The Fanuc A16B‑2203‑0080/02B is a Loader Control Circuit Board used in FANUC CNC loader machines, integrating power regulation, signal conditioning and control logic for the machine’s spindle and servo drives. Common failure modes reported include overheating of the main voltage regulator IC, burnt or cracked trace on the high‑current input pads, and degradation of surface‑mount MOSFETs that supply the motor driver circuits; these often manifest as intermittent loss of spindle motion or “control board reset” error codes. For initial diagnostics, verify that the 24 V DC power rail is within spec, inspect the board for visible burn marks or cracked traces around the regulator and MOSFET packages, and check all I/O signals (e.g., spindle speed, torque limit) against the machine’s diagnostic display to isolate a faulty driver module.[oss-gpt-20b]