[cord4530]

I'm finishing my trailer hitch (U-haul copy). I'll have to update the drawing in the other post a tad now that I'm almost done.

But my question for those who have hitches is about the wiring for the trailer. I know I'll need a 6 to 4 wire converter, but do you know if the car requires a powered converter (has battery power running to it), or does a regular one work? I had an Audi years ago and the tail-light warning system would come on if you didn't use a powered one. Just curious if anyone had some insights on this.

 

[prsrcokr]

I'm not sure. The 4 pin portion of my Tacoma's harness plugged in series with the tail lights but included a small relay near the connector for the trailer. That plugged into the back of a 4/7 converter for the trailer brakes.

 

[cord4530]

Thanks prsrcokr. Looking back at my original pose, I should have been a little more specific....this is a hitch and wiring for a trailer on a MKIV Supra. I'm trying to figure out if I can get away with a simple converter like this:
Traditional Converter

Or if I need one with seperate power input like this:
Powered Converter

-Dan

 

[cord4530]

Well, I have answers to the question. I went ahead and purchased the non-powered converter and installed it on the car. I was pleased to find out that there were no warning lights telling me there was a problem with the tail lights. I towed a small trailer about 200 miles round trip. At the 1/2 way point I noticed the tail lights weren't working (on the car or trailer), and found that the fuse had blown. I replaced the fuse and all seemed well. Than about 50 miles from home I lost the tail lights again. I checked the fuse, but found it to be fine. Brake and turn still worked fine though, so I continued home in the dark with the flashers on.

Since the fuse was still fine, I went to the next component I thought could be off - the "Lamp Failure" module. (When I purchased the car, only the center brake light worked. I performed the fix from MKIV.com and all had been well until yesterday with the trailer.) I pulled the box last night and looked at it this morning. Here's what I found:
Image 1
Image 2

You can see in the center of the circuit board there are two jumper wires. One was totally fried, and the other is very near failure. My guess is that one is the tail lights, and the other the brake lights. So far as I know, both these jumpers were fine when I did the solder repair a few years back.

So, the moral of the story is that a "powered tail light converter" is what should probably be used for our cars. In all fairness though, the small trailer I was pulling did have several running lights, which would have added to the current draw on the tail light circuit. Either way, I'm going to replace my converter with a powered one before my next trip to the track.

-Dan