Asus-N66U 2.4 GZ seems to be dead

[SMW]

I have an Asus RT-N66U router setup to use broadcast both 2.4GZ and 5GZ signals.
I also have an Asus RT-N56U setup as an wireless repeater which connects to the N66U via 5GZ and allows devices to connect via 2.4GZ.

Today the 2.4 Gz on the N66U router won't allow devices to connect. Devices can see it however one of a few things will happen.

1. PC will showed to be connected but will have the yellow "!" and won't connect to the internet or the router admin screen
2. Won't connect to the router at all.

This happens with iphones, ipads, multiple laptops, and anything else connected to the 2.4 GHz

The LAN and 5Ghz works great along with the 2.4gz connection of the RT-N56U.

I updated to the latest stock firmware about a week ago with no issues 3.0.0.4.380.3264. (I now know that might have been a mistake).


I've restored the RT-N66U to its factory defaults and set it up again from scratch. Same issues. It will connect to the 2.4 Gz for around 30 seconds then bam no internet connection and unable to log into router.


TLDR; RT-N66U's 2.4gz channel is visible but nothing can connect to it (or works for 30 secs then stops). 5Ghz and Lan works fine.


Any ideas? What info do you need to troubleshoot.

 

[SMW]

Did another factory reset and if I don't change any settings the 2.4 GZ works fine. Leaving the SSID as ASUS and adding a WPA passcode it seems to be working fine.

I change the SSID back to the old SSID (2.4GHz channel) and connection go to crap. Can't load webpages and the admin page loads very slow if at all. If I log in via a 5Ghz device and change the SSID back to "ASUS" everything seems to be fine.

If I change the name to "Test" it works fine. If I change it to 10 letters ("testtestte") like the old SSID it works fine.

Go back to the original SSID and it all goes to crap. Speeds are 2mb if it connects (LAN is 120MB)

the old SSID was "usquebaugh"


I'm at a loss

 

[mstombs]

Use a PC/mobile app to choose the best free channel number - auto may not work. Delete the connection profile on your client machines and reconnect. There are reports you can go back to earlier firmwares using the router repair tool or CFE web console - it is just web gui downgrades currently blocked.

 

[SMW]

Use a PC/mobile app to choose the best free channel number - auto may not work. Delete the connection profile on your client machines and reconnect. There are reports you can go back to earlier firmwares using the router repair tool or CFE web console - it is just web gui downgrades currently blocked.

I edited my last post.... very strange patterns.

The issue happens even on a device that never been connect to my network.

 

[mstombs]

Very strange, do check with a 'wifi analyzer' type of app. I have had a problem where a neighbours router, presumably on auto kept moving to an adjacent channel whenever I moved mine. On 2.4 GHz you really need to have 3 clear channels between you and your neighbour. Also do set it to 20MHz width, due to 2.4 congestion I have found 40Hz often poor.

 

[SMW]

Very strange, do check with a 'wifi analyzer' type of app. I have had a problem where a neighbours router, presumably on auto kept moving to an adjacent channel whenever I moved mine. On 2.4 GHz you really need to have 3 clear channels between you and your neighbour. Also do set it to 20MHz width, due to 2.4 congestion I have found 40Hz often poor.

Doesn't matter what channel I select or the 20mhz/40mhz. ran wifi analyzers and picked various channels to test still have the same issue. If I use my old SSID the connection stops working.

 

[Rossboo]

I updated last night and I am having the exact same issues. The firmware must be broken. Did you manage to find an answer to the problem?

 

[SMW]

I updated last night and I am having the exact same issues. The firmware must be broken. Did you manage to find an answer to the problem?

I ended up placing the router in "recovery mode" and used the Asus Firmware Restoration software to upload a different firmware. You can uses an older Asus firmware however I ended up putting Merlin's firmware on it.

All seems to be working now.


Select the "OS" to "Others" and all the old firmwares will show up.
https://www.asus.com/us/Networking/RTN66U/HelpDesk_Download/

 

[Rick Smith]

Wow this is a maddening issue that I too experienced before and again with my RT-N66u. My RT-N66U has this issue around the same time as you. How strange.

I don't understand why we have this issue. I also used Merlin's firmware and it didn't resolve it.

I switched to Netgear and all is well (after figuring out an issue)... I just don't understand why it's so frustrating!