4S dealership records are directly connected to the manufacturer's database, making the data hard to tamper with and the most reliable, with original parts guaranteed; third-party repair shops usually are not connected, making their data unverifiable. Therefore, we only consider the connected records from 4S dealerships as valid historical documentation.

Yes. We will use a professional diagnostic tool to scan all vehicle systems, including the Engine Control Unit (ECU), Transmission Control Module (TCM), Anti-lock Braking System (ABS), and Airbag Module (SRS), and provide English screenshots of all current and historical Diagnostic Trouble Codes (DTCs).

We will use a megohmmeter (insulation resistance tester) to measure the insulation resistance of the high-voltage bus. If the resistance value is below the national safety standard, it indicates a risk of leakage, and the vehicle will be deemed unqualified.