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.
So I have an 820-3115 that has no image or chime. Iv'e checked all of the rails on the power aliases page in the schematic and found the only one that seems to be missing is PPVCORE_S0_AXG. it measures 0v. Shouldn't it be 1.05V?
Is this liquid spilled board?
Do you get now all voltages (apart of AXG)?
Do you note any level drop at VCORE aftter few seconds?
Did you try each RAM slot separately?
Known good working BIOS tested?