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A Shower Of Thoughts

Issues with HDMI, Apple's USB-C dongle, and my MacBook Pro.

Published on .

I was having issues with my MacBook Pro (13-inch, 2017, Two Thunderbolt 3 ports) when trying to connect my external screen with its HDMI cable via Apple's USB-C Digital AV Multiport Adapter a.k.a. dongle.

Basically, the MacBook wouldn't recognize the HDMI connection via the dongle, no matter which of the 2 ports I was using. Sometimes, not even the power charging would work, neither directly to the MacBook nor via the dongle.

I tried with another dongle of the same kind, and it didn't work either. And both dongles worked fine on another, similar MacBook model. It didn't seem to be a dongle issue.

This seem to indicate it was an issue with my MacBook itself. It could a hardware-software issue.

After DuckDuckGoing for driver-related issues, I found this Apple Support Page about resetting the System Management Controller. It provided the solution to my problem.

Solution #

Resetting the controller that handles the management of the USB-C connection a.k.a System Management Controller (SMC) fixed my issue.

These are the steps I took for my MacBook Pro (extracted and paraphrased from the article linked above. Might be different steps depending on your specific MacBook model):

  1. Shut down the MacBook.
  2. When it's off, press and hold the left-side control + option + shift keys.
  3. While holding those keys pressed, press and hold the power key (on the upper right corner of the keyboard) to turn the MacBook back on.
  4. Keep those 4 keys pressed for 10 seconds.
  5. After those 10 seconds, release all the keys. The MacBook should bootup like usual, and the problem should be solved. It was at least for me.

Afterwards, both the HDMI connection and the power charging worked fine again, all from one dongle.

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