Link Technologies MC 70 (part 15‑102‑880‑001) is a color video terminal/monitor used on industrial control panels and CNC machines, typically interfaced via RS‑232 or parallel serial ports. Common failure modes for this class include power supply degradation (brown‑out of the backlight), failing LCD panel pixels, and connector corrosion leading to intermittent signal loss; internal logic board failures such as blown capacitors or damaged ICs are also frequent. First‑check steps: verify 12 V/5 V rail continuity and correct voltage at the terminal’s power connectors, inspect all serial/parallel cables for proper termination and secure contacts, and review any diagnostic LEDs or error codes displayed on the unit before proceeding to internal board inspection.[oss-gpt-20b]