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.
Inspect LIO connector.
Try known good LIO board/connector.
Check for short or low resistance on all power rails which go to J9500; when it is connected.
Yes using the adapter OR using an NON OEM charger causes lots of issues with 2015 machines for some reason. Always need OEM chargers for these no matter what