T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
(103 reviews)
Price: $64.20
In Stock
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
Item # 118378
Retail:$99.60
Our Price: $64.20
You Save: 36%
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- All Info
- Reviews (103)
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Tekonsha Custom Fit Vehicle Wiring - 118378
- Custom Fit
- Trailer Hitch Wiring
- 4 Flat
- Powered Converter
- Tekonsha
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.
Features:
- Provides a 4-way flat trailer connector at the back of your vehicle to power your trailer's signal lights
- Compatible with 5-pole, 6-pole and 7-pole adapters (sold separately)
- Connects quickly and easily - no cutting or splicing of wires
- Locate connection point along frame rail
- Plug in connector
- Plug in fuse holder under hood
- Includes ModuLite to ensure that your vehicle's wiring matches that of your trailer
- Powered module connects directly to battery to avoid overloading vehicle's electrical system
- Constructed of 16-gauge bonded wire
- Comes with dust cap for 4-way flat connector
Specs:
- Maximum amperage: 7.5 amps per circuit
- 1-Year limited warranty
Installation
This custom-fit T-One connector plugs into your vehicle'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 vehicle, 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.
ModuLite Powered Tail Light Converter
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 vehicle'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 vehicle operate.
With a ModuLite, your trailer's lights will be powered without overloading your vehicle'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.
118378 Tow Ready T-1 T-Connector - 4 Wire - Modu-Lite
Installation Details
This Product Fits The Following Vehicles
- 2001 - 2002 Toyota Tundra
- 2001 - 2002 Toyota Tundra excluding factory towable bumper
California residents: click here
Customer Satisfaction Score:
92% were satisfied with this product
8% of customers were not satisfied
- Wrong item was ordered
- Product did not meet expectations
- Alternate product found
Customer Reviews
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector - 118378
Average Customer Rating: 4.8 out of 5 stars (103 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: Daniel09/14/2023
I've had this for over a year in my Toyota Tundra that I don't treat very easy.
Still working great!
by: Cal 05/04/2024
2002 Toyota Tundra
Perfect fit for my older truck. Easy to install
by: Christopher 07/22/2023
2002 Toyota Tundra
Well made and plug and play for my 02 Tundra. It took 20 min to install. No cutting or splicing. I purchased along with a universal 7 pin kit for trailer brakes. It's perfectly compatible.
by: William D.09/04/2018
2002 Toyota Tundra
etrailer made the process quite simple. Online videos, written instructions, 2 day delivery all contributed to a painless process. '02 Tundra with 320k miles. Everything fit perfect.
by: TVillainX05/11/2019
2002 Toyota Tundra
This is the easiest trailer wiring kit that I've ever used. There was no drilling for a ground screw, no running a power wire the length of the vehicle, no disassembling the taillights. The Tundra already had the modular connectors, all we had to do was tap into them. The hardest part was deciding where to put the zip-ties. This is a great product and I highly recommend it.
by: Mike K06/30/2015
2001 Toyota Tundra
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.
Michael K.
6/29/2016
This product is working just fine. Makes me feel like a competent install mechanic.
by: Toby J10/15/2016
2002 Toyota Tundra
Was exactly as described. It took me less than 10 minutes to get the whole setup installed and tied up. The communication and shipping from ETrailer has be way above top notch. Highly recommend this company
Toby J.
10/15/2017
Haven’t had any issues. Still works same as Day I installed it
by: Bob T08/29/2013
Toyota Tundra
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!
by: Lane11/13/2021
I never got my wiring harnesses something must’ve happened when you guys sent it.
Jenny N.
12/1/2021
I will have our customer service team reach out to you.
by: Excellent product, fast shipping, even better cust04/18/2019
The product is exactly as advertised and arrived on time. Installed it and looks great.
Let me just start by saying that the product itself is not the most important thing. How many companies or sellers out there are reaching out to you and make sure that their product arrived on time and it met your expectations? And if not, following up and making sure they change that!? I am a big fan of etrailer and you have a great model going, keep up the good work and creativity to always stay a step ahead of the competitors.
BUYERS - Buy with confidence! You have nothing to lose when you are dealing with a seller that stands behind their product and customer satisfaction is their first priority!
Shoutout to Tommy C!
by: Ridge W.11/22/2013
2001 Toyota Tundra
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.
by: David 10/18/2022
2002 Toyota Tundra
Worked perfectly on 2002 Toyota Tundra.
by: Giris08/28/2012
2001 Toyota Tundra
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.
by: Thomas07/11/2020
My 2002 Toyota Tundra was not powering my boat trailer properly. After a bunch of testing the Tundra wiring I isolated the problem to the Toyota converter/power module. I found a replacement wiring harness at etrailer that matched my vehicle. I have received the new wiring harness and reviewed the installation instructions. Everything seemed to match up to my existing Toyota wiring harness which gives me a lot of confidence the installation will be a no-brainer. If I do have questions or problems I am confident the etrailer staff will be responsive and able to help me out. Although I do not expect that that will necessary. etrailer kept me informed throughout my purchase transaction from confirmation of my order through delivery. I will definitely use etrailer again.
by: Mike04/23/2012
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.
by: Dan C06/20/2012
2002 Toyota Tundra
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.
by: Russell T.02/19/2017
2002 Toyota Tundra
The trailer wire harness and mounting bracket for my 2002 toyota tundra came in on time and was easy to install. It took about 20 minutes from start to finish. I appreciate everything and will shop with etrailer in the future.
by: JimK09/17/2016
2002 Toyota Tundra
Works, Double sided tape came off - Used this one to replace same unit I bought 2 years before that died. If this one lasts only two years I will have one wired in.
Was very simple to wire in.
by: JAZ_Picayune10/28/2014
2002 Toyota Tundra
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.
by: John07/16/2021
I had to return the first harness, it was my mistake. The person on the phone was very understanding and found the exact trailer wiring harness I needed, it was an older vehicle, hooked up perfectly!!
by: Andy01/21/2017
This was an outstanding "plug and play" purchase. Etrailer continues to impress me with their DIY videos and ease of installation. This was a piece of cake to install. Continue the great work etrailer!!!
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.
by: Robert03/21/2023
Good quality
by: Tim04/21/2017
2001 Toyota Tundra
I had this installed on my truck 10 minutes after taking it out of the mailbox. The video tutorial was great. The hardest part was getting the cap of the plug next to the battery.
by: Jerry06/09/2019
Instructions easy to follow. Received exactly what I wanted and worked as advertised. Took about 15min to install. Would recommend to anyone needing a trailer light harness.
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Show More Reviews
See what our Experts say about this Tekonsha Custom Fit Vehicle Wiring
- How to Install a Brake Controller in a 2002 Toyota TundraI have a way for you to install either a P2 Brake Controller part # 90885 or a P3 # 90195 in your 2002 Toyota Tundra but there isn't a plug-in adapter available that would work. You will need to hardwire the controller in. Since you do not have a factory trailer wiring you will need to start with a 4-way (if you do not have one). For that you would want the # 118378. From there you would need to convert the 4-way to a 7-way so that you can install the brake controller. For that you will...
view full answer... - Parts Needed to Install a 7-Way Trailer Connector on a 2001 Toyota Tundra With Existing 4-WayYour best option is to install our Universal 7-Way and 4-Way Installation Kit, part # ETBC7. There are no plug-in style 7-way trailer connectors that will replace the Tow Ready harness on your truck, but the ETBC7 will use your existing 4-way and provide the additional hardware and wiring needed to have a fully functioning 7-way trailer connector. I attached an installation video on a 2002 Toyota Tundra to give you an idea of what will be involved with the installation. The installation...
view full answer... - Low Voltage From Converter 4-Way With Curt Harness on 2001 Toyota TundraIf you checked the wires right before the converter box of the Curt T-Connector Vehicle Wiring Harness # C55378 for your 2001 Toyota Tundra and got 12 volts, but then tested the wires coming out of the converter and got almost nothing, the issue will be a bad converter, which is rare but happens on occasion. I also do highly recommend going with a Tekonsha wiring harness for your 2001 Tundra, as they make the most reliable harnesses. The correct part for a 2001 Tundra is the Tekonsha T-One...
view full answer... - Recommended Wiring Harness for 2001 Toyota TundraFor your 2001 Toyota Tundra, I recommend the T-One Vehicle Wiring Harness # 118378. This T-One connector will plug directly into the port located under the vehicle, which is referenced in the picture that you sent. This will provide a 4-Way connector to hook up with your trailer and activate its rear signal lights. I have also attached an installation video on your 2001 Toyota Tundra that you can use for reference.
view full answer...
- Does the Tow Ready Harness # 118378 Ground Separately or Through the Converter Box HarnessThere isn't a dedicated ground wire that needs to be ran to install the # 118378 harness you referenced. It grounds through the connection that the harness with the converter box is attached to. You only need to make that connection and then connect the other included harness to the positive post on your battery and it will be fully functional. I attached installation instructions and an install video for more info.
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view full answer... - Trailer Light Not Working and Wiring Harness Show No Power on 2002 Toyota TundraFirst, what I recommend is checking the converter box in the trailer wiring, # 118378, to determine if it is the harness or the truck that is the problem. Use a circuit tester like # PTW2993 if needed to test the wires going into the converter box from the truck. If the signals are correct going into the box, you know that the truck is not the problem. Then test the wires coming out of the converter. If the signals are all correct coming out of the converter, the problem is somewhere...
view full answer... - Troubleshooting Installation of Curt 4-Pole Wiring Harness C55378 in 2002 Toyota TundraThe two wiring harness kits you referenced, Curt # C55378 and Tekonsha # 118378, are both correct fits for your 2002 Toyota Tundra. Both of these kits are multi-part harnesses that include the required fuse/fuse holder and the installation of the Curt kit in a 2002 Tundra is shown in the linked video. The troubleshooting steps I suggest are to double-check that all connectors have no bent or damaged contacts, that they are fully seated together and that the ring terminal on the harness...
view full answer...
- Is the Curt Converter Box for a 2002 Toyota Tundra Replaceable The converter box for the Curt T-Connector Vehicle Wiring Harness part # C55378 is not available as a separate replacement part unfortunately. However, I actually recommend you take a look at the T-One Vehicle Wiring Harness part # 118378 instead which we have found to be much more reliable. The issue that causes the converter boxes to fail is excessive movement. The above Curt converter box attaches using adhesive which is not always the best method. The Tekonsha converter box attaches...
view full answer... - Troubleshooting Brake and Turn Signals Not Working on Trailer I'm not sure which wiring harness you replaced but we can cover the trailer and the vehicle side for troubleshooting. The first thing I would check is your 4-way connection. Make sure both connectors are clean and free from debris, and make sure they are not damaged. Once this is done, I would go ahead and check out the connection on the vehicle side using a circuit tester like the # PTW2993. You want to test to see if the brake and turn functions are working properly on the vehicle connector....
view full answer... - Troubleshooting No Power From Converter Box on Reese Wiring Harness on 2002 Toyota TundraBased on the steps you have already taken it sounds like the converter box is bad which means it will need to be replaced, not opened and serviced. The only thing I'm not sure about is what wiring you specifically have. From what I could find it doesn't look like there is a plug and play 7-way for the 2002 Tundra. This leads me to believe that you have a 4-way wiring harness plugged into the factory port with a 7-way adapter added on. If that is the case, you only need to replace your...
view full answer... - 7-Way Trailer Wiring and Brake Controller Recommendations for a 2002 Toyota TundraTo install a 7-Way blade style trailer connector on your 2002 Toyota Tundra, there are a couple of parts you will need. First, you will start with installing a 4-Way wiring harness, # 118378. The tail light signals on your Tundra work on a 3-wire system. The converter takes those signals and converts them down to a 2-Wire system used by the trailer. I have included a link to the installation details for reference. Next, you will need to install a 4- and 7-Way Installation Kit, # ETBC7....
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view full answer... - Is The Rear Bumper On A 2002 Toyota Tundra Towable Yes, as long as you have 3 holes in the rear bumper on your 2002 Toyota Tundra (2 for safety chains and 1 for the hitch ball) they can be used for towing. You will also want to use a hitch ball like part # 19256 for 1-7/8", part # 19258 for 2", and part # 63840 for 2-5/16". According to your owner's manual, the bumper on your truck is rated up to 500 lbs. tongue weight (TW) and 5,000 lbs. gross trailer weight (GTW). As long as you are within this range, you can safely use the bumper to...
view full answer... - Brake Controller Installation for 2001 Toyota TundraSince your 2011 Forest River Rockwood Mini Lite Series M-1809S would have electric brakes and a 7-way trailer connector, you'll need to install a 7-way and a brake controller on your Tundra. The install isn't too complicated and we can walk you right through it. You'll begin by selecting a brake controller. I'd recommend a proportional controller like the Brake EVN # TK63VR and the # 20127 pigtail. A proportional controller will determine the intensity of the braking of the tow vehicle,...
view full answer... - Availability of Brake Controller Harness for 2001 Toyota TundraIf you are looking for a brake controller harness, there are none available for the 2001 Toyota Tundra. The 2001 Tundra did not have factory tow packages as an option, so a brake controller will have to be hard wired into the vehicle. You will need part # ETBC7 to create a 7 way plug at the rear of the truck. I will include a video on this kit. You will also need to install a 4 way connector. Toyota put the provision in for this so you will need part # 118378. Once you have these parts...
view full answer... - Transferring Prodigy P2 # 90885 Brake Controller from Ford Explorer to Toyota TundraSince trailer brake controllers are not vehicle-specific you can indeed transfer your Tekonsha Prodigy P2 # 90885 from your Ford Explorer to your 2001 Toyota Tundra. You will need the trailer brake install kit # ETBC7 that you referenced. If your Tundra does not already have a working 4-pole flat trailer connector at the rear bumper you will first need to install one. There are both hard-wire types (cutting and splicing required) and custom-fit plug-in types, which is what I suggest. You...
view full answer... - Solution to Install 7-Way and 4-Way on 2002 Toyota TundraThe only trailer wiring options we have for your 2002 Toyota Tundra is 4-ways like the part # 118378 which you could convert with a 7-way adapter like the part # 37185 which also happens to have a 4-way on the side of it like you wanted.
view full answer... - Brake Controller and 7-way Trailer Connector Installation on 2001 Toyota TundraThere isn't a plug and play option available for the 2001 Toyota Tundra, but you can certainly still install a brake controller and a 7-way trailer connector, and it's really not all that difficult. First, choose a brake controller. I'd recommend a proportional controller like the Tekonsha Primus, part # TK90160. A proportional controller is your best choice for safe, reliable and predictable braking. You'll also need our Brake Controller Installation Kit, part # ETBC7 and a # 118378 trailer...
view full answer... - 4-Way Trailer Wiring Harness for a 2002 Toyota TundraWiring harness # C55246 is not a confirmed fit for your 2002 Toyota Tundra but we do have wiring harnesses that will work. To add a 4-Way you can use # C55378, # 118378, or # HM43375. If it were me, I would go with # 118378 because it is the best value and we hear about fewer problems with the Tekonsha brand. I have linked a video showing an example installation for you.
view full answer... - Can You Give Detailed Step By Step Instructions For Brake Controller Install On 2001 Toyota TundraTo install a brake controller on your vehicle you will need Brake Controller 7 & 4 Way Installation Kit, part # ETBC7 and the Tow Ready Custom Fit Vehicle Wiring, part # 118378 on your 2001 Toyota Tundra. If your 2001 Toyota Tundra has an existing 4-way connector, you will not need to install part # 118378. For installation of part # 118378, start by disconnecting the negative terminal on the battery and remove the battery hold down bracket and slide the battery towards the motor. Next,...
view full answer... - Do I Need to Install a 4 Way Connector Before Installing a 7 Way ConnectorA 4 way connector like the Tekonsha # 118378 provides the base functionality and connections to the brake lights and turn signals, plus adding a converter box that are needed for a fully functioning 7 way connector. With that said, if you don't want to install the 4 way first, you could hard wire in a 7 way like the # HM40975-11998. Most people prefer the ease of installing a plug and play 4 way option in order to avoid any potential wiring issues, so it's usually the preferred method. If...
view full answer... - Truck/Trailer Brake Lights Come on with Trailer Connected and not Using Brakes, 2001 Toyota TundraFrom what I have been able to gather, the 2001 Toyota Tundra did not come with a tow package that included trailer wiring connections. This could mean that it was done aftermarket and could have been wired incorrectly by a previous owner. Or there could be a bad ground issue causing the malfunction. I recommend checking the ground connections on the truck and trailer side connectors. They will need to be clean and free of corrosion. I spoke with one of our installers about this problem....
view full answer...
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Tvillainx
5/12/2020
Still perfect - one year later!