The Stovebolt Site Forums The Parking Lot Big Bolts wiring for trailer

On my '54 6100, I am wiring it up for my trailer with electric brakes. I am running into an issue and was wondering which way most people go or if there is a different solution. On this truck, the brake lights and turn signals run thru the steering column (3 wires to the column, 1 to each turn signal and one to the brakes) and there are separate lights housing for the rear end. There are 4 on the back - left turn, right turn and 2 brakes. The wiring to the trailer is the brakes and turn signals are in the same light. So I either wire the truck up and the trailer matches the truck and can't be pulled by another vehicle or I put an add on clamp style turn signal for the the steering column instead of the factory one. Then I can match up wires correctly to the trailer. How has anyone else done this? Or is there some kind of adapter that people have used?

Was there a factory turn signal switch in 54?

To run trailer lights I think the best, or an easy, option is a 7 wire signal stat switch.

That is what I was thinking. Take off the factory one and replace with a 7 wire. I hate to do it but it is the easiest and cost effective solution.

My '57 2 ton has a three wire turn signal switch, old set-up had 4 lights at the rear, two were turn signals, the other two were stop/running lights. Since all the wiring and light sockets were trashed I converted to two tail lights that handle brake/turn/running. I built a circuit with two DPDT relays, each relay handles one side of the turn signal, when the signal switch is activated it closes the turn contacts and opens the brake contacts on one relay, the other relay in not affected. This allows standard trailer wiring.

where did you install or how did you install the DPDT? Where did you get it?

Can you share a wiring diagram of what you did? Sounds like this is the actual solution that I was hoping for.

If I am understanding DTDP Relays, It will take 2 in order for this to work. I am sure I don't show it correctly on the attached rough drawing.

I found the idea on the net somewhere but can't remember the site, I'll have to look at my wiring and draw a diagram but I gotta' 'git ready for church right now. Yes you need two DPDT relays - 12 volt of course. I had them on hand from other projects but they are nothing special. I also have my front fender mounted turn signals wired into the circuit, these are single filament bulbs and are turn only. Might be late today before I can get back to you, church activities and the farrier this afternoon. I'll add on now, I fabbed a mounting plate to attach under the dash and along with a 10 post terminal block screwed the plate to one of the supports left of the steering column, you'll need a good clean ground point. I didn't have to modify the turn signal switch and even the old blinker relay still works. I was lucky to find some new truck take off rear lights, Grote lighting from medium duty.

I am thinking this will work also.

Trailer Towing Converter

May work fine, may not be robust enough in the long run depending on the number and type of lights on whatever trailer you pull.

It's a new big Tex trailer. LED lights and only the stop/turn lights.

I don't know is this will help you out, but when I wired a car I built from scratch I wanted to use just 3 wires with a double-throw toggle switch. I bought a relay box from Ron Francis wiring that worked perfectly. Just a simple toggle switch, center off, with a left and right using just 3 wires. Remembering to turn them off is the only issue, like many other setups such as a motorcycle.

The Hoppy converter will not work, that was my first thought also and I wired it into my truck wiring to be able to run the two light system, no go.

kclark, are you sure the brake lights go through the turn signal switch, on my three wire switch it's one input from the blinker relay and one output to each side for the signals, I have no other info other than what I have learned from my truck. Brake lights were totally separate due to the turn signal being an option.

I'll take another look. But I'd still like to know more about your setup.

What was the result when you tried to use it? Did the whole thing not work? I know it has to be a 12 volt system instead of a 6 volt.

I have to find the schematic I drew up when I wired it, I know I found it on the net and was real excited about it so I copied the diagram by hand. I was going to cheat and use the Hoppy converter to accomplish the same thing within the wiring of the truck but it wouldn't pass enough current to run the system. My truck is a '57 so it's all 12 volt.

Ok kclark, go to H.A.M.B. the hokey [censored] message board, search turn signals, hemirambler posted a schematic for the circuit.

Thanks for the diagram, Just need to find the right relays. What kind of board did you attach them too?

I used some heavy gage sheet metal that would support the relays and a terminal block, it's about 3"x6", tucked under the dash so it's not visible unless you look up. The relays I used are ice cube style 1/4" sta-kon terminals. I'll see if I can get a part number for you.

Relay is OMRON MY2F -12DC, you'll need two.

Where's the best place to get those?

I found them at Grainger. I had to switch my search term around a little to find them.

But they are unavailable.

I service Generac automatic generators and had these in my used parts box, I see Radio Shack had a listing for them, I tried Summit Racing but nothing came up. Delcity, or a number of other on-line store have similar products. Just search for a 12 volt DPDT relay, the OMRON p/n I used has mounting ears, some don't.

The Ron Francis relay converter I mentioned earlier, although I didn't try to reverse engineer it, I did pull the cover off and remember it had 2 "ice cube" relays in it with a lot of wiring converting a 3 wire circuit into a 6 wire circuit. You could probably eventually figure it out, if you bought the right relays, but for $59 I decided that was cheaper.
http://www.ronfrancis.com/prodinfo.asp?number=SS%2D6

The link to the part didn't work, but here is a pic from an old catalog of the turn signal switch converter.

Google SS-6 Turn Signal Converter. Lots of choices🛠

Can these be mounted under the hood on the firewall? I was looking, and I was wrong, my brake wire doesn't come into the cab. I was thinking that since my turn signals and brake wires are all right there within inches of each other I could just mount the relays there.

I assume you brought extended your brake wires back into the cab. Did you cut your signal wires in the cab or under the hood and then bring them back thru the cab.

The relays should hold up ok under the hood as long as they stay dry. The wiring on mine was in pretty bad shape so I ran all new for the rear of the truck and grain box marker lights, I was able to keep the original wires from the turn signal switch and tied into them in the cab then brought the brake light wire through the firewall and connected into the relays. If your using the existing wiring then you may as well keep it all easy to get at under the hood. Since my truck had no terminal block for accessories I took the time to add that next to the relays. Mine is a Low Cab Forward and the only fuse is a 3 amp for instrument lights and two circuit breakers for the rest of the lighting - all on the light switch. I fed the new terminal block from the battery with a circuit breaker in line to protect all of my new wiring. My box markers are on a dedicated circuit, heated mirrors on another dedicated circuit, and an extra switch that I may use for back-up lights all with lighted toggle switches to remind me to turn them off.

Man, you need to show a picture of you setup and a diagram. I don't think I would ever do heated mirrors, but I can see doing backup lights down the road. I also like the idea of having circuit breakers.

I can't figure out how to post pictures, I got them loaded in my email but can't size them to put them in the forum. The heated mirrors were a bonus as I was shopping on Craiglist I found the stainless, lighted, heated west coast mirrors for $20.00, one was new in the box, the other had been mounted but in great shape. These things are about $300.00 new.

I'll send you a PM with my email and maybe you can forward those to me.

OK kc, I'll take pictures of my relay set-up and try to send them to you, I have pictures of the truck 'cuz I know folks want to see it, I'll try getting those to you also. I'm going to hit the hay now, I'll work on it tomorrow.

If I am reading things correctly on the relay, 1&4 are normally closed, 5&8 are normally open, 9 &12 are COM, 13 & 14 are Coil. With that, I think (correct me please) that the brake switch wire goes into #1, #5 will go out to the brake/turn signal light at the back of the truck and the turn signal wire from the steering column will go to #14 (coil +) and then coil #13 is grounded. Is that correct?

I can't find the schematic I drew up when I wired the relays so I'm going on the wiring from the truck. My turn signal switch wires are yellow=hot into the switch, light blue=out to the left relay #14, dark blue= out to the right relay #14, #13 from both will go to ground. I also tied in another yellow from the input constant hot and ran it to one side of the flasher relay. Coming out of the other side of the flasher relay run a wire to #5 and then daisy chain to #8, #5, #8 all N.O. Your brake switch should have a constant hot 'in' and switched wire 'out' to the lights, the wire that comes out of the switch will go to #1 and a jumper to the other #1 N.C. #9 on the left relay will go to the left brake/turn bulb, #9 on the right relay will go to the right brake/turn bulb. #12 on the left relay will go to the front left turn and left dash indicator bulbs. #12 on the right relay will go to the right front turn and right indicator bulbs. #4 is unused on both.

When you say flasher relay, are you talking about turn signal or hazard flasher relay that you added? From you picture, It look like you took the wire from said flasher relay and run it to your terminal block on the left and then from it you then went to 5&8 on both relays.

I don't have hazard (4 way) flashers, I refer to the thermal two post can as the flasher relay, not my add - on relays, it's not in view in the pictures.

Gotcha. I think I can get it going.

If you want to post any of the pictures I sent to you go ahead, you have my permission.