Does keeping an external device plugged into the car's OBD interface for a long time affect the car?

[LeJasper]

Under normal circumstances, keeping an external device plugged into the car's OBD interface for a long time does not have much impact, as the external device only reads data from the car's onboard computer via the OBD interface. However, risks still exist, and it is not recommended to keep external devices plugged in for extended periods. The role of the OBD interface: The OBD diagnostic interface connects to the serial data bus of the onboard computer. All sensors and communication devices on the onboard computer communicate via a single serial bus, and then a decoder is used to interpret this data. For example, data such as water temperature, vehicle speed, and fuel tank levels are transmitted from sensors as encoded data via the CAN bus to the onboard computer. The onboard computer can then decode and interpret the data. As long as the appropriate decoder and decoding software are available, any device connected to the bus system can recognize, send, and read data. Risks of plugging in external devices: If the external electronic product is of substandard quality—for instance, if it draws excessive power or poor quality leads to a short circuit—it can burn out the OBD interface. Additionally, if the standby current is too high, it can drain the car's battery, ultimately preventing the vehicle from starting.