OKI Telecom MM8 is a compact AC‑to‑DC power supply module used in industrial control panels and telecom equipment, typically rated around 80–120 W with a 12 V or 24 V output. Common failure modes include degraded capacitors (especially electrolytic), burnt-out rectifier diodes, or overheating of the internal switching regulator due to dust accumulation or poor ventilation. First‑check diagnostics: verify input voltage and polarity on the AC terminals; measure output voltage with a multimeter while the unit is powered; inspect for visible signs of component failure such as bulging caps, scorch marks, or loose solder joints; and review any error codes or indicator LEDs that may point to over‑current or short‑circuit protection activation.[oss-gpt-20b]