For $29/mo, we provide access to advanced level technicians who will answer your questions on any Macbook board related matter to the best of their knowledge promptly & walk you through how to solve your problem so you can deliver a working board to your customer.
This one had liquid but board looks clean no corrosion. There is PP3v42 and KBD_ONOFF_L goes low with power button. This is a 2015 so no ASD. Is there measurements or test you would like me to run/take that would help you understand what could be the problem. The machine seems to function fine other than the power button issue.
the basics, PPBUS_G3H, green/orange light, this board should turn on just by pluging in charger, so forget about power button for now, the fan will not spin untill the processor gets really hot, so forget about fan spin.. CPU Vcore present??