Customer question: Which part should be repaired or replaced first?
English explanation
Do not choose a part only from the visible symptom. Start with the affected scope and the fault boundary. A single LED or small module defect is more likely to involve the module, driver or local ribbon. A regular row/column defect may involve data group, HUB, scan configuration or ribbon order. A complete cabinet may involve power input, receiver, local cascade or configuration. Several downstream cabinets may point upstream to a sending port, fiber, RJ45 or processor output. Use a layered test: source and processor, signal path, receiver configuration, cabinet internals and then controlled hardware substitution. Export the original RCFGX before replacing a receiver. Isolate power before touching modules, HUB boards, ribbon cables or power supplies. Use a known-good, same-model part and change only one item. If the fault moves with the part, that is evidence; if it stays in the original position, investigate the path or configuration. After replacement, repeat the original symptom test, color tests, grid and a short stability run. Keep the removed part and label the test location until the result is confirmed.
Service boundary
A remote engineer can narrow the likely layer, but physical repair and final electrical verification belong to qualified site or workshop personnel. —
