Which method can be used to check if DEC control box ECMs have been swapped?

Using the "monitor" screen in YDIS (Yamaha Diagnostic Information System) is an effective method to check if DEC (Digital Electronic Control) box ECMs (Engine Control Modules) have been swapped. This screen allows technicians to view real-time data from the ECM, including parameters that can indicate whether the ECMs are functioning correctly and are the correct ones for the specific unit.

When examining live data through YDIS, discrepancies in the expected values, such as RPM, temperature readings, or throttle position, can suggest that ECMs have been swapped or are not communicating properly with the rest of the vehicle's systems. This data-driven approach aids in identifying compatibility and performance issues without relying solely on visual inspections or wiring checks, which may not highlight all potential problems.

Inspecting physical components and checking wiring connections are crucial in their own right but may not definitively confirm whether ECMs have been swapped. Similarly, performing a reset may temporarily clear issues but would not provide insights into whether the correct ECM is currently in use. Hence, utilizing the monitor function in YDIS is the most effective and reliable method for this specific verification.