Trailer warning, this could happen to you

[D&D]

I had replaced the pigtail on my 32 foot hydraulic dovetail trailer with this style plug. On a recent trip I lost all trailer brakes because the cheap plug's connectors became so loose that it allowed the plug to "tip" enough to disconnect the brake control wire.

I keep a roll of electrical tape in the trucks door pocket and use 2-3 wraps of tape on the plug once its seated.
The springs in the receptacle go bad too..

I had the trailer brakes come on fully while doing 60 MPH on the interstate because of a defective transmission control unit which controls the built in trailer brake controller on my Chevy 3500 HD. It made for an interesting few seconds and I had to disconnect the trailer brakes and drive home without them.

That probably tightened the sphincter

 

[D&D]

Replace a 7 pin rv plug on your trailer and use that color code. You'll be chasing your tail for hours.

I replace a couple of those plugs a week.

I can tell you that using the color code I provided for your trailer and plug into your truck, your trailer will work properly.

Red - left turn
Brown - right turn
Green - parking lights
White - ground
Blue - trailer brakes
Black - 12 volt battery charge
Yellow - auxiliary

These are the color code for the plug on your trailer.

The photo you posted is what's used for the receptacle for truck. Not the trailer.

Ah, no need to match color coding on truck and trailer, gotcha

 

[Dftodd]

Ah, no need to match color coding on truck and trailer, gotcha
View attachment 3820462

Go down and get you a 7 pin replacement plug and open it up and check how it's labeled. Then wire it based on the color code provided by E-trailer. You'll get a rude awakening when you test it out.

That color code you posted on that diagram from E-trailer is wrong

Plug placement might be correct. But you will encounter a huge gremlin since about 90% of the replacement 7 pin rv plugs are labeled for color.

Occasionally I'll have one labeled for use.

I don't know man.... I've only had 18 years replacing those plugs multiple times a week

 

[buckeyefarmer]

good you figured it out, that's a strange one to happen.

Never go by wire color...

 

[Dftodd]

Ah, no need to match color coding on truck and trailer, gotcha
View attachment 3820462

Here's what im talking about for the colors for a 7 pin rv plug.

Now compare ro the diagram you posted from e-trailer.

But if you look at the diagram i posted, They have the color code listed twice. One is wrong, the other is correct.

This is from a replacement rv trailer plug

 

[D&D]

Here's what im talking about for the colors for a 7 pin rv plug.

Now compare ro the diagram you posted from e-trailer.

But if you look at the diagram i posted, They have the color code listed twice. One is wrong, the other is correct.

This is from a replacement rv trailer plug View attachment 3822461

Color takes a back seat to function.

 

[Bob Gibson]

That's a good catch. Now why did only 2 of the 4 brakes lock up?

Maybe only the one axle had brakes?

 

[LouNY]

Difference is between Traditional and RV, pin outs are the same but the wire colors can mean different things.

 

[Dftodd]

Color takes a back seat to function.

I realize that. But if the RV plug is labeled by color, you need to know what that color actually does on that plug.

If you just match color for color like quite a few people do, you get a mess.

One light stays on all the time, the parking lights blink when you turn, your trailer brakes come on in time with the blinker, etc....

My whole point, was if you follow the color code that you posted from e trailer and just assume the placement plug is color coded correctly, your gonna be messing with it for hours trying to figure out what went wrong.


Most replacement plugs don't even come with a schematic to tell you what color does what. They are just labeled for the color.

 

[Dftodd]

Difference is between Traditional and RV, pin outs are the same but the wire colors can mean different things.
View attachment 3824489

The 7 way heavy duty is found on semis and large commercial trucks. Everyone that I get comes with the standard color code in the middle.

I haven't come across any that have the yellow and green as your turn signals in almost 20 years.