3gs will not charge/connect to computer

When I plug my 3gs into a computer, nothing happens. I've tried on my old powerbook as well as pc's at home and at work with the same results.

I have checked all of the usb ports using other devices and all are powered and working fine.

I have tried multiple phone chords on wall and car chargers, all seem to be working fine.

The phone does charge on wall and car chargers.

If the phone is off and i plug it in, it will turn on, but that is all that will happen.


I have tried restarting the phone and computers. I've reinstalled itunes. I've tried almost all the advice i could find anywhere online.

any ideas?