The Omnivision E14DC‑ZL is a 14″ color CRT operator interface used on Mazak/Mazatrol and Mitsubishi CNC systems, powered from 100–240 VAC. Common failure modes include tube burnout or phosphor degradation causing flicker or no image, power supply board faults (transformers, rectifiers), and capacitor leakage in the high‑voltage section. First‑check diagnostics: verify mains voltage and monitor input with a multimeter; inspect the CRT for visible cracks or burn marks; test the power supply output rails against spec values and check for blown capacitors or overheating components. If those checks are normal, review any error codes displayed on the host controller and perform a visual inspection of the back‑panel connector pins for corrosion or loose contacts.[oss-gpt-20b]