Fixing My ASUS RT-AC86U - Blown MT3125 IC

Symptom:

When I plugged it in, only the Eth4 LED lit up. Nothing else. No power light, no signs of booting. 

Research:

I found numerous posts indicating a common fault for this router: the MT3125 voltage regulator IC. So I proceeded to order the IC to attempt replacement. 

Repair:

I searched YouTube for videos on how to disassemble the router. I found this video helpful.
As expected, when I opened it up, there is a mini crater on the MT3125 IC:



When I pulled the faulty IC off, a few pads got ripped, but they seem to be NC(not connected) pads. I think 1 was ground as well, but there's a huge center ground plane so it doesn't really matter. The router was revived after replacing the IC. 

ASUS RT-AC86U circuit board with damaged pads after removing the MT3125 IC
Ripped a few NC pads


I read on forums that the chip gets hot, and sure enough, when I use my thermal camera on it, it shows around 60-70 Celsius on boot. I stacked up a few pieces of my thermal pads so hopefully the heat can escape to the metal piece and not blow up so soon. 

Thermal image showing the router IC at 63 degrees Celsius after power-on
Reaches 63 Celsius seconds after powering on

Thermal image of the router after adding a thermal pad
After adding thermal pad - hopefully it helps



Other useful links: 


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