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.
Liquid damage on this board.. more specifically in u5400.. Already cleaned and component replaced.. But fans still in high speed after ~30 sec.. ant help»?
What does Apple Diagnostics give you for error codes?
Do you have completely assembled the board into its casing? Otherwise it will indeed run at full speed because various sensors (like in the trackpad) won't be connected.