HDMI Monitor detected but no display

I have a 2017 Mac Book Pro connected to a usb-c docking station. My LG Monitor, 25UM57-P, will not show anything on the LG screen when connected through the dock. I have a second portable dock from BanditToBlue, which, using the same monitor, same HDMI cable, will display without issue.

Added note: I have the exact same dock at my office, so I know it is not a software issue

Hello Sid, thanks for posting! Just to clarify, you are using one of our UD-3900 docks with your 2017 MacBook Pro and the LG monitor connected to the HDMI cable is not displaying?

Would you be able to clarify how you are connecting the dock to your MacBook Pro? Are you using a separate USB-C to USB-A adapter?

Also, you mention you have another dock at your office. Does the same behavior occur with your MacBook Pro or is the UD-3900 dock at your office working with your MacBook Pro?

Please let us know this additional information at your convenience and we will proceed accordingly.

Thank you,

David W.
Plugable Technologies
www.plugable.com/support

I have a UD-3900 at home and at the office, the HDMI ports on my UD-3900 at home do not work. Connect to both docks via the USB-C cable that came with the docking station.

My point in mentioning the “portable dock”, i.e. the BanditToBlue device that I’m currently using at home, is to note that there is nothing wrong with the LG monitor or the HDMI cable I’m using at home as I can get an image perfectly fine through that dock.

I use the same doc with a secondary monitor connect at the office and all works well - this lets me know that software/drivers are not likely to be the cause - what it appears to be is that my UD-3900 dock at home has gone bad.

Hi Sid, thanks for the reply and I would agree that it seems that the dock you have at home is defective since the one at your office works well. We’d be happy to assist with the replacement process and I will reach out to your email address used to register on our forums to facilitate this process.

Thank you,

David W.
Plugable Technologies
www.plugable.com/support