Adapter needed for plug

[iamunique127]

Now I have another related issue. Please tell me if I should start another thread for this.

On my Tundra tow vehicle the 7-pin plug is below the bumper on a plate with the 4-pin plugin right next to it. Like, immediately adjacent. So much so that only one access door will open at a time. If I plug in the 7-pin connector for the 5.0TA I can not open the door for the 4-pin connector I need to operate the lights on the trailer behind my 5.0TA that I will be watching with my new camera.

I've run a 4-pin wiring harness from the front of the 5.0TA, along the frame to the rear bumper. At the front, it drops down alongside the 7-pin wiring harness to the bumper but I can't fit both into their respective sockets.

I envision an adapter that plugs into the 7-pin with a Y coming out to a 7-pin on one side and a 4-pin on the other.

Does anyone know if such a beast exists? I've looked through Amazon.ca and found this one but I'd still have to adapt one of the 7-pins to a 4-pin:
https://www.amazon.ca/gp/product/B0B...2IYPUAG2&psc=1

Thanks for any input on this.

[Centex]

Originally Posted by iamunique127

....
I've run a 4-pin wiring harness from the front of the 5.0TA, along the frame to the rear bumper. At the front, it drops down alongside the 7-pin wiring harness to the bumper but I can't fit both into their respective sockets......

It sounds like your added 4-pin harness likely runs adjacent / past the umbilical cord OE junction box on the frame under the loft of your 5.0.

What about simply cutting the 4-pin harness from the back of the trailer at that point, routing it into the junction box, and using crimp ring connectors to add that harness' 4 wires to the appropriate lighting circuit studs in the OE junction box? Abandon the separate 4-pin cord to the truck.

The end result would be:

• Your OE standard 7-pin umbilical is all that plugs into the truck
• Your 4-pin connector on the back of the 5.0 would be 'hot' and ready for use whenever you plug-in the single 7-pin OE umbilical cord.
• That makes your 'wye' permanent, IMO moves it to a more convenient location, and eliminates extra pieces / plug-in connections which can be a source of problems like poor contact / conductivity (KISS)

Just for your consideration, Have Fun!

[iamunique127]

Absolutely Alan. I wasn't liking the adapter idea but doing what you suggested had not occurred to me. It keeps it simple and uncluttered. That's what I'll do.

Edited to say: I found the wiring diagram for the junction box so doing this should be straightforward.

Thanks for the excellent idea.

[BobG]

Originally Posted by iamunique127

... Edited to say: I found the wiring diagram for the junction box so doing this should be straightforward.

Thanks for the excellent idea.

Here is a picture of my opened splice box and the basic wiring diagram from Escape. Sounds like you already found the wiring diagrams. Good.

[iamunique127]

Ring connectors. Good.

My junction box is a 4" square metal box but I assume the connections inside will look similar.

Thanks Bob.

[iamunique127]

Now that I think about it, the square metal junction box may be 4" or 4 11/16". I'm not completely sure. I didn't look that closely at the box when I was there yesterday.

I'm also not completely sure how the umbilical cord is connected to the box. Is it a standard type fitting similar to this: https://www.homedepot.ca/product/ibe...in-/1000407930

It would have to be at least 1" given the size of that umbilical cord.

The trailer is stored about a 30 minute drive from my home so I like to be prepared when I go out there. Thanks for any input.

[BobG]

Originally Posted by iamunique127

Is it a standard type fitting similar to this: https://www.homedepot.ca/product/ibe...in-/1000407930

My box looks different than the description of yours so the knockouts might be different. Hopefully you will have a spare knockout for adding the 4-pin wire harness. I hope you don't have to replace your splice box with a larger one.

Bob

[occer]

Originally Posted by iamunique127

I'm also not completely sure how the umbilical cord is connected to the box. Is it a standard type fitting similar to this: https://www.homedepot.ca/product/ibe...in-/1000407930
Thanks for any input.

I prefer this type of fitting, water proof.

[Centex]

Originally Posted by iamunique127

Now that I think about it, the square metal junction box may be 4" or 4 11/16". I'm not completely sure. I didn't look that closely at the box when I was there yesterday.

I'm also not completely sure how the umbilical cord is connected to the box. Is it a standard type fitting similar to this: https://www.homedepot.ca/product/ibe...in-/1000407930

It would have to be at least 1" given the size of that umbilical cord.

The trailer is stored about a 30 minute drive from my home so I like to be prepared when I go out there. Thanks for any input.

Mine is the plastic box as pictured above, so yours is different. But, the concept for the 4-pin connection there should still be valid even if the mechanics are different.

You may need to take your time and make multiple trips to your stored trailer to do this job - a trip to open, study, and photograph your box situation, then another trip after collecting appropriate parts to make the connections.

Rather than guess, post photos of the box inside and out if you hit a wall and can't figure it out.

HINT - take a meter or continuity tester on your first trip to correlate the wires in the box to the pins of interest on your 7-pin connector

• ground
• taillights
• left turn
• right turn

[iamunique127]

Originally Posted by occer

I prefer this type of fitting, water proof.

Waterproof, of course. I probably would have seen that when I got to the trailer. I appreciate you mentioning it.

Do you have a suggestion on making a waterproof connection with only a 4-wire harness going into the connector? The first things that occur to me are building up the wire with tape to fill the gap or sealing around the wires with caulking. I have a part tube of the RV sealant.

I'll run over the Home Depot and check for that type of connector.

Thanks

[iamunique127]

Originally Posted by Centex

Mine is the plastic box as pictured above, so yours is different. But, the concept for the 4-pin connection there should still be valid even if the mechanics are different.

You may need to take your time and make multiple trips to your stored trailer to do this job - a trip to open, study, and photograph your box situation, then another trip after collecting appropriate parts to make the connections.

Rather than guess, post photos of the box inside and out if you hit a wall and can't figure it out.

HINT - take a meter or continuity tester on your first trip to correlate the wires in the box to the pins of interest on your 7-pin connector

• ground
• taillights
• left turn
• right turn

Thanks for that.

Looking at the wiring diagram it seems the colours of the 7-pin connectors correspond with the same colours for the 4-pin function-wise but I will check carefully.

I appreciate your input.

[occer]

Originally Posted by iamunique127

Waterproof, of course. I probably would have seen that when I got to the trailer. I appreciate you mentioning it.

Do you have a suggestion on making a waterproof connection with only a 4-wire harness going into the connector? The first things that occur to me are building up the wire with tape to fill the gap or sealing around the wires with caulking. I have a part tube of the RV sealant.

I'll run over the Home Depot and check for that type of connector.

Thanks

They come in different sizes and the package will have a range size. 1/2” will probably work for your needs.

[iamunique127]

Originally Posted by Centex

Mine is the plastic box as pictured above, so yours is different. But, the concept for the 4-pin connection there should still be valid even if the mechanics are different.

You may need to take your time and make multiple trips to your stored trailer to do this job - a trip to open, study, and photograph your box situation, then another trip after collecting appropriate parts to make the connections.

Rather than guess, post photos of the box inside and out if you hit a wall and can't figure it out.

HINT - take a meter or continuity tester on your first trip to correlate the wires in the box to the pins of interest on your 7-pin connector

• ground
• taillights
• left turn
• right turn

Hi Alan. I see what you are talking about now. The colours don't necessarily correspond between 7-pin and 4-pin harnesses.
I found this in post #54 of this thread from 2016: https://www.escapeforum.org/forums/f...tml#post145608

Originally Posted by Brian B-P

Confusion between green and brown in trailer wiring is common, because the colour code used for 4-pin flat connectors (and other styles following SAE standard J560) is not the same as the colour code established a few decades ago for the RV-style 7-pole blade connector. That means, for instance, that the combined right turn and stop wire in the 7-pin from tug to trailer should be brown, but the same function in the 4-pin at the back should be green.

• tail - brown in 4-pin, but green in 7-pin RV
• right turn / stop - green in 4-pin, but brown in 7-pin RV
• left turn / stop - yellow in 4-pin, but red in 7-pin RV
• ground - white in both

If the 7-pin is wired to the conventional pattern (still followed by Bargman, the traditional and probably original manufacturer of this connector), there will be colour changes in both left and right signals between the 7-pin and the 4-pin. Some manufacturers advocate following J560 colour coding even with the old 7-pin RV connector, so you can't reliably conclude anything from the insulation colour of wire attached to one of these connectors until you check it to determine what coding was used.

I'm glad I kept looking at other ppls experiences. This gives me a place to start.

[iamunique127]

Originally Posted by occer

They come in different sizes and the package will have a range size. 1/2” will probably work for your needs.

The one I found at Home Depot comes with different adapters for different sizes and shapes of cables. It looks like there is an adapter that will work for me.

Thanks

[iamunique127]

My junction box is very different from what you guys have. It is as I recalled, a deep 4" metal box.
As you can see, there are no busses or waterproofing, just a plain old household connector for the 7-pin cable, some sort of sheath for the split loom and then butt joints inside.
The biggest effort to waterproof the box was to put those connectors on the rearward facing side of the box.



But I had taken this 1/2" strain relief fitting with me and it is waterproof so I didn't worry about putting it on the front facing side of the box, right next to the screw holes. haha



So the 4 wires would fit the hole in the smallest adapter that came with the fitting I wrapped them very tightly with high-friction silicone tape which is meant for forming a waterproof seal.
https://www.leevalley.com/en-ca/shop...xoCVy8QAvD_BwE


Staying consistent with the OEM instal, I attached the 4-wire leads to the proper 7-wire leads with butt joints.
I went with the connection instructions given by Brian B-P that I quoted in post #13 of this thread. Those connections proved to work perfectly when I tested the 4-pin harness at the back of the trailer.




All buttoned up. It's almost like nothing ever happened, except now I have a functioning 4-pin harness at the rear bumper.


Thanks again for all the input.

[Centex]

Originally Posted by iamunique127

... It's almost like nothing ever happened, except now I have a functioning 4-pin harness at the rear bumper. ....

. . . .