It's related to iPhone power requirements and USB port power capacity. It's clear the iPhone needs its good power quota from the USB port for charging. If the USB port it's connected to doesn't meet its power requirements, this disconnection issue could arise. It's quite understandable. If minimum current is not delivered, voltage will drop a bit and that would affect the connection, resulting in the phone getting disconnected.
USB ports should have enough power for the iPhone. Apple would not sell millions of devices that could not charge and connect with the port they say it should. So I think the issue is related mainly to power supply quality. USB ports feed from the 5V rail. If that rail is not powerful enough to satisfy every device sucking power from it, it will drop. Right now, my system shows 4.68V on the 5V rail. Ok, internal mobo voltage meters are not extremely precise, but they do the job showing that real voltage is below the 5V mark. So replacing my power supply unit should do the trick.
Another solution is buying a self-powered USB hub. This hubs offer USB ports fed using it's own power supply, so any demanding device should not affect system power supply, therefore not showing any issue.
A last resource could be a USB Y-cable. I've seen one of these on a website a couple of days ago. They have two male connectors on one end and one female on the other. You then plug both males in two USB ports at your computer, having twice the power of a single USB port, allowing the iPhone to have it's needed drink of power. However, if 5V rail is low, no matter how many ports you join for more juice, the signals will have problem since they are interpreted by voltage rather than current.
My two cents.
You'll never sync with a cable again. It's super.
Then I tried connecting my iPhone to a USB hub with 5 USB ports connected to my Macbook.. It then worked without a glitch :) Thank you Meneidur for the idea :)
Actually there was problem with incorrect iPhone data cable, if you are not using original cable which came with iPhone then it will work for you too, because there is available iPhone cables in market those are not compatible with iPhone 4 or 4S, I had data cable and there were 4 pins inside of 30 pins connector and when I connected 5 pins inside of 30 pins connector my iPhone is working perfect
Correct pins configuration is hereunder
Hope it will work for you
I have suffered this problem. What it was NOT was USB connections, outdated software etc. Ok, try all these, but you will find that it is a built in problem with the iPhone.
I bought new lead and upgraded software etc (& spent 20 hours doing this) no joy
What solved it for me.
1) put the phone in airplane mode
2) disable bluetooth
3) Disable all apps that try to sync (e.g. dropbox, photos)
My phone then managed to stay connected for enough time to update
4) spend an hour re enabling all the apps and settings.
It works, but is incredibly annoying, syncing my iPhone is now a 2 hour tedious job, not plug & play:(
Apparently it has something to do with power dropping when apps are active
- Courtney, 5 years ago
- Nick, 5 years ago