2018 Mac Mini - monitor problems

Tested on 10.14.1, 10.14.2, 10.14.3 and there is no difference, the problem persists. The Mac-mini starts normally with the monitor connected to the HDMI port, but when I connect the Cinema Display on the USB-C, it freezes and restarts. I found the crash logs and almost all the "previous shutdown cause" where with the code -20 and -63. I'm in contact with the Apple support and I'll post all the results here.

Confirmed. Cold boot does not work in 10.14.4 with usbc monitors ( two or one)

only workaround was a single monitor via hdmi

monitors that failed include hpz30, apple 30 inch cinema, acre, Brand new LG, etc.

clearly the monitor to bus communications is not properly working . It has nothing to do with the brand of monitor as I have tried four brands in different permutations, all with entirely unreliable cold boot, and random reliable wake from 22 hour sleep

I was on the phone with one of their senior support. I was able to get the crash logs using the log app with the command "log show --predicate 'eventMessage contains "Previous shutdown cause"' --last 24h" executed in the terminal app. In case any of you are having the mac mini restarting or freezing, this could help identify the code of the failure.

The support instructed me to collected a system diagnosys report via remote connection and send to a private link, so the engineers could analyse all the problems. So far it's not related to the USB-C ports, the thunderbolt 2 to thunderbolt 3 connector, the Cinema display, high temperatures, energy, damaged cable, apps and OS. 48 hours to get an answer (probably will arrive on monday (april fools day, for the record)

I am having a similar issue as all of you. In my particular case, I have two 27" Sceptre 4K displays, connected via USB-C to DisplayPort. I have this computer in my downstairs office and don't get to use it very often (unfortuantely), but I'll come back to it after a few days every so often and it'll be completely off.

Turning the machine back on usually doesn't work - no response from either monitor, with the exception of one of them briefly detects a signal and then goes back to sleep. I'll have to power cycle the machine several times, and only then will I'll be able to get a signal on one display and usually only after I connect an HDMI cable to it.

macOS indicates a kernel panic reboot, with BridgeOS being the underlying reason for the panic according to the console logs.

Yes

your symptoms match mine

the mini 2018 is not reliable - it does not reliably start up with multiple monitors after it has gone to sleep for more than a day or so. Or after a shutdown.

Maybe apple should put out a recall or otherwise refund the cost of the mini

or fix the problem

When is monitor issue going to be fixed? How much refund will buyers be getting for the poor excuse for they know about the problem! When did they know of problem and why is it not remedied asap! Apple needs new management that do not put crap out in the market and nonchalantly say they know they screwed up! The cost of apple products is very high for the degrading value since jobs died!!! So when will the no signal monitor be fixed I'm sure the problem was known before the first mini went off the shelf but the new management sold it any way!

For the record, I _thought_ mine was fixed, but it turned out that as soon as I shut it off a second time, the problem came back. Clearly some sort of issue with firmware/PRAM (because wiping PRAM on startup fixes it temporarily).

for a 1000 dollar piece of s..t it makes no sense that I should ever buy any more and I may well return this one since they know of problem with monitor no signal but seem to not give a ****! Very aggravating and sounds like some smollet tales! So when is fix if not yesterday gonna happen!!!

Last Saturday my Cinema display started working again. But as many others reported here, after it sleeps, the issue returned. Every time I connect the USB-C cable form the monitor, the Mac Mini free and restarts. No problems with the HDMI port.

I'm still waiting for the Apple engineers report (that would take only 48 hours accordingly to the Senior support that is handling my case).

this should be forced upon sellers of new mac mini to inform purchasers not to buy until problem is resolved!!! I can't believe they would sell this knowing the mini does not always recognize the monitor and what other little smallest are they hiding???

After sending some system dialogs, the Apple engineers find an issue with Duet App , that makes iPad/iPhone an extra display. After uninstalling the app, made test on the 4 USB-C ports. Each one gives the same error, Kernel Panic error with the codes -20 and -63. I didn't find anything besides that.

After sending them 2 system diagnoses and nothing on why this is happening, they verified that there is an issue with the USB-C ports and external monitors. I have external hard drives using the USB-C ports with no problem and another display connected on the HDMI port working normally.

they advised to go to an Apple authorized repair center. Let's see what they will find something.

I received an unsolicited phone call from an Apple engineer on my way home from the office on Friday regarding my post here. I couldn't talk to him about my issue because I was driving and away from my computer, but we've made arrangements to speak about this issue tomorrow.

I'll let everybody know how it works out.

Not fake. Literally the only people that would be able to contact me on the phone through this website are people with access to my Apple ID information (which, would be Apple, unless they’ve been compromised). I’ve also received correspondence from them and have previously corresponded with engineers watching this forum on other issues I’ve experienced over the years.

Thank you for your concern.

I just got mine working with usb to hdmi male cable and an adapter DVI on monitor to hdmi female! (2) bi-directional Adapter 6.99 on amazon and cord 12.99

taking back 2 35.00 cords to store for refund that did not work!!! The cords and or adapter should be sold as part of the **** computer it will not work without proper power supply! Now monitor comes on when computer comes on!!

I just got mine working with usb to hdmi male cable and an adapter DVI on monitor to hdmi female! (2) bi-directional Adapter 6.99 on amazon and cord 12.99

taking back 2 35.00 cords to store for refund that did not work!!! The cords and or adapter should be sold as part of the **** computer it will not work without proper power supply! Now monitor comes on when computer comes on!!