Lost 5GHz

I have a AR750S firmware version 3.104. I never make any configuration changes, just check for updates. I plug the router in about once a month just for the weekend basically repeating a 2.4GHz WiFi signal.Today when I plugged in I do not see the availability of the AR750S 5GHz SSID. I do see the 2.4GHz SSID. In the settings it shows the 5GHz enabled. I even toggled the 5GHz off then back on, re-booted the router, but no success getting the 5GHz SSID to return. The 5GHz SSID has worked since updating to 3.104 and his not hidden. Are there any suggestions to troubleshoot this issue?

You’re sure it is not the device you’re trying to connect to the ar750 not seeing it? Many devices do not have 5GHz radios. However, I assume you’re using the same device you saw it available on before. Had to ask though.

I have tried from multiple devices. I have also used WiFi Analyzer, nothing there.

I would manually flash the 3.104 again, not saving the config settings. If using the browser UI method doesn’t fix it then I’d try the UBoot debrick method, but only if you’re familiar with it and comfortable doing it.

Not familiar with the debrick method. What I did try was deleting the radio thinking I could simply re-add it. But I do not see a way. Can that be accomplished somehow without a factory reset?

There is a way to add the interface back but takes some knowledge of openwrt and what it was before you deleted it. Again, best thing to do is reset/reflash to avoid further problems. All I got, maybe someone else will jump in. Good luck!

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I am having this same problem all of a sudden! My 5Ghz SSID is no longer broadcasting. I tried upgrading the firmware to a new version 3.201 but that did not solve the problem.

To be clear, it was working and randomly stopped. I hadn’t changed any settings or logged into the router in weeks. No matter what I try, I can’t get it to broadcast 5Ghz even though it says it is. Please help!

Can you check the log?

Seems that the 5G module is damaged.

That is exactly how it happened to me. I never did get it back. But I never tried a factory reset just an update like you.

Not exactly sure what I’m looking for in the log, but I am noticing that the 5G “signal bars” are blank for the 5Ghz SSID whereas they are 5/5 filled on the 2.4Ghz SSID (this is in the “Luci” status screen under Wireless, radio0.

I guess my next step is to factory reset, but I’d rather not have to start from scratch given that everything else is working (my devices are just using the 2.4Ghz signal even though it would be nice to have the 5Ghz option available)

I dont’k now if my case will help you.
I have an AR750S too.
Sometimes when rebooting, the 5GHz never starts.
I discovered it was the channel/frequency on 5Ghz. Some channels/frequencies make Wifi never starts.
In Luci>Wireless try Country at United States and try fixed channel like 36/40/149. Not Auto in Wifi channel.
In my AR750S I have 149 and on my 2 AR750 Creta I have 116 and 132 fixed channel.

Try it to see if it works.
Good luck!

If you used DFS channel, you will not see 5G starting immediately. But if you wait for like 1 minute, you may see the 5G. That is because DFS channels needs to detect radar signals and try to avoid that first.