Repair GuidesMindray DC and Resona Ultrasound Board Symptoms: A Decision Path for DC-70, DC-80, DC-8, DC-6/DC-60, Resona 7 and M7/M9 RepairsA structured diagnostic decision map for biomedical engineers, ISOs, and hospital service teams mapping no-image, probe-not-detected, channel dropout, 4D motor errors, and power failures to verified Mindray board assemblies and FDA 510(k) clearances across DC and Resona platforms.