Linksys EA4500v1 5GHz WiFi not visible


Today i upgraded my Linksys EA4500 V1 with openwrt ( openwrt-18.06.4-kirkwood-linksys_viper-squashfs-factory.bin).

After install everything works fine except that 5ghz is not available. The 5GHz Wifi works correctly on stock firmware.
Do you have any idea how can I correct this error?
Thanks in advance.

Sometimes OpenWrt gets a bit freaky with the WiFi. Just go in make a change to the channel, set it to something available, save it and then reboot it and wait. It should eventually come up. It's happened to me a few times on various routers.

Unless it's something more obvious like your SSID is not broadcasting in the settings, so check that first.