2019 MacBook Pro can't recognize 2nd monitor

Purchased the TBT3-UDC1 Dock back in April 2021. Never set it up until today due to having another computer with its own dock and never got around to setting this up. Briefly got the 2nd monitor working but immediately stopped upon the next computer restart.

  • 2019 MacBook Pro with 4 Thunderbolt ports running Ventura 13.1.
  • USB-C connected from Thunderbolt 3 port on the dock to the Mac.
  • Both are Dell P2419H monitors connected with HDMI cables via DP-to-HDMI Active Adapters.
  • I can get one monitor working at a time independently but cannot get both going.

I understand due to the timeline, it’s probably out of warranty. Just wondering if you can help troubleshoot.

Thank you.

Hello Wynn,

Thank you for reaching out to Plugable Support!

I am sorry to hear that you are running into issues with your TBT3-UDC1, but I would be happy to help diagnose the issue here.

First, can you confirm that you are trying to connect to your laptop using the included Thunderbolt 3 cable that came with your dock? We’ve seen issues arise when a third party cable is used.

Next, some steps we’ll want to take are to perform a power-cycle of the unit to reset its internal hub chipset. We’ve seen that this can often restore the dock back to a working state when one or more of its functions are not quite working. To do this, please follow these steps:

  1. Disconnect all USB peripherals and displays connected to the dock
  2. Disconnect the docking station from host machine, then disconnect the power adapter from power
  3. Leave unplugged for 1 minute for power to dissipate
  4. Connect docking station initially into power only
  5. Connect docking station to host machine, then connect USB peripherals and displays, then test for functionality

Lastly, if the power cycle does not help, I’d like to perform an SMC and NVRAM reset of your MacBook. This may help your MacBook better recognize the dock.

To perform an SMC reset, follow the instructions here:

To perform an NVRAM reset, follow the instructions here:

Please let me know if this helps at all!

Thank you,

Plugable Technologies

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