Purpose of Lights on 7 to 4-Way Trailer Connector Adapter Part # 47345

Updated 04/24/2010 | Published 04/23/2010

Question:

Can you provide additional details of how one can use the lights in the 7 wire to 4 wire adaptor? Will is identify a fault in the trailer wiring? Will it identify if the trailer is not wired properly? If trailer is wire properly and the light does not reveal any problems, does that mean that the all the trailer lights will work properly at all proper locations?

asked by: Andrew J

Expert Reply:

The lights in the adapter will tell you that the vehicle itself is sending the proper signals for the directionals, running lights and brake lights. These lights are useful to eliminate the vehicle as being the cause of any wiring problems. It will not tell you of any trailer wiring issues.

If the lights in the adapter indicate that the signals coming out of the vehicle are all operating correctly, but the trailer lights are not working you will have to troubleshoot the trailer. To do this, start at the trailer connector. Make sure that it is not damaged in any way or corroded. You will have to trace each circuit back to the lamp(s) it controls. Make sure that the grounding point attachment where the white wire grounds to the trailer frame (usually on the trailer tongue) is secure and not corroded. Trace each circuit looking for pinched, broken, or frayed wires or missing or cracked wire insulation. Any missing insulation that would allow the copper wire conductor to come into contact with the trailer frame can cause a short circuit.

expert reply by: Mike L