I have an OBD2 hud display. It consists of the obd2 cable, and the device itself. Cable can disconnect from the device.
If I leave the cable plugged in, but the device is disconnected from it, does it still drain battery? The cable itself?
In other words, an open circuit. A cable that connects to OBD2 port, but the other end is not connected to anything (left hanging). Does it draw power?