Why this symptom gets misread
When WiFi disappears on an iPhone, people understandably think about settings, a software update, antenna issues or a bad WiFi chip. Sometimes that is not where the problem lives. The iPhone 12-series sandwich board design introduces another layer of failure mode: the fault can be caused by board-layer relationship problems rather than a straightforward top-level part failure.
What the case showed
This confirmed Fixaviour case was logged as iPhone 12 Pro — No WiFi — Sandwich layering fault. The root cause note was direct: sandwich layer misalignment causing WiFi IC fault. That makes it a good reminder that board-level diagnosis is not just about changing one obvious chip. It is also about understanding how the board is built and where the failure path really sits.
What fixed it
The repair entry recorded the fix as re-layered sandwich correctly. The outcome was marked Fully Fixed. In practical terms, that means the bench process corrected the board relationship itself rather than treating the device like a normal parts-swap repair.