Videos are provided as a guide only. Refer to manufacturer
installation instructions and specs for complete information.
Quickly and easily install a 4-way trailer connector on your Toyota Tundra with this custom wiring harness. T-One connector plugs directly into existing wiring - no cutting, splicing or tapping required. Powered ModuLite reduces strain on wiring system.
This custom-fit T-One connector plugs into your Toyota Tundra's wiring harness, which is located at the rear, along the driver's-side frame rail. Once you've plugged in the tow harness connector, locate the gray connector between the truck's battery and the fender at the front of your vehicle. Plug in the fuse holder wiring harness. Then attach the ring terminal at the opposite end of the harness to the positive terminal on your truck's battery. Insert the included 10-amp fuse into the in-line fuse holder.
Once installation is complete, the 4-way flat connector will be stowed beneath your Toyota Tundra, near the trailer hitch. A mounting bracket (sold separately) is recommended to keep the connector secure.
It is recommended that you use a small amount of grease on all electrical connections - the plugs on your automobile and the 4-pole connector itself - to help prevent corrosion.
A ModuLite power module is built into this T-One connector. Because most trailers run on a two-wire system - wherein the brake and turn signals are carried on one wire - the separate brake and turn signals from your Toyota Tundra's three-wire system need to be combined so they are compatible with the wiring system of your trailer. This power module functions as a tail light converter to combine the brake and turn signal functions of your automobile so that they run on one wire to properly activate your trailer's tail lights. Note: This will not affect how the tail lights on your Toyota Tundra operate.
With a ModuLite, your trailer's lights will be powered without overloading your Toyota Tundra's electrical system. Because the module draws power directly from your car's battery and bypasses the electrical routes that are used by a basic wiring harness, there is virtually no draw on your tail light circuits.
Video of T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
Videos are provided as a guide only. Refer to manufacturer
installation instructions and specs for complete information.
All right today on this 2002 Toyota Tundra were going to install part number 118378 from Tow Ready. All right, the first thing we need to do is go ahead and install a fuse holder by the battery. All right, now therell be a gray connector between the battery and the fender. Well take the cap off, well install our wire harness. Now, in some vehicles you can see these connectors and some dont, so it may be a good idea to go ahead and move the battery out of the way to find it. And also, some vehicles have a connector already installed to the hot lead to the battery.
However, a wiring harness uses a higher amperage, you would have to remove it and install the new one. In this case its nonexistent so well go ahead and start fresh. Well remove the cap and then go ahead and connect it to a positive side of a battery. All right, well take a moment to use a couple of zip ties to secure the wire harness and then well go ahead and add our 10M fuse. Well put the cover on top of it and well move to the back of the vehicle.
Well locate the plug and install it there. Our connection point will be located behind the bumper just past the drivers side frame rail underneath the bed of the pick-up located right here. Well take the cap off and well install our wire harness. Well move away from it towards the center of the vehicle. Okay, well connect some of the sheet metal and attach our module with adhesive to a sheet metal.
Then well route our wire to the center of a vehicle to the license plate holder. And well take some zip ties to secure our wires. And with that that will finish it for our install of part number 118378 on our 2002 Toyota Tundra.
Average Customer Rating: 4.9 out of 5 stars (43 Customer Reviews)Quickly and easily install a 4-way trailer connector on your vehicle with this custom wiring harness. T-One connector plugs directly into existing wiring - no cutting, splicing or tapping required. Powered ModuLite reduces strain on wiring system.
by: Dan C06/20/2012
Needed this harness for my 2002 Tundra. The Tundra owners manual leads you to believe that the factory harness is ready to haul a trailer, but this is not accurate. I installed the T-One Vehicle Wiring Harness with 4 Pole Trailer Connector with no difficulty in about an hour (and that was taking my time!). Instructions were clear and had good photos. Product arrived faster than I expected, and customer support was quick to answer a question about which rear truck connector to use (it is NOT the connector just behind the license plate, but in my case over on the far left side behind the tail light). I will definitely shop at Etrailer again. 45011
by: Bob T08/29/2013
I've had a Hidden Hitch and wiring harness on my Toyota Tundra for a number of years. When I needed to get a 7 way plug I found that the old wiring didn't work. So I repmaced it and added a plug. The installation was easy and it works great. I wish there had been a single harness but replacing the old one and adding the 7 pin was very simple. I got great service from E-trailer and the video's were a good help. I'll use them again! 97496
The harnesses plugged right up and worked perfectly. Great product! Communication from eTrailer was the best. Package tracking was weak and did not provide enough info. The eTraller website is easy to use & provides great info & instructions on the produce installation. Because the instructions were so good the purchase decision was no-brainer. I definitely make eTrailer my first look for this kind of product. 53315
What can I say? This was the easiest install I've ever done. It literally took me 25 minutes to remove the old harness, then install and test this wiring harness and this is the first time I've installed anything like this. Etrailer responded to my online order within minutes and I had the kit delivered in 2 days. Great service, great product.......I'll be back in the future! Thank you etrailer. 38065
by: Mike K06/30/2015
The harness I ordered was installed on mu 2001 Tundra in ten minutes. Easy, excellent delivery time and completely satisfied. The boat goes to the lake tomorrow with every light on the trailer working. The videos were an excellent source for me. Reading instructions is not my strong suit. 208423
by: Matt in Upper Michigan09/18/2012
Had a positive experience with the wiring package I ordered through E-Trailer. Sales rep was knowledgable, friendly, and competent. Price and shipping costs were very fair.I received the package quicker than I expected and was happy to see the item was correct and exactely what i needed. 55094
by: Ridge W.11/22/2013
The T one wiring harness for my 01 tundra worked perfectly , I watched the installation video on the website and when it arrived it took less than ten minutes to install . E - trailer's description and customer service were excellent I highly recommend them and their products. 108228
by: Tom H10/08/2012
Received the product Friday afternoon and had it installed Saturday morning. Start to finish it took 20 minutes.I watched the on line vidio. Then followed the instuctions that were strait forward and clear. Very happy with the product! 56708
by: Roy C10/01/2012
++This is my second order from etrailer. Both products have been constructed with heavier wiring than is available from other sources. Shipping has been prompt & safe and installation has been relatively painless.++ 56201
by: Charles K. Childers06/20/2011
The T-0ne wiring harness was exactly as you described - a simple and easy plug-in installation. I am completely satisfied with my purchase as well as your highly efficient customer service. 17383
The product was just as ordered and delivered very fast. Setup was very simple (took 20 Min less if battery didn’t have to be moved) with normal hand tools. Would highly recommend 77785
by: joe j05/18/2013
The product was great with easy and understandable directions and helpful pictures. they let you know continually about your order progress. Yes I would use this company again. 80807
Very easy to install, perfect fit with the truck's existing connectors, good quality, and most important, worked flawlessly. I do recommend this product from etrailer.com. 158279
by: Danny Z08/02/2012
This product saved me somuch time and effort. Everything went together as it should. Excellent product and service. Never have I felt like such a valued customer. 50300
by: Mike D. Ohio10/19/2012
Very impressed with the product. Works as advertised; it took me about 15 minutes to install it. Works like a champ Thanks Etrailer.com saved me a lot of money 57639
The converter and the harness arrived in an easy-to-open packaging and with ample instructions. The device installed easily and worked as it was supposed to. 189717
by: Tom Snowman07/11/2013
I am extremely satisfied with the product and especially the seevice. I placed my order on a Saturday and it arrived Thursday; works great! Thanks again! 89027
by: Gregg K.05/09/2013
Had no issues installing this harness. May want to have a few extra zip ties available to satisfy individual tastes in the final dressing of the cables 79633
by: Ben W.12/13/2012
Got my order in a timely fashion. Quality product and easy to install! I appreciate the instructional video on your website for installation. Thanks! 61278
The product plunged into my original wiring harness and function as designed. The price was competitive and the service was excellent. 59170
by: harvey smith08/14/2014
I received the 118378 quicker than i thought. the product was very easy to install. i would reccomend the product to anyone. 146721
This harness was truly plug and go. Took me all of 20 minutes to install. Excellent design allowed for a very clean install. 146116
by: STEVE T10/22/2014
Excellent service, product and delivery time! Saved money , time and hassle, will use Etrailer.com again in the future! 157451
by: Steve B02/01/2014
The wiring harness was delivered promptly, fit the older truck perfectly, and worked perfectly. Very satisfied. 115380
by: Bob F03/21/2015
Shipping was much faster than expected. The part was exactly what I needed and works perfectly. 180093
by: Ted Y.12/21/2013
Great product, great service, great price. very helpful and easy installation thanks to video:) 110823
Received my order very quick. Plugged it I'm, ready to go. Thanks for the quick response. 144718
I received the wiring harness right away but haven't installed yet I hope soon but thanks 62856
This was so easy to install. And it works perfectly. Would recommend this to everyone. 42856
by: Steve W06/27/2012
I am very happy with the light assembly. Delivery was on time and everything works great! 45801
by: Jerry M.08/29/2011
Have yet to install converter box on truck, but appears to be correct on for vehicle. 23005
by: Chuck S05/11/2011
This wire harness was easy to install and fits perfectly. It works great 13600
by: chad f10/14/2013
shipped very quickly, staff was great, parts worked as supposed too !;) 103797
by: Andy B02/14/2011
Plugged right into factory harness. Instructions were good with pictures 7158
East to install. Just what the Dr. orde red 60753
by: r novak11/12/2014
item installed and performed excellent 160570
by: Jay J.08/01/2012
Easy to install, and worked first try. 50201
by: Dave A02/27/2012
Fit perfectly.Installed in minutes. 32671
by: Ed M.05/31/2012
Easy to install and it works.... 42128
by: Gary N06/25/2015
Good quality part, easy install 206996
by: Roy F08/25/2011
Great item VERY fast service 22804
by: Ivan O. Cruz03/21/2012
Great Buying !!!Nice 34591
by: Richard P.04/03/2011
A snap to install !! 10983
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