WRT3200ACM - 5GHz radio not up (on wireless list) on openwrt 19.07.3 and on original FW


my parents have 2 WRT3200ACM routers i gave them, both with latest build of openwrt (19.07.3). The first one connects to the internet upstairs and distributes Wifi to the 2nd floor. The second one is connected downstairs, using LAN cable from the 2nd floor, and with DHCP disabled (It has its own IP address).

The Wifi network structure is the same one both-Same SSID for both 2.4 and 5 bands, but the channels are (obviously) different in both floors. 2.4 works on 40MHZ width and the 5GHz works on 80MHZ.

The router upstairs is working fine-you can see 3 radios, with 1 disabled (the one used for radar probing with low BW).

The router downstairs has a problem-the 2.4 wifi band is up and running. The 5 band is not working (and not up). the 3rd radio (which is disabled by default) is seen.

I've made the following steps to solve the issue but the problem persists:

  1. Since the routers are the same in configuration (except channel) I've copy-pasted the contents of the /etc/config/wireless file from the 1st router to the 2nd using winscp with its file editor. however, when the 2nd router rebooted after the file copy, the contents has changed and reverted back to what it was prior to change.
  2. I flashed a brand new factory image of openwrt upgrade version to the 2nd router. after reboot-the same.
  3. I flashed a new factory image of openwrt squashfs new build to the 2nd router. still not working.
  4. i did a factory reset using the command firstboot && reboot now . no luck.
  5. I flashed the latest original linksys fw build (Ver. There, you can see the 5ghz radio as gnac (i think it's the 3rd disabled radio that is used for radar).
  6. I flashed david502 openwrt build.

How can i solve the issue of the 5ghz band not working at all? Also, the 160MHZ BW is not available on both routers (greyed out).

By the looks of it from your screenshot, there is a mixup with th radios. Marvell 88W8964 802.11bgn should be radio 1 and Marvell 88W8964 802.11nac should be radio 0. If it helps at all I can share my wireless config?

sure,why not?
the funny thing is that i copied the configuration from the first router which is working ok and has 5ghz working as usual. after i copy the configuration i see a bgn radio designated as "generic" in the "wireless" section.

Something else came to my mind, I found the below comands to regenerate the config from the actual router itself, of course this fill remains untouched on alot of occasions, like the ones you mentioned. But this should regenerate the config for that specific router, I know you mentioned that they are both exactly the same, but it is just a longshot.

rm -f /etc/config/wireless
wifi config

this was found on https://openwrt.org/docs/guide-user/network/wifi/basic

Let's start with the basics.
Does the 5 GHz radio work ok with the Linksys OEM firmware?
(Your earlier message was a bit vague on that. Possibly only the unused third radio was usable?)

If OEM firmware does not work, then there is probably a hardware failure. You might look closer at the logs visible in OEM.

The 3rd radio was working with the 2.4g radio in the linksys fw.
I'm attaching openwrt david's build log on the faulty router.

Something about 5G radio not enabled but 2.4g is working:

That message is normal from the firmware. It just indicates phy0 is capable of 2.4GHz and not 5GHz.
You should see another message later about phy1 indicating the opposite.

I agree that it is strange that phy0 is the 2.4 wifi, it is normally the opposite which may indicate something wrong with your config. Definitely share it here.

After I flashed again the original linksys FW (latest), the 5GHz band began to work again.
Looks like i'll leave it that way, so one router will be with openwrt and the other with Linksys FW. Perhaps the driver of openwrt is faulty.

OpenWrt works ok with wrt3200acm.

As the OEM firmware works, your hardware should be ok.
Then it is about your config (or the specific openwrt build).

You might try the official OpenWrt image, and after flashing clear the settings once more via reset.
( Or if you want, you could try my CPU frequency scaling test build for wrt3200acm. My radios work normally with it. Download is available from the forum thread about CPU frequency)

But in any case, please do not restore any config settings from backup, but just reconfigure from scratch.

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I have the same problem. I am pretty sure that this is not a configuration error. After flashing two WRT3200ACM's with exactly the same settings and OpenWRT version one had problems with the 5GHz Wifi. It fails to start at router start up.
I suspect the power. Maybe my power supply is too weak to initialize the radio at the demanded strength. I returned the second one to my friend so I cannot check this. After reducing transmitting power (because I added an extra accesspoint in my home) the problem dit not occur again.