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Trailer Wiring

A couple of questions as I too want to access the reverse wire for my boat trailer with surge brakes.

Is the wire yellow or yellow/black?

Why didn't you splice into the yellow on the other side of the connector?

Thanks
Paul

I think it was just solid yellow, see pic. This is the harness that goes toward the hitch. If you go back to feb 5 pics, the problem is this is the right wire but does not go further out to the hitch after this connector. So, just cut it here and splice in the blue wire that comes with the kit. One of the pics, you see I just plug this wire into the trailer 5th connection. The kit comes with a five connector, but would be more trouble to replace the 4 connector at the hitch.
So all I used outta the kit was the blue wire.
 

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FYI - for others planning to tow some. My current boat and trailer are almost 5000 pounds. I have launched and loaded several times. I have AWD and It performs better than my Tahoe that I traded in. My previous boat was about 8500 pounds and the Tahoe handled that well, however it was 2WD. I can feel the difference of the AWD launching and loading.
Your old 2WD Tahoe was RWD. Therefore while your new AWD Telluride does better, it’s possible that a FWD Telluride would still be better at launching and loading because of the weight of the engine over the front axle where the torque is. That’s likely what is giving you the help over the front axle more than the rear axle.
 
I think it was just solid yellow, see pic. This is the harness that goes toward the hitch. If you go back to feb 5 pics, the problem is this is the right wire but does not go further out to the hitch after this connector. So, just cut it here and splice in the blue wire that comes with the kit. One of the pics, you see I just plug this wire into the trailer 5th connection. The kit comes with a five connector, but would be more trouble to replace the 4 connector at the hitch.
So all I used outta the kit was the blue wire.


Thank you. Based on the wire diagram it's the yellow/black.

I looked at the male side of the connector that you tapped into, the connector actually has a pin that goes into the female side of the connector, but there's nothing there. I removed the small red plug on the female side. I will try to access through that port, might be a neat solution.

BTW, should I be reading 12 volts on this yellow/black wire when the car is in reverse?

Paul
 
A couple of questions as I too want to access the reverse wire for my boat trailer with surge brakes.

Is the wire yellow or yellow/black?

Why didn't you splice into the yellow on the other side of the connector?

Thanks
Paul
Yellow/Black wire.
I didn’t splice into the yellow because you have to splice into the YELLOW/BLACK wire.
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Your old 2WD Tahoe was RWD. Therefore while your new AWD Telluride does better, it’s possible that a FWD Telluride would still be better at launching and loading because of the weight of the engine over the front axle where the torque is. That’s likely what is giving you the help over the front axle more than the rear axle.
When you are at a boat ramp you are dealing with slippery and possibly uneven surfaces from algae/plants, oil and gas and all sorts of various debris. There is no way FWD would be superior in this situation. At the lake I work at they don’t even let the patrons launch their boats. The lake dudes use huge 4WD tractors with giant tires so can safely launch any size boat.
 
When you are at a boat ramp you are dealing with slippery and possibly uneven surfaces from algae/plants, oil and gas and all sorts of various debris. There is no way FWD would be superior in this situation. At the lake I work at they don’t even let the patrons launch their boats. The lake dudes use huge 4WD tractors with giant tires so can safely launch any size boat.
Understood, but I meant FWD would still do better than RWD if the weight is on the front and rear tires are in the water. The friction required is up front. I wasn’t implying that AWD would be bad.
 
This discussion has been about splicing into the yellow/black wire for backup lights, but looking at the diagram posted earlier wire 1 (white) is labeled “E/R Junction Block (Fuse - Trailer)”. There is also a 30-amp fuse labeled “Trailer” in the junction box under the hood. I’m guessing (would need to confirm) it’s wired to this white wire in the harness.

When wiring up a 7-pin connector has anyone spliced into this wire to get 12v power instead of running a new wire and fuse to the battery?
 
This discussion has been about splicing into the yellow/black wire for backup lights, but looking at the diagram posted earlier wire 1 (white) is labeled “E/R Junction Block (Fuse - Trailer)”. There is also a 30-amp fuse labeled “Trailer” in the junction box under the hood. I’m guessing (would need to confirm) it’s wired to this white wire in the harness.

When wiring up a 7-pin connector has anyone spliced into this wire to get 12v power instead of running a new wire and fuse to the battery?

I’m going to do this tomorrow when my 7 pin kit arrives, seems easier to do that splice than running a wire all the way to the battery.
30 amps will be meaty enough for my trailer brakes.
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I’m going to do this tomorrow when my 7 pin kit arrives, seems easier to do that splice than running a wire all the way to the battery.
30 amps will be meaty enough for my trailer brakes.
How did it work for you? I was thinking about trying this also.
 
How did it work for you? I was thinking about trying this also.
Worked perfectly, here’s my towing experience report btw

 
Since 1975, this hasn't been an issue. See this explanation from the FTC. There was a whole discussion on this issue in the forum - search Magnuson-Moss


Bottom line is that if you don't damage a part that is covered under warranty during installation of your aftermarket devices, then the manufacturer couldn't deny the warranty. Long term, it may be best to have something professionally installed if necessary so you have a paper trail. But, for towing, you need to make whatever modifications you need to tow safely - the Telluride even with the tow package isn't equipped out the door to handle towing 5,000 lb safely - despite Kia's ads. They know this.


Yea, that's a no, although your second paragraphs is exactly correct. Mag-Mo doesn't protect you from harming a component covered under warrranty. The question of "By tapping into the factory reverse wiring, could I void the warranty?" is "Yes, you could. If you overload the circuit you have no protection from Mag Mo. If you do not, no harm, not foul.".
 
Dumb question, but did you all remove the wheel and cover to access the harness?
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Ok thanks! (And now that I have an audience, more questions!)

Do I really have to cut the factory wire going into the harness? There’s no way to attach the wire to the corresponding pin on the trailer side?

I’m also trying to hook up to the 30 amp power to run/charge onboard accessories while driving. More wire splicing or is there a better way? I’m making my wife nervous just looking under her car ....
 
Dumb question, but did you all remove the wheel and cover to access the harness?

No not required, in the thread are some pics of the dust cover and wiring. this is pretty easy to do, the wiring kit makes it easy, but all I used outta it was the extra wire and the pics show that. So I use the stock 4 wire connector to the trailer and the extra wire for the trailer backup.
 

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I just took delivery of our 2021 EX Premium with factory installed towing package. The installed wiring has a 7-connector plug.

There was a box which contained the hitch ball mount and a bag with the installation instructions... and an extra electric brake power wiring harness. I'm assuming that the installation kit is generic for different kinds of installations and that since the car came equipped with a 7-connector plug, that I don't need this harness? In other words, the electric brake power is already provided through the 7-connector plug and was wired to the car appropriately as part of the factory installation?

Thanks.

Mike
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I just took delivery of our 2021 EX Premium with factory installed towing package. The installed wiring has a 7-connector plug.

There was a box which contained the hitch ball mount and a bag with the installation instructions... and an extra electric brake power wiring harness. I'm assuming that the installation kit is generic for different kinds of installations and that since the car came equipped with a 7-connector plug, that I don't need this harness? In other words, the electric brake power is already provided through the 7-connector plug and was wired to the car appropriately as part of the factory installation?

Thanks.

Mike
Yes, I believe that is a four-pin harness, in case your trailer only has that connector. Electric brakes should work with the 7-pin, but of course you want to test the trailer brakes to confirm.
 
I just took delivery of our 2021 EX Premium with factory installed towing package. The installed wiring has a 7-connector plug.

There was a box which contained the hitch ball mount and a bag with the installation instructions... and an extra electric brake power wiring harness. I'm assuming that the installation kit is generic for different kinds of installations and that since the car came equipped with a 7-connector plug, that I don't need this harness? In other words, the electric brake power is already provided through the 7-connector plug and was wired to the car appropriately as part of the factory installation?

Thanks.

Mike
I'm new around these parts but far from green. Is there a brake controller attached to the system? I have not heard of Kia, nor any other auto manufacturer having an integrated stock brake controller. If it came stock with the 7 pin that is great but I do not think that a brake controller is included.
 
No stock brake controller.
 
I'm new around these parts but far from green. Is there a brake controller attached to the system? I have not heard of Kia, nor any other auto manufacturer having an integrated stock brake controller. If it came stock with the 7 pin that is great but I do not think that a brake controller is included.
There are basically two types of brake controllers out there today. Wired or wireless.

Wired will use that harness and typically has a box that looks like a radar detector that must be mounted in the cab near the driver. There is one called the Redarc Tow Pro Elite that has a box that can be hidden but the controls are a small round looking dashboard knob. Regardless if you go this route you have to mount the brake controller somewhere.

Wireless is a newer technology that does not require any interior mounting so you would not use the extra wire harness. Examples are the Curt Echo BT Wireless which gets mounted by simply plugging it in-line with the 7-way round plug at the back and configuring it once with your phone. Or there is the Tekonsha Prodigy RF Wireless that also gets its power from the exterior 7-way round plug but it gets mounted on the trailer.

I presume that with the growing popularity of the non permanent options, Kia did this so you can choose. They probably didn’t connect that incab harness so you don’t have live wires dangling behind the dash that aren’t in use.


If you plan to tow without a brake and just a 4-pin you may need to get a ~$10 4-pin flat to 7-way round adapter.

 




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