upon locking when unplugged.
Does anyone have any suggestions for me? Does anyone think replacing the headphone jack assembly may fix the shut down problem as well? Is there a finicky way that I may have foregone to clean and reassemble the power button? Have I lost my first iphone to the ravages of time (over 3 years old) and a humid climate?
Is this a good question?
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5 Comments
*Had not considered power ic. Thank you for the suggestion. I will try the flex first, and will have to get back on here once I have recieved and installed it.
by jaisoun
*After considering the power ic comment I decided to open up and try re-mounting my power button and flex cable. It turns out it is finicky, and can sometimes take several tries before the right contact is made. My power button functions once more after the cleaning and several assembly attempts and testing. I believe the power ic replacement may be beyond my skills, not to mention a more expensive part to replace. If I am junking this phone, I will try it once if I can find an inexpensive one.
On a quick note, since my power button is working again, if I set my auto-lock feature to "never" I can unplug the phone and manually lock it with the power button. The phone will be able to unlock up until ~12 seconds of being locked, after which it shuts off. Does this still sound like a power ic problem?
by jaisoun
I tried to upload a copy of the pins of the power management chip but I'm an idiot at it! it is responsible for the sleep/wake function, but there are a few fuses on the path too.. I'd like to hope it isn't that, have you tried a DFU restore? make sure your phone is backed up, this may help..There are plenty of people advertising that they replace these parts on ebay shops so try there.
by pollytintop
*Update* I have installed a new flex cable with disapointing results. The phone is still being fussy about when it locks and unlocks using the power button and will not reboot when holding the power button. Aside from the power ic suggestion, I can think of no other repairs I can manage easily. Thank you for your time. On a brighter note, I now own a fancy backlit coaster that plays music.
by jaisoun
Don't know if anyone is still checking this thread. I have a similar problem with an old 3G trying to bring back to life. If I turn off autolock, phone will stay on forever. Also if it's plugged in, locked or not, stays on indefinitely. But after about 20 seconds of being locked, turns itself off. Touching home or power button boots it back into apple logo. Tried a new battery and nothing changed. Restored to no avail. Looking for any ideas. I see the power IC suggested. Anybody try that?
by Ben Spratt