Patent ID: 7339465

Claim:
A vehicle-to-trailer light connection verification tester having an electronics circuit which function in combination with a towing vehicle and a towed trailer, wherein the towing vehicle includes a receptacle (J 1 ) having a plurality of sockets that are each connected to a like plurality of rear facing lights, wherein the towed trailer includes a plug (P 2 ) having a like plurality of pins that are each connected to a like plurality of rear facing lights, wherein said electronics circuit having means for determining: a) if each of the plurality of lights connected on the towing vehicle are or not functioning, b) if each of the plurality of lights connected on the towed trailer are or not functioning, c) when there is a lighting problem, if the lighting problem is with the vehicle lighting circuit or with the trailer lighting circuit, d) a plug (P 1 ) that interfaces with the receptacle (J 1 ) on the vehicle and a receptacle (J 2 ) that interfaces with the plug (P 2 ) on the trailer, e) a loudspeaker (LS 1 ) having a positive (+) terminal and a negative (−), wherein the (−) terminal is connected to said plug (P 1 ), f) a three-position mode switch (S 1 ) that is connected between the positive (+) terminal on said switch (S 1 ) and said receptacle (J 2 ), wherein when said switch (S 1 ) is placed in: (1) a first position, the plurality of rear facing vehicle lights can each be tested, if a particular vehicle light is functioning, said loudspeaker (LS 1 ) produces an audible sound, conversely, if an audible sound is not produced, the particular vehicle light under test is not operational, (2) the second position the plurality of rear facing vehicle and trailer lights are removed from the test mode and placed in a normal operating mode, and (3) the third position the plurality of rear facing trailer lights can each be tested, if a particular trailer light is functioning, said loudspeaker (LS 1 ) produces an audible sound, conversely, if an audible sound is not produced, the particular trailer light under test is not operational.