Tutorial How to fix a dead RT-AC86U, only LAN 4 light on

[thelonelycoder]

Mick over from the YouTube channel Buy it Fix it has a new video out fixing a dead RT-AC86U.
Many of us have seen the exact same problem with that model, including me. Mine has long since been recycled but if you're really good at soldering, give it a go.
And have a guess what firmware this router runs on

Any of the users here recognize the initial Dzelsky SSID?

 

[Tech9]

I brought home 10 dead AC86Us some years back, used 4 for parts donors and restored 5. This very same MT3125 issue was present in 4, the other 2 had burned WAN port, one was the coils (fixed) the other was the SoC (non fixable). Kept 4 for experiments, 1 failed some time after again. One was heavily modified with copper shims, Arctic Silver, dual 5V fans with case cutouts, blue LEDs, etc. One was converted to GT-AC2900 and was running stock GT firmware with unlocked 160MHz channels (no AC 160MHz capable client was available to test though). I had some fun with this model.

 

[Viktor Jaep]

I brought home 10 dead AC86Us some years back, used 4 for parts donors and restored 5. This very same MT3125 issue was present in 4, the other 2 had burned WAN port, one was the coils (fixed) the other was the SoC (non fixable). Kept 4 for experiments, 1 failed some time after again. One was heavily modified with copper shims, Arctic Silver, dual 5V fans with case cutouts, blue LEDs, etc. One was converted to GT-AC2900 and was running stock GT firmware with unlocked 160MHz channels (no AC 160MHz capable client was available to test though). I had some fun with this model.

Don't forget that one that you used for RTRHTR testing!

 

[Tech9]

This one was a different model, more reliable aviation approved RT-AC66U B1. And I'm not forgetting anything around RTRHTR testing.

 

[Tech9]

I actually remember removing and reballing radio ICs for intermittent 2.4GHz issue, but this was valid for other models like RT-AX88U and not isolated to RT-AC86U only. Perhaps RoHS thermal stress issue. Other routers and consumer electronics suffer from it as well. Passive cooling - more often.