US Patent 9430884 Vehicle communication and cable tester system

A device includes a processor in communication with a first port, a second port and a third port. The first port is configured to communicate via a diagnostic cable with an electronic control unit of a vehicle. The diagnostic able cable has a first end configured to connect to a vehicle port and a second end configured to connect to the first port. The processor is configured to selectively test the communication capability of the diagnostic cable when the first end of the diagnostic cable is connected to the third port and the second end of the diagnostic cable is connected to the first port.