How to Determine Trailer Wiring Functions for Installing New 7-Way Connector

Question:

Just got my trailer rewired, there are 4 wires, red, black, yellow and white. There is a 7 way on my truck and Im trying to figure out where the wires go on the male adapter to get the lights on the trailer to work with the lights on the truck.

asked by: Barb K

Expert Reply:

The colors that are used on your trailer are not the industry standard colors so you would need to test them to determine their function when wiring up a new connector for them.

One way is to use a jumper wire from a 12 volt battery to put current on each circuit to see what light functions illuminate. Or you can trace each of the wires to see where they go and determine it from there.

For a new 7-way to wire to the trailer we have the part # H20046. I attached a chart that details what each of it's wire functions are so that you can match your trailer wiring to it.

expert reply by: Jameson C