Wierd problem on an AC86U

[charlesbuzz]

Hello

Since friday, I have this wierd issue where all my devices, even if they are connected to my AC86U (wireless log and DHCP leases prove it) act very slow or drop and reconnect and the signal range drop a lot.
Connected devices work correctly

This is not a new installation, I have this setup working correctly since more than 6 mounth

Speedtest not working even if I have 2 bars signal on my iPhone

The problem happend on 2 differents router , both RT-AC86U (no Aimesh, not connected at the same time, I bouth the second one to diagnose) both have the same problem

The configuration look like this

Router: RT-AC86U
Firware: 3.0.0.4.386.42643 and now 3.0.0.4.386_44470
Smartconnect
2.4ghz channel 6 (20/40 mhz)
5 ghz channel 149 (20/40/80 mhz)
Multi-User MIMO only on 5ghz band
no Airtime Fairness for both bands
no Aimesh node

type of devices: iPhone/iPad/PC/Wemo/Mysa/RainMachine/google home/Chrome cast etc...

where do I start to find this problem ?

thanks for your help

 

[bbunge]

Use 20 MHz for 2.4 GHz and 80 MHz for 5 GHz (no DFS channels).

 

[Tech9]

where do I start to find this problem ?

RT-AC86U routers are sensitive to high ambient temperature. When the CPU reaches 100C the thermal protection shuts down cores. You can check the CPU temperature in stock Asuswrt by logging in GUI and clicking on the link below:

router.asus.com/ajax_coretmp.asp

What else is running on the router? Do you have external USB storage attached, what type and what it is used for?

 

[charlesbuzz]

RT-AC86U routers are sensitive to high ambient temperature. When the CPU reaches 100C the thermal protection shuts down cores. You can check the CPU temperature in stock Asuswrt by logging in GUI and clicking on the link below:

router.asus.com/ajax_coretmp.asp

What else is running on the router? Do you have external USB storage attached?

this is what I get
fanctrl_info = ; curr_cpuTemp = "84.648"; curr_rxData = fanctrl_info[3]; curr_coreTmp_2 = fanctrl_info[1]; curr_coreTmp_5 = fanctrl_info[2];

what is the normal temperature of operation for tis cpu?

nothing else is running

 

[Tech9]

what is the normal temperature of operation for tis cpu?

There is no normal. It varies with ambient temperature. Yours is fine, above 90-95C is a concern.

 

[Tech9]

nothing else is running

Did you check what's going on with Wi-Fi channels around? Use your preferred Wi-Fi Analyzer app. Is the issue present on both 2.4GHz and 5GHz bands?

 

[Tech9]

both have the same problem

Did you save and restore the settings from Router 1 to Router 2?

 

[charlesbuzz]

Did you save and restore the settings from Router 1 to Router 2?

no, I configured from scratch on both

 

[charlesbuzz]

Did you check what's going on with Wi-Fi channels around? Use your preferred Wi-Fi Analyzer app. Is the issue present on both 2.4GHz and 5GHz bands?

seems to be on the 2.4 only, but I will check wich channel is less crouded

 

[charlesbuzz]

is it possible that I have a Wifi device that is causing this problem ?

 

[charlesbuzz]

it is defenetly a 2.4 ghz problem if I refer to the ping test
5ghz to lan around 10-20 ms
5ghz to 5ghz around 20-50 ms
5ghz to 2.4ghz around 500-1000 ms with drop packets
lan to 2.4ghz around 500-1000 ms with drop packets

 

[Tech9]

This router has bad reliability history. One of the many common complaints is 2.4GHz radio failure. Many folks on this forum lost one or more AC86Us. What I found inside and possible failure causes is here. Where did you get the second unit from? Is it a new router or used?

 

[Tech9]

is it possible that I have a Wifi device that is causing this problem ?

Yes. Start disconnecting devices on 2.4GHz band one by one and test again. Hopefully you find a bad client, not a bad router.

 

[MeshHead]

RT-AC86U routers are sensitive to high ambient temperature. When the CPU reaches 100C the thermal protection shuts down cores. You can check the CPU temperature in stock Asuswrt by logging in GUI and clicking on the link below:

router.asus.com/ajax_coretmp.asp

What else is running on the router? Do you have external USB storage attached, what type and what it is used for?

My solution as a precautionary.