Didde MaP40‑3000 is a 40 W chassis‑mount AC‑DC power supply delivering +5 V/3 A, +12 V/2 A and –12 V/0.3 A outputs with an 85–264 VAC input range. Common failure points for this model include degraded electrolytic capacitors on the output rails, fan or heat‑sink overheating leading to thermal shutdown, and shorted or open rectifier diodes that cause voltage sag or over‑voltage protection trips. First‑check diagnostics: verify input voltage and polarity with a multimeter; measure each output rail under no load and then at full load to confirm correct voltages and current limits; inspect the board for bulging or leaking capacitors, burnt components, and ensure the cooling fan is operating and unobstructed.[oss-gpt-20b]