Any issue connecting M5 MacBook Pro 14" to an external portable monitor?

[hajime]

Hello, I had a monitor connected to a PC via HDMI and powered by USB-C adaptor. It was working fine. However, when I disconnected the HDMI cable and connected a Thunderbolt 4 cable between the M5 MacBook Pro and the monitor, no signal and the monitor got shut down for power saving. MacBook Air M4 15" and MacBook Pro M4 Pro 16" had no such issue. Is there something wrong with the M5 MacBook Pro 14"? Anybody else has similar problem?

 

[hajime]

Anybody else has issues connecting with an external monitor? I went to an Apple store and showed a guy the problem. He had no idea what is wrong but told me to report to Apple so they would get it fixed!

 

[raythompsontn]

May be an issue of not enough power to the monitor from the MacBook. As to why only one machine is having issues, I would suggest contacting Apple support rather than one of the clowns at the Apple Store.

 

[hajime]

May be an issue of not enough power to the monitor from the MacBook. As to why only one machine is having issues, I would suggest contacting Apple support rather than one of the clowns at the Apple Store.

Apple support also have clowns working there too.

I have two cables to the monitor. One from a power source and the other from the Mac. No problem doing this with M4 MacBook Air 15" and M4 Pro MacBook Pro 16".

Do you mean other M5 MacBook Pro 14" 2025 users can connect to external monitor without issue?

Some M4 series MacBook Pro users seem to have issues after upgrading to macOS26. Mine came with it out of the box so I don't know if it is problem with the machine or the OS.

External Monitor Not Detected After macOS… - Apple Community

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