IPhone charge USB iMac error

[DKCHD]

So far we have charged two iPhones via the USB ports on the family iMac (2014) - also in sleep-mode. Suddenly this is not an option - it starts but quickly disconnects. Any thoughts?

 

[havokalien]

cable has degraded? end has crud on it? Try another usb port? its bi directional, turn it either way. Also sometimes the phones or the mac can have issues and both being restarted will get rid of glitches.

 

[maflynn]

Try a different cable, and different computer (or wall adapter) to narrow down what the issue is, i.e., cable or computer.