Patent ID: 8704650
Filing Date: 2014-04-22
Classification: B60Q,Y10S

Abstract:
1. A system comprising: a tractor having an ignition switch and an electrical load, a trailer having an electrical load, an electrical line between the tractor and the trailer and connecting the electrical load on the trailer with the electrical load in the tractor when the tractor is coupled to the trailer, a power source in the tractor to power the electrical load in the tractor through the ignition switch and connected to the line for powering electrical load in the trailer when the trailer is coupled to the tractor, a power arrangement in the trailer and having a given impedance, a test circuit including a test switch between the impedance and said line, said switch when on connecting said power source to said line, said test circuit, when the test switch is on, being responsive to when the power arrangement powers only the electrical load in the trailer and when the power arrangement powers both the electrical load in the trailer and the electrical load in the tractor.