amcc — Processor / logic board
On an iPhone 15 Pro Max, the error “AMCC … Cache Data Ram One-Bit error” (ECC) is interpreted by iFixit as an error in the processor's internal cache memory.
iPhone
SoC (memory / cache controller) — not repairable short of a board replacement
Low confidenceVerified sourceProcessor / logic board
First check
DFU restore to rule out firmware; if recurring, logic board / warranty.