Kniel 120‑037‑01 CD 15.0,5 is a compact industrial AC‑DC switch‑mode power supply rated for 115/230 V input and dual output (±15 V). Common failure modes include degraded electrolytic capacitors on the secondary side, burnt or tripped overcurrent protection fuses, and failure of the internal switching regulator due to overheating. First‑check diagnostics: verify input voltage and polarity; measure output voltages with a multimeter while monitoring for ripple spikes; inspect all capacitors for bulging or leakage and test the overcurrent fuse/IC for continuity. If outputs are correct but load response is sluggish, check the main MOSFETs and gate driver circuitry for signs of thermal stress.[oss-gpt-20b]