ASUS RT-AC88U hardware/software defect identification

Hello everyone,

first of all incredible forum! Was reading through it half a day finding a lot of relevant information.

I'm a repair enthusiast, wanted to upgrade my home network so decided to play around with router repairs.. got myself a defective RT-AC88U - really nice build quality. Was hoping for a firmware problem but it seams I got myself a hardware problem (not a problem though, as I like to fix these too)..

When I power it up, it responds quite interestingly haven't found it...

ASUS RT-AC88U hardware/software defect identification