Patent attributes
A towing vehicle includes a towing control unit with circuitry to detect whether a light is connected to the electrical harness electrically coupling the vehicle to the trailer. The towing control unit may include lamp connectivity circuits for, for example, the left turn signal and the right turn signal. To determine whether the turn light is connected, the corresponding connectivity circuit periodically generates a test signal. Based on characteristics of a response signal to the test signal. The connectivity circuit determines whether the corresponding turn signal light of the trailer is connected based on a response to the test signal. The connectivity circuit may distinguished whether an incandescent-based turn signal light, a light emitting diode (LED)-based turn signal light, and an open circuit is sensed based on the characteristics of the response signal.
