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).

Most new car manufacturers' e-SIMs are directly soldered onto the T-Box motherboard (surface-mounted) and cannot be removed and replaced like a phone. Unauthorized desoldering of the motherboard may cause complete communication failure in the vehicle, and we strictly prohibit this operation.

We will remove the chassis guard to physically inspect the battery pack's lower shell for serious dents or scratches, and check for signs of mud or sand intrusion in the waterproof vent at the edge of the battery pack.