The KME 26S12M004/A is a 12‑inch industrial colour monitor originally built around a CRT display, now commonly upgraded to an LCD panel via plug‑and‑play conversion kits. Common failure points for this model include power supply board faults (over‑voltage or capacitor degradation), video interface issues (broken VGA/HDMI connections), and backlight driver failures that cause dimming or flicker. For first‑check diagnostics, verify the unit’s 12 V DC input is stable, inspect all cable connectors for corrosion or loose pins, and review any error codes displayed on the monitor’s OSD or via its serial interface. If the screen remains blank after power verification, test the video output with a known good source to isolate the display from the controller board.[oss-gpt-20b]