The lifespan of rubber sealing strips for frameless doors is usually only 4-5 years. We carefully press the sealing strip at the edge of the roof to check for loss of elasticity and use a high-pressure water gun to wash the seams of the windows to check for direct water leakage due to aging.

The technician will start the vehicle and turn on the air conditioning system, measuring the actual temperature at the vents at the lowest and highest settings with a thermometer; at the same time, they will connect a manifold pressure gauge to check if the refrigerant pressure in the high and low pressure lines is within the normal range, determining if there is a chronic refrigerant leak.

Odometer fraud exists everywhere, but cross-checking several data points makes it hard to fake: 1) Maintenance records: ask for service history with mileage entries. Gaps or resets are red flags. 2) Tire wear: a car showing 30,000 km should not have nearly bald tires. Compare tread depth against the claimed mileage. 3) Pedals, steering wheel, and seat bolsters: heavy wear on these with low odometer readings is a classic mismatch. 4) Diagnostic scan: request an OBD readout. Many control modules store mileage data internally — if the ECU shows 120,000 km while the dash shows 40,000, you have your answer. 5) Vehicle history report: in China, apps and platforms can pull insurance claim records and registration history, which often reveal the true mileage trail. Always request a live video showing the odometer with the engine running, and have the number written into your contract.