Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
(62 reviews)
Price: $54.48
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Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
Item # C56377
Retail:$83.25
Our Price: $54.48
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CURT Custom Fit Vehicle Wiring - C56377
- Custom Fit
- Trailer Hitch Wiring
- 4 Flat
- Powered Converter
- CURT
Quickly and easily install a 4-way trailer connector on your vehicle with this custom harness. T-connector plugs directly into existing wiring. Powered converter reduces strain on wiring system and is made using SMT to ensure superior performance.
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
- Locate connection points in rear cargo area
- Plug in T-connector
- Run hot lead to car battery
- Includes a tail light converter 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 using surface-mount technology (SMT) for consistent, reliable performance
- Maximizes trailer light yield and intensity while producing minimal heat
- Ensures superior operation in rough road conditions
- Comes with dust cap for 4-way flat connector
Specs:
- Maximum amperage:
- Stop/turn lights: 3 amps per circuit
- Tail lights: 6 amps per circuit
- Limited 1-year warranty
Installation
This custom-fit T-connector plugs into your vehicle's wiring harness, which is located in your rear cargo area. You will have to remove the floor coverings, storage trays, rear scuff panel, and side trim panel to access this harness. Once you've plugged in the T-connector, run the hot lead up to your car battery. Connect the lead to the included fuse holder, and then connect the fuse holder to the positive terminal on your battery.
Once installation is complete, the 4-way connector will be stowed in an out-of-the-way location within your rear cargo area.
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.
Powered Tail Light Converter with Surface-Mount Technology
A tail light converter is built into this T-connector. This converter is a circuit-protected, battery-powered unit that bypasses the electrical routes that are used by a basic wiring harness. As a result, there is virtually no draw on your tail light circuits.
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 the trailer. This converter combines 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.
Curt builds each tail light converter using surface-mount technology (SMT). This method of construction involves soldering electronic components directly to the surface of a printed circuit board. SMT eliminates the need for leads, which are used in older through-hole technology. The result is a circuit board that is smaller yet provides more routing area and that offers superior performance, reliability and durability.
Circuit boards constructed using SMT have been shown to perform better under rough conditions with excessive vibration than those made using the through-hole method. And where would vibration be more likely to occur than in towing applications? Curt converters also produce less heat, leading to increased durability and longer life. In addition, lower levels of resistance ensure better performance, especially for parts that operate at higher frequencies.
Each Curt circuit board is made using high-quality components that are pieced together in the most technologically savvy fashion, leading to greater predictability and reliability in functioning.
56377 CURT T-Connector Vehicle Wiring Harness with 4 Pole Trailer Connector
Installation Details
This Product Fits The Following Vehicles
- 2017 - 2021 Mazda CX-5
- 2017 - 2021 Mazda CX-5
- 2019 - 2019 Mazda CX-5 excluding Diesel
California residents: click here
Customer Reviews
Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector - C56377
Average Customer Rating: 4.8 out of 5 stars (62 Customer Reviews)
Quickly and easily install a 4-way trailer connector on your vehicle with this custom harness. T-connector plugs directly into existing wiring. Powered converter reduces strain on wiring system and is made using SMT to ensure superior performance.by: Curtis05/23/2022
Well thought out set up. A dream installation with the plug and play wiring harnesses. Took my time (especially when popping the back panels on my wife’s brand new vehicle) and still only took a couple hours start to finish. Definitely recommend this product.
by: Bruce04/03/2022
This install went well and was truly plug-and-play. I elected to tap power off the 12v jack in the rear luggage compartment rather than run a dedicated line all the way up to the battery. (I never use that jack anyway.)
by: Tom10/22/2021
This was very easy to install with minimal problems. Also purchased wire harness and install also was mighty easy. Since install, I pulled three trailer loaded with around 2K lbs of pavers to my house with no problem. Very Happy.
by: Maximus06/20/2022
2021 Mazda CX-5
Good Product, does what you need. It is time consuming...
Do Not like the fact they want you to hang the plug wires out the tail gate to plug in you trailer. There is a large grommet on the driver side that could be modified to get a good drop to the hitch. I split it and run the wires through then once it was back in place I siliconed it up.
by: Zach S05/07/2022
2022 Mazda CX-5
Good product easy install. Only hard part was running the wire under the car to the battery. If the car was on a lift would’ve been much easier!
by: Shannon 09/29/2021
Mazda
Works perfect for my 2018 Mazda CX-5 easy to install for the first time ever!
by: Kenneth08/23/2021
excellent service and prices,I ordered a hitch, but the wrong wiring kit. after looking again i saw a alert that the wiring kit ordered was not certified for my car.as this was the next day and my order had already shipped I called and after a brief wait, spoke to adam
he checked my order and confirmed, i had ordered wrong wiring kit.HE WENT OUT OF HIS WAY TO SHIP THE CORRECT KIT THE SAME AFTERNOON. he also e mailed a return label for my incorrect order. cant say enough about the good service and quality staff they have employed there...
by: Jeff 11/10/2021
2021 Mazda CX-5
great products, easy installation. the installation videos are great also
by: Scott07/14/2018
Mazda
Everything is easy to install except the line to the battery, and that just takes patience. I ended up temporarily removing the driver’s side protectors for an easier and cleaner run up my 2018 Mazda CX-5.
Comments
One year out and Im still very pleased!
Scott - 07/14/2019by: Chris03/20/2022
This kit was easy to hook up in my CX-5, and I found the instruction video especially helpful.
by: Thomas 09/30/2021
2021 Mazda CX-5
I'm sure the product will work just fine. I just wish your shipping dept. had put my name on the package instead of no name at all. The box made its way around our company with at least ten people looking at it, not knowing who it was for. There was not even an invoice inside the box, that might have had my name on it. It took a couple days but eventually I found it.
by: Bud 01/25/2021
The wiring harness I bought for my new hitch receiver fit my new 2020 CX-5 perfectly. Installation was easy, after figuring out how to disassemble the rear end of the SUV. The provided connectors mated perfectly with the vehicle connectors. Running a primary wire from the rear of the car to the battery was a bit of a pain; I'd recommend Curt find a way to tap into an appropriate conductor where the harness is being installed on future versions. Otherwise, everything worked perfectly, and when I got the car put back together the entire installation was invisible with the trailer connector pigtail stored in the spare tire compartment until needed. I'm completely satisfied with this harness, and recommend it highly.
by: Joseph02/07/2022
Volvo Cross Country
Used it for a cross country move and it worked perfectly. Install was easy, and the directions were helpful.
by: Kevin08/07/2018
2018 Mazda CX-5
Not a bad install, it was kind of fun. But, in the video I watched they failed to mention the hardest part: running a 12ga, 12V wire from the battery to the rear of the car. It was a little scary drilling a hole in a brand new car's firewall to get the wire through (I did not want to run it under the car, that seemed much sketchier than running it through the interior.) But I hooked it all up, connected my trailer, and, perfect: all lights work great.
by: Bill G11/21/2021
2021 Mazda CX-5
Perfect fit and easy install, all aided by excellent how-to video
by: David02/14/2019
2019 Mazda CX-5
Same as trailer hitch. Best for all my needs new car so added wire harness
by: Lynn02/23/2019
Mazda
I have not installed yet, but I installed another harness on my 2016 Mazda and it worked extremely well. I am sure this will work just as well. Shipping was fast and easy. Great company, price and product. Will definitely buy again when I need to.
by: William 07/10/2020
2020 Mazda CX-5
I installed this wiring harness myself on my 2020 Mazda CX-5. The instructional video was REALLY helpful. It showed in detail how to remove the interior panels to gain access to both taillights. The plug in T-Connectors were a snap to plug in. I chose to run the wire to the battery beneath the vehicle but inside the under sound proof panels so the wire is almost completely hidden from the elements. Works great and I would highly recommend this wire harness for a 2020 Mazda CX-5 (I think it works for earlier models as well)
by: Philip11/30/2020
I got it in 3 days of placing the order that was fast. the online installation instructions were great for both the wiring harness and the hitch. this is a good company to buy from 5 stares. thank you
by: Jorge05/20/2018
2017 Mazda CX-5
I am returning this because it is supposed to be plug and done. Well, I had to route a wire from the battery to the back of the vehicle. I found another one that doesn't require that step and draws power from the back junction box. Easier.
by: Jeff07/23/2020
2020 Mazda CX-5
Purchased a Class III Hitch Receiver and wire harness for a 2020 Mazda CX5. Arrived within a couple of days, was well packaged and complete. Hitch installed fine and planning to install wire harness this weekend.
by: Michael09/28/2020
Easy install. Watched the videos and removing the panels was easy. Ran the wire up to the batter without problem under the car, under the protective covers. Its tucked up nicely and I know it will not get caught or damaged on anything.
by: Edward 11/01/2021
2021 Mazda CX-5
Everything showed up super fast and in good condition, would definitely order from them again
by: Josh 10/03/2021
fit good. no problems
by: GordoC07/08/2019
Excellent product, easy installation on a 2018 Mazda CX-5 except for the hassle overcoming snaking the source wire through Mazda's difficult undercarriage. Worked perfectly after completed.
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Ask the Experts about this CURT Custom Fit Vehicle Wiring
- Does Wiring Harness on 2019 Mazda CX-5 Have to Get Power From 12V BatteryThe Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # C56377 will always be connected to a battery so it will be "on" in the same way that everything else that is connected to the battery of your 2019 Mazda CX-5 is "on." That said, there are no negative effects, problems, or issues whatsoever with it being connected to your Mazda's battery. The only problems that will arise are from attempting to power the connector from anything but a direct hot lead to the...
view full answer... - Does Curt Trailer Wiring Harness # C56377 Have Label On ItThe Curt harness part # C56377 does not have a label on it. Thank you for the picture but what you have is correct! I checked your order notes and you received the correct harness too.
view full answer...
- Options for Running Power Wire of Curt Trailer Wiring Harness # C56377The connection to the battery is something that many people have reservations about until they actually start the process and realize that it is not so bad. There are different ways you can get to the battery and we actually wrote an FAQ article on this topic which I have linked for you. The FAQ gives general tips on different methods for routing the power wire. You can run the wire through the vehicle if you wish but just keep in mind that this does take more time and you may end up...
view full answer... - Troubleshooting 3rd Brake Light Not Working on 2019 Mazda CX-5 After Installing Curt T-ConnectorYou might want to go back through and trace the steps that you took when installing the Curt T-Connector # C56377 on your 2019 Mazda CX-5 to see if you accidentally forgot to plug something in or if maybe some wiring got damaged. Since the tail lights are working properly I don't see how the T-Connector would be affecting the 3rd brake light but if everything looks fine you might as well disconnect the tees from the Curt wiring harness and plug everything in like it was prior to installation...
view full answer... - Does Curt Trailer Wiring for 2020 Mazda CX-5 have to Wire to Vehicle BatteryWe can't recommend you use any power source for installing the Curt # C56377 other than the positive post of the battery. This allows you to completely bypass the wiring of the vehicle so that in the event of a trailer wiring short it doesn't hurt the vehicle wiring.
view full answer... - The Lights On My 2018 Mazda CX-5 GT Alternate With The Trailer Tail Lights When Pressing The BrakeWhat you are experiencing is normal for your Curt T-Connector # C56377 on your 2018 Mazda CX-5 GT. The powered converter is taking the input from your vehicle lighting and distributing it out to the trailer tail lights. It may seem odd but there is no reason to be concerned as the lights are all working properly.
view full answer... - Wiring Harness Installation Instructions for a 2022 Mazda CX-5The Curt Wiring Harness with 4-Pole Flat Trailer Connector item # C56377 for the 2022 Mazda CX-5 attaches behind the rear tail lights. You will have to take apart your cargo area to remove the trim pieces to access the tail lights. The T-one harness plugs in line with the tail light harness so you won't have to cut or splice any wires. I have linked a video that shows the entire installation process including the removal of all cargo area trim to access the tail lights.
view full answer... - Is There Parasitic Battery Drain For Curt Wiring Harness C56377No, there is not a risk of parasitic battery drain for the Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector # C56377.
view full answer... - Can Wiring Harness be Installed After Hitch on 2017 Mazda CX-5?To answer your first question, yes, you would be able to install wiring after you have put in Draw-Tite # 76138. In regards to your second question, the answer is it depends on the harness. For example, Curt T-Connector # C56377 is a confirmed fit for your 2017 Mazda CX-5, and it could be installed without drilling.
view full answer... - Recommended Trailer Wiring Harness for 2019 Mazda CX-5Curt and Tekonsha both offer wiring harnesses for your CX-5. The Tekonsha model is # 118746 and the Curt is # C56377. Both install in the same manner, by plugging inline between the vehicle's taillight assemblies and the wiring harness that feeds them. No cutting or splicing required. Because the Tekonsha # 118746 has a higher amperage rating 5 amps/each stop/turn circuit and 7 amps/each taillight circuit as opposed to 3 amp/6 amps for the Curt model, I'd recommend the Tekonsha. Aside...
view full answer... - How to Install a Trailer Wiring Harness on a 2017 Mazda CX-5We have not yet had the chance to install a trailer wiring harness on a 2017 Mazda CX-5 so I would not have any additional advice for you outside of what is laid out in the instruction manual. However, I see you purchased the T-One Vehicle Wiring Harness part # 118746 which means you would have received the instructions included with this kit which I agree are rather vague. However, the process to install the trailer wiring harness will be the same as the Curt T-Connector Vehicle Wiring...
view full answer... - Why Does Trailer Wiring Harness for 2017 Mazda CX-5 Require Running Wire to BatteryNot all vehicles can handle the additional amperage draw of the trailer taillights on the vehicle taillight circuits. Those vehicles need setup that draws power from the battery. Some vehicles have higher rated circuits that can handle this, and others need to have the power drawn straight from the battery to protect the taillight circuits. For your 2017 Mazda CX-5 you need to install a harness that draws power from the battery to protect the taillight circuits. For that you would need...
view full answer... - Trailer Wiring Comparison for 2017 Mazda CX-5 Tekonsha Compared to CurtFor your 2017 Mazda CX-5 we have two trailer wiring harnesses available. The Curt part # C56377 and the Tekonsha part # 118746 which you mentioned. In general the Tekonsha kits are more reliable and less likely to short out. Partially due to the fact the Tekonsha has a higher amperage rating: # 118746 Stop/turn lights: 5 amps per circuit Tail lights: 7.5 amps per circuit Compared to # C56377 Stop/turn lights: 3 amps per circuit Tail lights: 6 amps per circuit
view full answer... - Can the Rear Accessory Socket on a 2017 Mazda CX-5 be Used to Power the T-One # 118746Although the recent CX-5s may have a power source bus in the hatch area you will want to run the wire for power to the battery. The Tekonsha T-One # 118746 is a new kit for 2017+ Mazda CX-5s which Tekonsha designed specifically for your vehicle. Since both Tekonsha and Curt (for the Kit # C56377) say that you need to route the power wire directly to the battery that is the best route to go. After routing the wire up to the battery you need to install the included fuse and connect it to...
view full answer... - Trailer Wiring Comparison for 2019 Mazda CX-5 Curt or TekonshaFor your 2019 Mazda CX-5 we have two trailer wiring harnesses...the Tekonsha kit part # 118746 that I recommend and the Curt # C56377 which is also a solid choice, but the Tekonsha is the better route. The reason I recommend the Tekonsha is because it will be more resistant to internal shorts of the converter box due to shorts on the trailer's wiring. This is mainly due to the higher amperage rating of the converter box (7.5/5 amps compared to 6/3 amps of the Curt) and because in general...
view full answer... - If asked to choose between the Tekonsha # 118746 or a Curt # C56377 I'd go with the Tekonsha. The Tekonsha model has a higher amperage rating, and over the years we've found their electrical products to be slightly more reliable in the long run than those from Curt. Curt makes a great product, but the Tekonsha is just a little bit better. If you click the provided link, you can see the harness I recommended being installed on a 2017 CX-5. The procedure on your vehicle would be identical.
view full answer... - Comparing Tekonsha and Curt Trailer Wiring Harnesses for 2019 Mazda CX-5Both the Tekonsha T-One Vehicle Wiring Harness # 118746 and the Curt T-Connector # C56377 are designed to fit your 2019 Mazda CX-5, and will install in the same manner by plugging into existing ports behind the trim panels in the vehicle's rear cargo area. Both also require a hot lead to be run up to the battery for power. Between the two options though I do recommend the Tekonsha T-One # 118746 because it features a higher amp capacity for its circuits and also uses a superior converter...
view full answer... - Easy to Install Trailer Wiring Harness for 2020 Mazda CX-5I checked with Curt and they just recently confirmed the fit of their trailer wiring harness # C56377 for your 2020 Mazda CX-5. This is a custom install kit so the install would be super easy as well!
view full answer... - Trailer Wiring Harness Recommendation 2020 Mazda CX-5Tekonsha and Curt both offer trailer wiring harnesses for your vehicle. Between the Curt # C56377 and the Tekonsha # 118746, I'd suggest the Tekonsha, as it has a higher amperage rating at a pretty similar price. If you click the provided link, you can see a video of the harness being installed.
view full answer... - Difference Between Wiring Harnesses for 2019 Mazda CX-5Between the two wiring harnesses that fit your 2019 Mazda CX-5, Tekonsha # 118746 and Curt # C56377, I recommend the Tekonsha. It has a higher maximum amperage than the Curt. Another reason I recommend the Tekonsha is simply because we've always had better success with their reliability. I also prefer how the Tekonsha's converter box actually uses a screw to anchor it in place where the Curt's is just doublesided tape.
view full answer... - Trailer Wiring Install Harness that Fits 2021 Mazda CX-5Tekonsha has a trailer wiring harness that fits your 2021 Mazda CX-5 with the part # 118746 but the one you did try would not work as it was not designed to fit it. I attached an install video for this harness on a similar 2021 Mazda CX-5 for you to check out as well.
view full answer... - 4-Pole Flat Wiring Harness for 2020 Mazda CX-5I would be happy to help you select a wiring harness for your 2020 Mazda CX-5. The Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector item # C56377 you were looking at does fit your vehicle but I recommend going with the Tekonsha. The Tekonsha T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector item # 118746 connects in line behind your CX-5's rear tail lights and plugs directly into the lighting harness. This will provide you a 4-pole flat connector...
view full answer... - What is the Difference Between the Tekonsha # 118746 and Curt # C56377 Wiring Harnesses?As far as comparing the Tekonsha T-One Wiring Harness # 118746 to the Curt T-Connector Wiring Harness # C56377, there are more similarities than differences. As far as similarities, both harnesses will provide you with 4-way access on your vehicle to power your trailer's signal lights. Also, both are compatible with 5, 6, and 7-pole wiring adapters and include a hot lead wire that attached to your battery. For the differences between the two harnesses, the Tekonsha harness runs at a higher...
view full answer... - Trailer Wiring Recommendation for 2017 Mazda CX-5For your 2017 Mazda CX-5 the correct Curt trailer wiring harness is the part # C56377. The other kits you mentioned are not a fit for your vehicle so they would not work. Not all vehicles can handle the additional amperage draw of the trailer taillights on the vehicle taillight circuits. Those vehicles need setup that draws power from the battery. Some vehicles have higher rated circuits that can handle this, and others need to have the power drawn straight from the battery to protect...
view full answer...
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Edited by:
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