The Bobcat S190 Main Frame Harness is the central wiring assembly that distributes power and signal between the loader’s control electronics, hydraulic pumps, and auxiliary systems. Common failures in this harness include frayed insulation on high‑current conductors, corroded terminal connections, and broken or miswired jumpers that can cause intermittent loss of hydraulic pressure or controller faults. For S190 units, watch for signs such as sudden drop in pump voltage, erratic sensor readings, or error codes related to the main frame bus. First‑check steps: verify the battery voltage and main power supply continuity; inspect all visible terminals for corrosion or loose contacts; review any diagnostic logs for short‑circuit or overcurrent events on the harness.[oss-gpt-20b]