The Wohrle CB‑09/SK27‑303 (and related MC‑09/SK2L models) is a 10–12 inch industrial TFT monitor used as an operator interface for PLC and control systems. Common failures include loss of image or flickering due to backlight driver degradation, power supply voltage drop at the panel’s 24 VDC input, or loose/oxidized connector pins; older tube displays may fail from cathode discharge or transformer leakage. First‑check diagnostics: verify the 24 VDC supply with a multimeter and confirm continuity on all data and power connectors; visually inspect for burned traces or swollen capacitors on the panel board; if possible, swap in a known‑good replacement monitor to isolate the fault.[oss-gpt-20b]