Australian 7pin flat to American four pin flat (1 Viewer)

[googledave]

So I have a bj73 from NZ and it has the 7pin flat trailer and my trailer has a four pin. We’ll, I didn’t even look at what trailer plug until I needed to use the trailer… so the 7pin actually only has 5 wires :
Green-right
Yellow-left
Brown-marker
Black-earth
Red-brake/stop lamps
So my question is: how do I wire this to a 4-way plug? I called e-trailer and the nice guy in the phone couldn’t help me… I don’t care about keeping the 7pin plug-I actually want to replace it with a four way just have no idea how to get the brake lights working. Thanks again!

 

[sodafeld1]

Hah! Well trailer plugs in oz is a bit of a circus, we have 7 pin flat , 5 pin round, 7 pin round and some others and the shops sell about umpteen connectors for each way, male male, female female, female male etc... At least the packaging has what wires go where on some of them. But it depends on pvo, the bugger.

Best bet is use a test globe probe lamp and earth the alligator end. Touch the probe say with your green wire for example whilst your left indicator is flashing on your vehicle, if the probe flashs then that 's the one. Process of elimination. Use a brick on your pedal for your brake light.

Guessing from here red is power, black is earth, green left, yellow right, brown stop. But best do your test first.

Sometimes too, it is more effective to have the engine running so plenty of juice gets to the wires.

You will have to figure your trailer wires though.

 

[Hulsty]

Cant you just cut the plug off and wire to what ever one you want?

 

[googledave]

Cant you just cut the plug off and wire to what ever one you want?

Yes, but that’s the issue I’m having. So
I’ll do this:
Australian to USA
Green-right turn : Green-right and brake light
Yellow-left turn : yellow - left and brake light
Brown-marker: brown-marker
Black-ground: white-ground
Red-brake lights: no red wire on a USA 4 pin.

So that’s the question. How do I power the brake lights to my trailer. I want to use the four way just don’t know to wire the red(brake lights) I did use a rear light. And red does power brake lights when brakes applied

 

[Dougal]

Looks like US 4 pin runs left indicator/stop, right indicator/stop and tail/marker lights with an earth:

4 Pin Trailer Wiring Colors / Ks 5735 Landscape Trailer Wiring Diagram Schematic Wiring / I notice all the wiring kits require a hot wire ran to the battery.

Free Online Schematic

schematica4.blogspot.com

Pretty simple to rewire. But you won't have US style brake lights unless you try to combine brake and indicator. Might need diodes to stop back-feeding.

 

[googledave]

Looks like US 4 pin runs left indicator/stop, right indicator/stop and tail/marker lights with an earth:

4 Pin Trailer Wiring Colors / Ks 5735 Landscape Trailer Wiring Diagram Schematic Wiring / I notice all the wiring kits require a hot wire ran to the battery.

Free Online Schematic

schematica4.blogspot.com

Pretty simple to rewire. But you won't have US style brake lights unless you try to combine brake and indicator. Might need diodes to stop back-feeding.

Here’s a question: those cheap $20 Hopkins 3wire to 2 wire converters; will they work fine? Or do I need a 24v specific converter. Mind you, I’m not trying to step down voltage. I changed all my lights to led 10v-30v bulbs. When I called e-trailer they couldn’t help me. They didn’t even know about the 3wire to 2 wire converter..

 

[iliketrucks]

Here’s a question: those cheap $20 Hopkins 3wire to 2 wire converters; will they work fine? Or do I need a 24v specific converter. Mind you, I’m not trying to step down voltage. I changed all my lights to led 10v-30v bulbs. When I called e-trailer they couldn’t help me. They didn’t even know about the 3wire to 2 wire converter..

Funny to see this come up because I happen to be working through the same situation right now. So far I can find curt 56424 is advertised as for 24 volts, but it's out of stock almost everywhere I look.

I can't really find much information, if it comes down to it I'll just try whatever converter I can find and see what happens, it could be a month or so though.

Edit: my 3 to 2 wire converter wasn't advertised as being 24 volt compatible, but so far it is working

 

[Dougal]

Here’s a question: those cheap $20 Hopkins 3wire to 2 wire converters; will they work fine? Or do I need a 24v specific converter. Mind you, I’m not trying to step down voltage. I changed all my lights to led 10v-30v bulbs. When I called e-trailer they couldn’t help me. They didn’t even know about the 3wire to 2 wire converter..

Agreed. Put LED bulbs in your trailer and they won't give a damn if it's 24v or 12v. I have no idea what 2-3 wire converters are. I'm in the wrong country and never had to deal with them.

 

[45Dougal]

Maybe I misunderstood, but I think you're trying to wire an international truck with orange rear turn signals to an American trailer with only red stop lights?
If this is the case then you'll need diodes, otherwise when you hit the brake then your front turn signals will come on. I guess the bulbs are 21w each which is about 1A at 24V (2A at 12v).
The red brake line drives two bulbs, so that's a total of 2A at 24V, while the turn lines drive only one bulb.
A simple rectifier diode such as a 1N5408 should suffice. You'll need a higher current rating if you're running at 12V.
You'll need four of them as below - sorry for the rough sketch.

 

[beatle_bayly]

Generally, the 'reverse' wire is ignored (reverse lights are not compulsory on trailers in AU) and may be used as the 12V power feed wire, though the current capacity is limited.

 

[googledave]

All this info is fantastic!!! Thanks all for the help! So I bought a Hopkins 48847 3 to wire taillight converter and it worked perfectly for the short trip I’ve done with the trailer.. it cost $20. My trailer has combination lights and I’m running leds that are good from 10v-30v. My rig is a bj73 24v. I’ll keep everyone updated to see if this thing lasts…