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I just got a used MacBook Pro, 2017 without the Touchbar. It has 2 USB-C Ports on the side. I'm not using mobile much, but I do sometimes. At my desk I'm using a USB-C device that gives me an HDMI, USB-A, and USB-C port for charging.

I've noticed that while everything is plugged in and the laptop is on everything seems to work fine. However, if the laptop is asleep the system stops charging. It only seems to charge asleep when the charger is directly connected to the computer. I've reset the SMC twice and the NVRAM and this is a fresh copy of macOS installed via Internet Recovery.

Is this normal behavior?

I'm concerned because I bought the laptop used from a computer shop and I have a limited window to bring it back to them if it is faulty. I just don't know if this is normal or not.

I'm assuming that macOS requires to be running for it to recognize the splitter device. I've got an external hard disk attached to a powered USB hub which is then attached to the laptop via this splitter device. When the computer wakes from sleep I get an error saying I should unmount the device before powering off the drive. I never got this error with previous Mac's that had their own USB-A ports.

In addition to the USB hub and charger, I also have an external monitor connected via the HDMI port, so all 3 are going through this one splitter device. I don't know if that is relevant, but I thought I'd include it in case it is. Everything seems to work perfectly when the system is on.

I really like the idea of when I want to do work with the larger monitor and such I can just plug one thing in, so I would really appreciate help on seeing if I can get it working in this configuration / if this is NOT normal (i.e. there is some potential hardware failure) returning it to the store I bought it from in short order.

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  • Just to add information which points to Allen having the right of it, there is a strange behavior as well where the computer is unplugged for a while. After I go to plug it back in, I have to unplug the power from the splitter and plug it back in to get the laptop to start charging. Definitely believe it is the splitter and I have a new one on order. Apr 23, 2020 at 6:26

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However, if the laptop is asleep the system stops charging. It only seems to charge asleep when the charger is directly connected to the computer.

You've narrowed down the problem to the "splitter."

If it charges when directly connected, but not when going through the splitter, your MacBook is not the cause of the problem. If you were to bring it into any Apple store or repair shop, the first thing they would do is hook up a known good working charger to your MBP. If it charges while sleeping, you'd be told that your MBP is working correctly; which it is.

What to do?

That vintage MacBook Pro has two Thunderbolt 3 ports so...

  • Return the "splitter."
  • Try not to use HDMI (it's very flaky, IMO). Use DisplayPort instead. Thunderbolt 3 natively outputs DP; it will have to convert the signals to give you HDMI.
  • Use a "proper" (meaning an active adapter) USB-C Hub with Power Delivery and 4K support if you must use HDMI.
  • Because you only have 2 TB ports, I would spring for a Thunderbolt 3 dock instead. This way you'll have ample room for growth should you want a second monitor or additional USB ports.

(Standard disclaimer follows)

Of course, if you're not comfortable that your MacBook Pro doesn't charge with the splitter you've chosen, by all means, return the Mac. If your splitter continues to exhibit the same behavior, you'll have proof positive that the splitter is the issue.

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  • Thanks, I appreciate that you point out 3 different products which may be of use. This still does not answer my actual question (is this normal behavior). Though the additional information you provided in your linked answers is helpful, I agree that USB-C and Thunderbolt 3 are confusing. I have the monitor I have and I would really rather not spend more money on a new monitor to use DP, though that sounds like a nice idea I don't have a few hundred bucks laying around. I will keep that very nice $50 hub and $300 dock in mind but my upgrade budget is tapped after being this laptop itself. Apr 22, 2020 at 16:30
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    It's not normal behavior because the problem is your splitter.
    – Allan
    Apr 22, 2020 at 16:37
  • I'm not marking this as solved until I can try a different device on it. I am still not sure, since it does charge when the computer is on. I read on the Apple Support forums that several people for 2016 and 2017 Mac's had a similar issue. As soon as I buy a different USB-C Hub, I will try it and update this question. Apr 22, 2020 at 16:41
  • I was really floored originally by the idea that a $50 hub would be needed. In fact, I was able to purchase a $30 hub which has solved the problem. However, I think I should have taken the advise as presented because the less expensive device VAVA USB C Hub, 7-in-1 USB C Adapter seems to not be entirely compatible with my Logitech Universal Receiver. Everything else works. Thank you. Apr 25, 2020 at 22:55

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