**022120140098 Power Unit** is an industrial 220 V single‑phase hydraulic/electric power supply commonly used in lift and hoist systems. Common failure modes for this class include burned or tripped circuit breakers, failed solenoid valves, worn pump bearings, and degraded motor windings due to overheating. Begin diagnostics by verifying the incoming 220 V supply with a multimeter, checking all fuses and breaker status, inspecting the power unit’s internal wiring and connectors for corrosion or loose joints, and reviewing any error codes logged in the associated control panel. If voltage is present but no operation occurs, test the motor windings for continuity and resistance, then inspect the hydraulic pump for mechanical wear or leakage.[oss-gpt-20b]