USB Port on MacBook Pro is Misbehaving

[QueHuong]

This post has 2 questions in one, hoping someone could shed some light on it.

I've been having problems with my 2014 MBP whose left USB 3.0 port is acting sporadically. One day I plugged in my iPhone to charge it when the phone cycled between being charged and not, as if I was repeatedly plugging in my phone to the USB port and unplugging it. And when I plug in the USB receiver for my mouse, the mouse skips. Is there a diagnosis for this problem?

The other USB port is fine. Whenever I transfer data between an external HD, I always use the good USB port for fear of data loss if using the bad one. Now I need to transfer data between 2 external hard drives containing over 1TB of data. Because I don't want to risk data loss/corruption by plugging either drive into the bad USB, I was thinking of buying a powered USB hub, connect it to the one good port, then connect both HDs to the hub to transfer data between them. Are there any potential issues with doing this?

 

[postmortemIA]

looks like you still have a warranty. Why not ask Apple to take a look?

I have rBMP late 2013. I've used left side USB port, even with ext hard drives - never had a problem.

 

[ZGR]

Shine a flashlight in the faulty port to see if there is something obstructing some of the pins. Could be a super easy fix

Or not

 

[mfenn]

Shine a flashlight in the faulty port to see if there is something obstructing some of the pins. Could be a super easy fix

Or not

Agree. It sounds like something is causing an intermittent contact on that USB port. It could be as simple as the connector being dirty or it could be something like a cold solder joint which will require repair/replacement.

A 2014 unit should still be under warranty, so take it to an Apple store (or other repair center) to get fixed if you don't find or can't fix it with some simple cleaning.

 

[QueHuong]

Thanks for the inputs. Just some more updates in case that helps shed any light:

- I blew compressed air and that didn't help
- the issue is with any USB device plugged in: I tried different mice and the same issue cropped up
- I searched online a bit and some people suggested resetting the NVRAM or SMC which has worked for several people but that didn't work for me (http://support.apple.com/en-us/HT204063, http://support.apple.com/en-us/HT201295)
- the problem seems to occur when I plug another device into one of the ports on the same side as the USB. When the laptop is facing me, the USB on the left side is affected. It seems to be especially affected when I plugged an external monitor into the thunderbolt port or when I connected my NAS via an ethernet adapter to the thunderbolt port. My guess is that by delivering power to the thunderbolt ports, the USB port shows problem. The laptop is plugged in during this time.

I agree about bringing it to Apple but that will mean some downtime. I was hoping the issue can be solved before I bring it in. Thanks all.

 

[richaron]

I had a similar problem with a new laptop, although with mine the USB port was noticeably stiff plugging/unplugging stuff (due to contact with chassis).

I realised my problem was that USB 2.0 devices didn't make proper contact with 3.0 pins in the computer. There was no issue with USB 3.0 devices, so after complaining/returning/etc I just used that port for a USB 3.0 hub. Could your problem be similar?