This is how to make your own 3 wire trailer light + Ground converter to a 4 wire + Ground vehicle. Are you confused about how these
epoxy filled electronic converter are made ? I am shedding a little light on the subject here ( no pun in 10 did ). I also made a utube
of this, but for those instructables fans, here is how I wired my 2010 Honda Civic to a Harbor Freight utility trailer.
Step 1: This Converter Will Require a Pair of Radio Shack Relays
This project requires the purchase of a pair of Single Throw Double Pole relays, I used the Radio Shack Mini Relays
as they can handle 10 amps and are 12 volts. If you have a lot of trailer lights you will have to size the wire and relay
load to your need. This instructable is more of a how I did rather than a how to. I could not find any information
on the high price trailer light converter kits on the web, so this is how I think they work.
I have built this system on my new (at the time 2004 Honda Civic) and it has served me with no problem, to date.