This time, instead of doing all the wiring myself, I decided to buy the $50 wiring kit for my year and model from eTrailer.
In the kit is a 25 foot roll of flat formed 4 wire strip & colored cable and 2 snap in automotive bulb sockets, the bulbs with 2 filaments each and some wiring accessories. The bulbs are dual filament for running, turn signal, and brake lights all in one bulb. These sockets are meant to be inserted inside the car’s existing tail light cartridges. So you don’t need to do any splicing into the cars existing wiring. The systems are totally separate. You do need to drill 1″ diameter holes into the tail light plastic assembly wherever the tech (that’s me!) thinks it would work best…I chose the bottoms of the plastic shells so any heat from the bulbs would rise as this helps keep the socket and terminals in the socket cool giving them longer service life. Then you wire to the flat cable that comes from the connector. Here’s the drawing I created and then followed:
You can click on the drawing and it’ll open on a page with an expanded view, or you can right click and open it in a new tab then at the top of that page will be a link for an even larger view. Or you can hover your mouse cursor over the drawing and while holding the CTRL key on your keyboard, rotate the wheel on your mouse to expand the page.
Here is a picture of the 6-pin socket I bought on eBay shown screwed onto the Blue Ox base plate. The plate comes with two 1/4″ diameter threaded rods welded onto the base plate where you can screw on the 6-pin socket. They provide a couple screws for that too. I added a heavy wire in addition to the 4 wires in the flat cable so I could charge the battery while traveling. It’s powered from the corresponding circuit in the RV with wiring going to the battery (see drawing above). Reason for doing that is that I want to keep the battery topped off if I ever have to drive at night…with the charging circuit, I can run the car’s running lights for greater visibility of the car while on the freeway or arterial highways in the dark or low light situations and still have plenty of battery power to start it after a long drive. You’d be surprised how often people traveling the same direction in the other lane drift into a towed car as you pass them, because they often see the RV, but seem to miss seeing the car. Almost happened to me one time. I had to honk my big air horn to get their attention, caused them to wobble a bit. Not sure they even knew why I honked until I got up further ahead and then they noticed the car I was towing. So that’s why I install a simple charging circuit for the toad’s battery. With that I can leave the car’s running lights on (this in addition to the already on running lights in the tail light assemblies) and since today’s cars generally have running lights on the side panels, that makes the car much more visible at night.
Here’s the 6-pin socket all cinched up tight to the rods. Added a couple of flat washers behind the plastic ears to prevent deformation of the plastic. I dressed the wiring with zip ties after this picture so it wasn’t hanging down.
And here I separated and cut the white wire so I could ground it to the frame shortly after it enters the engine compartment, just for system safety reasons. A good ground is always important.
Here you can see how I routed the cable, and the extra red wire that goes to the fuse socket which has a 50 amp Schottky diode inserted where the fuse would go. The other end is fused. This diode protects both the car and RV. The diode is attached to the car’s battery and helps keep it charged while being towed and then via the wiring and umbilical to a fuse near the RV’s battery before being connected to it.
And then here’s where I store the cable when I’m not towing. It’s in a little cubby hole just forward of the drivers door and under the windshield, accessible when the hood is open, and covered when it’s closed. Nice and protected there. I may have to put the connector further inside the engine compartment when it’s raining to prevent water from soaking the connectors but here in the desert it’s fine where it is. It hasn’t rained so I’m not sure I even need to do that.
When I am towing, it’s a simple matter of routing the flat cable through the gaps in the door frame. Cable doesn’t get squished with the door closed so no damage to the insulation occurs.
And here’s the mating end of the cable coming from the trunk. It’s not in the way when I’m driving because I can just disconnect at the connector and position the cable out of the way. Even with everything connected, it’s still something that’s easily avoided when getting into, out of, or while driving the car.
I bought a kit of Molex 4-pin connectors to allow disconnecting and hiding the flat cable in the engine compartment and in the cabin. Reason was I didn’t want to have to find a place to route the cable through the firewall. It was looking like I’d need to drill a hole to snake the wires inside the cabin and I didn’t want to do that. I thought that just routing the wires through the seam in the door would work just as well.
As I have it set up now, when I’m towing, I’ll just snap together the two connectors of the 4-wire cable and drape the wire on the floor in the cabin. When I’m parked for a while, I’ll disconnect and hide the cable. I’ve already done this and it’s easy. Cost for the connectors was around $5 from eBay. I already have the crimping tool.
Then when I’m towing, I snake the flat cable through the car’s door seam. I fits fine, with no tendency for the car frame pieces to score the wire’s insulation even if I leave it there while I’m parked at some RV park for a few days and use the car several times. Then I route it down to the floor and run it along inside. I do have to try to miss catching my feet on it getting in and out of the drivers seat so in case I’ll be longer than a couple days at some park, I just disconnect it at the connector and roll it out of the way. No biggie.
When towing, I snap it into it’s mating connector. Eventually I’ll dress up this end of the wire cable by putting it underneath the plastic trim molding there in the picture with the connector exposed.
Because I seldom have riders in the car, I just routed the wires through the drop down rear seat so I didn’t need to drill any holes to access the trunk. Back in the trunk, I crimp the wires onto the previously installed pigtails that come from the bulb sockets following the wiring instructions that came with the bulb and wire kit. There’s no need, when using this extra bulb kit, to splice into the cars wiring to operate the turn signal, running, or brake lights as the 4-wire cable has everything needed to operate the new bulbs that are installed.
And on this side of the trunk, I used wire nuts ‘cus I was in a hurry. Soon I’ll crimp them like the other side.
So that’s it. That’s how simple it is to wire up most cars for towing using an auxiliary bulb kit from Blue Ox. As far as the bulb sockets that came with the wiring kit, I had to fully remove the tail light plastic lens assemblies, drill 1″ holes into the bottoms of them, and then snap in the socket and bulb. The wires that come out of that, are what is wired up to the 4-wire flat cable pictured above. The bulbs are in the same space as the original bulbs and just share the tail light assembly.
I thought I’d taken a few pictures of the tail light lens assemblies when I removed them and modified them to hold the new bulb and bulb socket but can’t seem to find them atm.