We use two steps: 1. Insert a medical-grade endoscope through the spark plug hole to visually inspect cylinder wall scratches and carbon buildup on the piston top; 2. Extract an engine oil sample to check for large metal debris or emulsification (caused by coolant leakage).

The "usage type" section on the vehicle registration certificate has legal validity. Any vehicle that changes from "commercial" to "non-commercial" has a usage intensity far exceeding that of personal vehicles, and we will label these prominently. Such vehicles are usually cheaper but have more severe mechanical wear.

The method to deceive the dashboard warning light is to install a resistor. Our technicians will deeply read the real-time resistance values from the airbag control module (SRS Module) data stream and check for any non-factory stitching or adhesive marks on the steering wheel/passenger panel to uncover the disguise.