Macbook Pro USB port won't work

Unfortunately, your USB port has died

You've done more than enough tests to diagnose the problem and unfortunately this one is hardware related, not software or firmware. There's no NVRAM setting or SMC control that handles power to the USB (directly).

The "light" that you are seeing on your USB device doesn't mean it's connected and recognized by the computer. It simply means it is receiving power on the +5V pin of the USB port.

Looking at the pinouts of a USB 2.0 Port, we can see that there is a dedicated +5V for power (why your phone charges) and two pins for Data (Data+/- for positive/negative voltage signals) and a ground. Data isn't being transmitted (which is why your iTunes doesn't recognize your phone).

What could the problem be?

• It could be a failed USB controller (SMSC USB25138)
• Broken or corroded solder pads/joints on the USB ports or related components
• Physically broken USB port

Any/all of these would contribute to the weird behavior you are seeing.

From iFixit.com, we can see that the board layout as follows:

The good news is that this can be fixed. It's not a DIY type of repair, but there are shops that specialize in component level repairs. Just do a search for "MacBook Logic board repair" (Rossman in NYC is really good - not affiliated, just a happy happy client)

Since you indicated it was only one USB port, the chances are good it's just a bad connection with the physical port itself. An immediate fix would be to purchase a USB Hub (powered preferably) so you can get your connectivity back.