Macbook Pro Mojave won't connect to HDMI projectors + monitors

I'm just trying to use the Apple usb-c to usb-c cable that came with the mba 2018 to connect it to the samsung usb-c monitor. Are you saying that the Apple usb-c cable doesn't support video over usb?

It seems like there's a compatibility issue or an issue with either the:

• Samsung monitor's usb-c port
• the Apple usb-c cable
• the mba 2018 usb-c port, or
• the Mojave display settings

All are brand new so taking the mba and usb-c cable to apple to see if they can isolate the issue

Researched usb-c and bought a Belkin usb-c to usb-c cable (Model: F2CU052BT1M-BLK) and it works with my Macbook Air 2018 and Samsung usb-c display.

Cable specs:

• usb-c 3.1 gen 2
• transfer data at 10 Gbps
• offer ultra HD 4K video resolution
• charge up to 100W (at 5A charging output)

Thanks for your help Luis!

I’m having the same problem. 2016 MacBook Pro w/ TouchBar and an external monitor (Samsung TV).

Up until yesterday I had zero issues connecting via the HDMI port of a UBC-C dongle (multi-function) on Sierra. Updated to Mojave last night and discovered the problem when i tried to connect to TV.

Similar to the original post, the TV recognizes that something is connected (it changes from no cable connected to no signal when plugged in) and my MBP shows me options for resolution of the external and what not, but the signal is not being sent.

Answers or solutions??

I've had this same problem. I'm on macOS Mojave (10.14.1), and here's what finally worked for me. I downloaded the DisplayLink driver v4.3 (beta 6) - restarted the computer, and voila. I'm on a 2017 iMac 5k, connected to a 4K UHD Samsung. Interesting note, according to their webpage, the permanent fix will be available in macOS 10.14.2. https://www.displaylink.com/downloads/macos

Interesting.

I would not have thought of that, because the OP mentioned a USB-C dock.

That I thought would support connecting an HDMI display without third party drivers.

I expect the OP to tell us if this fixed it; and I'd like to learn which exact dock you and the OP have.

That I thought would support connecting an HDMI display without third party drivers.

Right – would, should, and did support... In my case, it did with Sierra/High Sierra and no longer does with Mojave.

I expect the OP to tell us if this fixed it; and I'd like to learn which exact dock you and the OP have.

Not the OP, but apparently the same problem. It did NOT fix it in my case. I don't completely understand what DisplayLink is and what it has to do with (if anything?) HDMI. I've never had to download drivers before when connecting via HDMI on any of my previous MCB's that had HDMI ports. Doesn't make any sense to me for that to change now.

Apparently three people wrote in this thread about seemingly the same problem, and one of them mentioned displaylink as a solution.

It is unclear if this solution is at all relevant to the other two, because so far nobody has detailed what device is used to connect. For direct ubs-c to hdmi adapters, displaylink should be irrelevant, and there should be no need for installing any drivers. The displaylink thing has emerged in late versions of High Sierra because it was required for some people who were connecting displays via docks or adapters connected to USB-A ports on their macs. That feature was never supported in macOS without third party hacks.

The displaylink is irrelevant for the Apple adapter; I am not sure about the Satechi dock but I suspect it is not relevant either.

There is some mismatch between what the mac is outputting and what the display can accept, but it is not clear why (frame size, refresh rate?)

I have 3 external monitors all connected via HDMI. 1 x ASUS PB287Q 4K UHD (3840x2160) and 2 x ASUS PB278 (2560x1440). The 4K monitor works fine and one of the ASUS monitors work fine after upgrade to Mojave. The other one just refuses to come on. It's almost like the Mac has cached the EDID info and its corrupted or something and refuses to play nice. I've tried 4 different USB-C to HDMI dongles and 4 different cables. I've reset PRAM and SMC, still no luck. For the non-working monitor if I connect via DVI it works but then only at 1920x1080 and then intermittently blinks on and off every few minutes. I can connect another machine to the monitor via HDMI and it works just fine. It's something with this monitor and this Mac. It all worked fine prior to upgrading to Mojave. I may try downgrade to see if it fixes the issue.

I have a similar issue with a MBA 2018 (Mojave 10.14.1) not detecting a USB-C Samsung S27H850 monitor.

The monitor charges the MBA through usb-c to usb-c and I can even sync my iPhone through the monitor's usb hub feature with a usb-a to lightning cable.

Using HDMI (with mini-dp to hdmi dongle) on my old 2011 MBA also works - but the MBA 2018 with Mojave 10.14.1 doesn't detect the external display

What I think is happening is that the adapter you are using is one of those unsupported that used to work with the displaylink software.

Instead of using the approved method to convert the video signal to hdmi, these rely on video over usb, which does not work.

If you can try one of the Apple, Belkin or Macally adapters with an HDMI port I think that will work.

Just to add an extra data point, I've used the USB-C to HDMI converter from Apple, Anker, Sinstar, and StarTech, all will run other monitors fine. Just the combination of one specific monitor with one specific laptop does not work.