Is this possible:
I have two USB-C ports on my MacBook Pro 2019. One port works perfectly well. The other is odd to say the least.
After some testing, it seems as if the port "can't handle strenuous tasks" and by strenuous tasks, I mean running a USB-C hub with external hard drives plugged in it or using the port to go to an external monitor.
It does work when charging my iPhone or using the port to charge the MacBook itself.
So my assumption overall is that it does work, but only small, less strenuous tasks, if that's even possbile?
Can any USB-C knowledgeable people confirm this is possible? Could it be a software issue?
I've tried resetting stuff like the SMC etc. just haven't reinstalled macOS yet, which is the last thing I'd wanna do, it's on the latest version of Catalina at the moment.
Best Answer
You have a hardware issue.
And, unfortunately, it's a logic board problem.
Unfortunately, without putting hands on with proper diagnostic gear it's impossible to know. In fact, if you take it to Apple, they will simply change out the logic board rather than identify and fix the problem.
The one thing you should do is an reset the SMC. There are different methods depending on your Mac model so be sure to read the steps carefully.
This is one of the actual few problems where an SMC reset is applicable - you're having power issues. Re-installing macOS is the last thing you should do - booting into Safe Mode or Recovery will get you a clean version of macOS without the hassle of overwriting your system and risking your data. You can also run Apple Diagnostics to see if there are any error codes.
Potential Workaround
If you can still transfer data, just not handle the "strenuous" tasks as you described, you may still be able to work with it if you use a powered USB hub. It will supply the power to the USB bus that your logic board can't