Can USB cables have ground loop issues?

**Will Albers** · 09-27-2005, 03:10 PM

In the front of my vehicle, i run a Carnetix 1280 for 12v to my screen and 5 v to a USB hub. In the rear I run an invertor. I'm having issues where the hubs will not work when plugged into the front end of the USB ext cable (basically in the front of the car, while the PC is in the rear).

Will the fact that the 5v coming from the front isolated supply (powering the hub) is seperate from that of the USB 5v (pc power supply), cause issue?

**numbers** · 09-28-2005, 01:08 PM

No. That would not cause a problem. Do other things work when plugged into that usb extension? Does the hub work if plugged directly into the computer? How long is the extension?

**Will Albers** · 09-28-2005, 03:09 PM

Its weird... Individual items work fine when plugged into the cable, yet hubs will not work at the end.

Hubs will work at the PC but even then, some components (like my flash drive) will not work off of the hubs.

Flash drives will work when plugged directly into the PC.

Today i will put a PCI USB card in and see if it helps. Im at a loss