MTS 463989‑01G is a high‑current industrial AC‑DC power supply (switchmode) used to feed servo drives and control electronics. Common failure modes for this class include blown or leaky electrolytic capacitors on the input filter, degraded output voltage regulation due to failed MOSFETs or rectifier diodes, and overheating of the heat sink causing thermal shutdown. First‑check steps: verify mains input voltage and polarity, measure output rails against spec while monitoring temperature; inspect for bulging or leaking capacitors, and check for any visible arcing or burnt components on the PCB. If the supply fails to start, review any error codes from the host controller and confirm that all I/O connectors are secure.[oss-gpt-20b]