need help AX-82U 5GHZ not working

[mengroup]

Short Story: I have 2 AX-82U, and they both have the same issue where 5ghz stopped working completely

Long Story: 2 router meshed together to cover my whole house. The 5ghz failed back to back. Very frustrated! Everything else work, except the 5ghz.
I am tried to figured out what is going on with the router. so restart, reset, and update the FW, enable/disable 5ghz or 2ghz. Nothing changes. But i noticed something, the led light for both 2ghz and 5ghz lit, only the 5ghz not showing on the wifi list. when i use the wan port the 5ghz led off but fine if you use any Ethernet ports, regardless still pick up no 5ghz signal.

when I change 5ghz setting like channels, my laptop can pick up weak 5ghz signal, but not my phone even the router is just right next.

I also opened up to see any antenna broken, but they all in good shape and firmly connected to the board.

I went out of options. Any advises. Is this a common problem for Asus routers, or common on the AX series, because my AC1900 are working fine without any issues all those years.

 

[bennor]

It may help if you include the firmware version running on both routers.
How are the two units connected? Via WiFi backhaul or by ethernet backhaul?

 

[OzarkEdge]

Short Story: I have 2 AX-82U, and they both have the same issue where 5ghz stopped working completely

Long Story: 2 router meshed together to cover my whole house. The 5ghz failed back to back. Very frustrated! Everything else work, except the 5ghz.
I am tried to figured out what is going on with the router. so restart, reset, and update the FW, enable/disable 5ghz or 2ghz. Nothing changes. But i noticed something, the led light for both 2ghz and 5ghz lit, only the 5ghz not showing on the wifi list. when i use the wan port the 5ghz led off but fine if you use any Ethernet ports, regardless still pick up no 5ghz signal.

when I change 5ghz setting like channels, my laptop can pick up weak 5ghz signal, but not my phone even the router is just right next.

I also opened up to see any antenna broken, but they all in good shape and firmly connected to the board.

I went out of options. Any advises. Is this a common problem for Asus routers, or common on the AX series, because my AC1900 are working fine without any issues all those years.

Sounds power related. Test a router with nothing or near nothing connected to it in case some connected cabling or device is messing with its circuits.

Check your wall outlet for loose neutral and ground connections. Try a different wall outlet. Check your building Earth Ground to be sure it is made and solid.

Same for the ISP cable... if cable Internet, make sure the coax shield is grounded at the demarc using a grounding block coupler bonded to the building Earth Ground.

Use both power adapters to test the same one router in case a power adapter is not working well.

Something may have already damaged the 5.0 radios.

OE

 

[Tech9]

I went out of options. Any advises.

There was a repost of 2x RT-AX82U in AiMesh (exactly your situation) both damaged in recent malware attack. If you had AiCloud enabled and your routers ask for country code after reset - read the thread below. Both routers showing the same symptoms at the same time is unlikely individual device issue (like power supply).

Malware damaging ASUS routers?

This malware damaging Asus routers has to be described in a sticky thread with a warning sign! Update: Asus is releasing patched firmware for multiple models. Check for firmware updates! The changelog for most firmware releases contains the following: 1. Strengthened input validation and data...

www.snbforums.com

 

[mengroup]

It may help if you include the firmware version running on both routers.
How are the two units connected? Via WiFi backhaul or by ethernet backhaul?

The current FW is 3.0.0.4.388_25024.

The 2 units are connected through back-haul

Two three months ago, the one that setup as main failed (no 5ghz) right before it fail it was using asus merlin (can't record the FW number). Then I use the node (another AX82U) as main and AC1900 as node. After about a month, it failed too, also the 5ghz problem

 

[mengroup]

There was a repost of 2x RT-AX82U in AiMesh (exactly your situation) both damaged in recent malware attack. If you had AiCloud enabled and your routers ask for country code after reset - read the thread below. Both routers showing the same symptoms at the same time is unlikely individual device issue (like power supply).

Malware damaging ASUS routers?

This malware damaging Asus routers has to be described in a sticky thread with a warning sign! Update: Asus is releasing patched firmware for multiple models. Check for firmware updates! The changelog for most firmware releases contains the following: 1. Strengthened input validation and data...

www.snbforums.com

I don't think I touch the AIcloud setting, is it enabled by default. But ill look into the thread you given

How can i tell my units are attacked? and Any remedy to it?

 

[Tech9]

What channels are you using on 5GHz band?

 

[mengroup]

What channels are you using on 5GHz band?

I tried different channels to test it out. Around 100 to 160 (can't remember the specific channel number), my laptop seem to pick up tiny 5ghz signals but not my phone, Even they are right next to each others.

 

[Tech9]

can't remember the specific channel number

This is quite important because the DFS range may not be available or stable in your area and this will trip 5GHz radios with wait time between 1-10 minutes depending on your region. Non-DFS channels with 80MHz bandwidth are 36-48 and 149-161 (if available).