Problem charging my iphone using the cigarette lighter

[Gary2412]

Hi, can anyone shed any light onto this problem? It doesn't make sense to me.
I have checked my cigarette lighter with a multimeter and i have 12v. I proved it worked by trying the actual lighter itself, so i know it has current too.
But when i plug in a usb device and the iphone cable it will not charge my phone.
I have checked the usb device, it is giving me 5v. I can charge my colleagues Samsung but it wont work on my iphone. It's totally bizzare!
I've tried several cables, they all work when i plug them into any other usb port.
Has anyone experienced this? I'm at a loss what i can try next.
This is on my C6 2006 A6 Allroader

 

[Andy101]

Gary, you may get a better response by posting this in the C6 forum.

 

[Gary2412]

Oops, oh yeah, didn't notice that. Thanks, i'll try it there,