Help needed: After 1 year, 2.4G stop working, 5G works fine (Asus RT-AC68U, TM-1900, Firmware Merlin

[Volfi]

Hm, my AC88U started acting strangely lately, devices not being able to connect reliaby to 2.4GHz.
AC86U works fine.
Nothing helps, complete wipe, stock firmware...
Seems to me multiple Asus routers develop (hardware?) problems over time on 2.4GHz.

 

[First Last]

So I was able to fix this problem and included a long post how to and it's been removed so, FYI, those having 2.4ghz problems. It's not a bad chip. It's the firmware. Sorry I'm not allowed to give more info.

 

[TLight]

So I was able to fix this problem and included a long post how to and it's been removed so, FYI, those having 2.4ghz problems. It's not a bad chip. It's the firmware. Sorry I'm not allowed to give more info.

Well this is frustrating. What type of solution would they not allow you to post? I am having a similar problem (see: https://www.snbforums.com/threads/rt-ac87u-2-4ghz-problem.64153/) and would love to see your solution, even if it turns out not to apply to me.

 

[First Last]

Basically, I just installed the ac68u firmware and then reset nvram (hold wps button and turn on, hold until power light flashes). You lose all your settings but you get back your 2.4ghz so worth it. I really thought my chip was bad but it's working great now.

 

[First Last]

I think there are driver issues with the mer firmware.

 

[TLight]

I think there are driver issues with the mer firmware.

So you went back to stock ASUS firmware?

 

[First Last]

yes

 

[TLight]

yes

OK I will look into that. Download from ASUS website? I actually have RT-AC87U. One is my router and both 5 and 2.4 Ghz works well and reliably. I have a 2nd RT-AC87U, configured as an Access Point, that the 5 Mhz works perfectly, but the 2.4 will not. I could try flashing just the AP box back to stock and see if that works. Strange that one works but not the other.

 

[First Last]

Maybe try WPS reset first just to make sure (I explained before). I recommended putting your settings back manually and not using the CFG file if it's working ok.

 

[TLight]

Maybe try WPS reset first just to make sure (I explained before). I recommended putting your settings back manually and not using the CFG file if it's working ok.

Sorry, not sure I'm clear. (Still a bit of a neophyte.). By WPS reset you're referring to the nvram clear process you described? BTW, I am not using WPS (WiFi Protected Setup) if that is what you're referring to. It is disabled.

 

[First Last]

Yes, nvram clear process.

 

[mobileineurope]

When 2.4 GHz is not working while 5 GHz is working ok - it can be caused by using the USB 3.0 ports. Several people including me have seen this happen especially when using unshielded cables. USB 3.0 runs on the same frequencies as 2.4GHz WiFi. Try to dismount any USB 3.0 devices - or change the ports to operate as 2.0 ports.

 

[TLight]

When 2.4 GHz is not working while 5 GHz is working ok - it can be caused by using the USB 3.0 ports. Several people including me have seen this happen especially when using unshielded cables. USB 3.0 runs on the same frequencies as 2.4GHz WiFi. Try to dismount any USB 3.0 devices - or change the ports to operate as 2.0 ports.

In my case, I am not or have I ever used the USB ports on the router. Thanks for the info however.

 

[TLight]

Yes, nvram clear process.

Dumb question: Is this clear process the same as pressing the "factory reset" button on the back of the router, and/or doing a factory reset from the firmware? My model is different from yours (RT-AC87U).

 

[ColinTaylor]

Dumb question: Is this clear process the same as pressing the "factory reset" button on the back of the router, and/or doing a factory reset from the firmware? My model is different from yours (RT-AC87U).

https://www.snbforums.com/threads/faq-nvram-and-factory-default-reset.22822/

How do I do a factory default reset?
Multiple ways to do so, which will depend on your particular situation.

If your router fails to boot due to corrupted/invalid nvram settings, then you will have to turn off the router, press the WPS button (on Asus routers), then turn on the router. Wait about 10 seconds, then release the WPS button.

If the router is booting correctly, then you can use any of the following:

• While router is running, press the reset button for about 5 secs, then release it. Router will then reboot.
• From the webui, on the same page where you can save/restore saved settings, there is a button to restore factory default values

 

[TLight]

https://www.snbforums.com/threads/faq-nvram-and-factory-default-reset.22822/

Boy oh boy this is a tough one. More and more looking like this is not a hardware or firmware (driver) problem. I'd be interested in your opinion to this point: https://www.snbforums.com/threads/rt-ac87u-2-4ghz-problem.64153/#post-584955

 

[seth_space]

Just something to try. Disable roaming assistant on all channels.
It solved a lot of strange 2,4 problems at my house.
(found at: wireless, Professional)

 

[TLight]

Just something to try. Disable roaming assistant on all channels.
It solved a lot of strange 2,4 problems at my house.
(found at: wireless, Professional)

Thanks, but this was already disabled on all frequencies on both router/AP in my installation.

 

[TLight]

I think I figured out a solution to my problem with 2.4GHz on my AP router. Not sure how much it applies to other 2.4GHz issues here, but here it is: https://www.snbforums.com/threads/rt-ac87u-2-4ghz-problem.64153/#post-585064

 

[Dragoner]

When 2.4 GHz is not working while 5 GHz is working ok - it can be caused by using the USB 3.0 ports. Several people including me have seen this happen especially when using unshielded cables. USB 3.0 runs on the same frequencies as 2.4GHz WiFi. Try to dismount any USB 3.0 devices - or change the ports to operate as 2.0 ports.

I used a short 12-inch USB extension cable to plug in a USB disk to the USB port on my RT-AX86U to make accessing the port easier.
That's when my 2.4GHz network started having problems. The network just wouldn't show up at all.

Your solution helped me. After unplugging the USB extension cable, my problem was solved.