Mainstream Chinese automakers rarely publish official English versions of their underlying circuit diagrams. We can provide some models' original Chinese technical documents (PDF) for B2B clients, which you will need to translate for your local mechanics using translation software.

For gasoline cars, insist on a compression test: each cylinder should read within 10-15% of the others, and the actual values should match factory specs for that engine. A single low cylinder points to worn rings or valve problems that idle checks will never reveal. A leak-down test goes further. It pressurizes each cylinder and measures how much air escapes and where. Air hissing from the oil filler cap means ring wear; from the intake or exhaust means valve issues; bubbles in the radiator coolant mean a head gasket problem. This is the single most revealing test for engine condition. Also request OBD scan data with freeze-frame records, a coolant system pressure test (to catch hidden leaks), and an inspection of the timing belt or chain condition with service history. For electric vehicles, compression tests don't apply — instead ask for a battery health report from the BMS, motor insulation readings, and a road test logging any inverter or drive-unit fault codes. A written report with photos or video of each test is essential evidence for your records.

Under FOB or CIF terms, all risks before crossing the ship's rail are borne by the seller (us). For minor scratches, we will provide a price discount based on the damage assessment; for serious damage, we will immediately terminate the vehicle delivery, refund the full amount, or replace it with a vehicle of equivalent configuration.