For decades, excavator troubleshooting was relatively straightforward. If an excavator lost power, smoked excessively, overheated, or refused to start, the cause was usually mechanical. Mechanics focused on engines, hydraulic pumps, injectors, filters, hoses, and other physical components. Today, the situation is very different. Modern excavators contain dozens of sensors, electronic control units, wiring harnesses, displays, modules, relays, and sophisticated software system