The Markem‑Imaje UI 100 is a discontinued operator interface console used with SmartLase label printers and laser coders, featuring a 9‑pin connector and soft‑touch pushbuttons. Common failure points for this class of industrial HMI panels include burnt or fried input/output circuitry, degraded button contacts, and power supply board faults such as blown capacitors or damaged voltage regulators. Initial checks should verify that the unit receives proper 24 V DC (or specified) input, inspect the front panel buttons for continuity and physical wear, and review any diagnostic LEDs or error codes displayed on the LCD. If power is present but no display appears, test the main board’s power rails and look for obvious component damage before proceeding to deeper diagnostics.[oss-gpt-20b]