An OBD scan is one of the most cost-effective tools in a remote pre-purchase inspection, but you need to know what it can and cannot tell you. What it reveals well: current and stored fault codes across the engine, transmission, ABS, airbag, and body modules. A car with dozens of cleared codes in multiple modules may have electrical problems or a history of tampering. It also shows readiness monitors — if all monitors show 「not ready」 on a car that claims to be freshly serviced, the codes were probably cleared recently to hide something. What it reveals with the right software: live data. You can watch engine idle stability, coolant temperature under load, transmission shift behavior, and battery cell voltages on EVs. Abnormal fuel trims or misfire counters can flag worn injectors or coils before any warning light appears. What it cannot do: prove real mileage (odometers can be corrected digitally), detect physical accident repairs, or judge paint and rust. Practical advice: ask your inspector for a full-system scan report with screenshots, not just a 「no codes」 verbal summary. For Chinese brands, make sure the tool supports their protocols — mainstream scanners cover BYD, Geely, and Chery well, but some small brands need brand-specific software.

In practice, returning an imported car is extremely difficult, so your protection must be built in before payment, not after. Once a used car has been exported, reversing the transaction involves re-export paperwork, duties, and freight costs that typically exceed any refund you'd recover. Most exporters' contracts treat the sale as final once the bill of lading is issued. What you can realistically do: 1. If the car differs materially from the contract (wrong VIN, undisclosed accident, tampered odometer), you have grounds for a claim. Document everything and negotiate a partial refund or repair credit—full refunds are rare. 2. If the seller committed outright fraud, you can pursue legal action in China or report to the platform, but cross-border enforcement is slow and costly. 3. Some exporters offer a short arrival warranty (usually 30-90 days) covering major mechanical failures. Claims require immediate notification, third-party inspection reports, and proof the damage existed at shipment. The practical takeaway: never rely on the possibility of a return. Spend the money on a thorough pre-shipment inspection and clear contract terms instead—it's far cheaper than a dispute.

Because it's not a one-time transaction. Only by ensuring compliance checks, improving after-sales service, and providing parts can a good reputation be established, leading to repeat purchases and long-term cooperation.