Method of retrofitting a data communication system to a vehicle

A method of enabling an existing wire supplying DC current to an electrical load of a vehicle to serve as a clean line for transmission of a data signal without interference from electrical systems of the vehicle, the method comprising:

• identifying a first end and an opposing second end of the existing wire;
• cutting the existing wire at the first and second ends to separate the existing wire into a first section, an intermediate section, and a third section;
• inserting a first inductor in series with a proximal end of the intermediate section of the existing wire and inserting a second inductor in series with a distal end of the intermediate section of the existing wire, whereby the DC current supplied via the existing wire from the first section to the electrical load at the third section passes through the first and second inductors that are configured to prevent high frequency signals from passing through the intermediate section, in order to provide the clean line for transmission;
• and
• coupling a data transmitting unit between the third section and the distal end of the intermediate section, and coupling a receiving unit between the proximal end of the intermediate section and the first section to permit data transfer between the transmitting and receiving units using the intermediate section.