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Curt Circuit Protected Converter w/ SMT

Curt Circuit Protected Converter w/ SMT

Item # C56175
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Wiring

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C56175 - 4 Flat Curt Trailer Connectors
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Install a 4-way trailer connector on your vehicle with this wiring harness with tail light converter. Harness splices into existing wiring. SMT construction ensures superior performance. Lowest Prices for the best wiring from Curt. Curt Circuit Protected Converter w/ SMT part number C56175 can be ordered online at etrailer.com or call 800-298-8924 for expert service.
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Curt Wiring - C56175

  • Trailer Connectors
  • Vehicle End Connector
  • 4 Flat
  • Plug and Lead
  • Curt

Install a 4-way trailer connector on your vehicle with this wiring harness with tail light converter. Harness splices into existing wiring. SMT construction ensures superior performance.


Features:

  • Provides a 4-pole flat trailer connector for the vehicle
    • Compatible with 5-pole, 6-pole and 7-pole adapters (sold separately)
  • Hardwires to existing harness behind tail lights
  • Solid one piece construction
  • 16 Gauge bonded wire with 4-flat plug
  • Factory appearance
  • Simple do-it-yourself instructions on every package
  • Not recommended for vehicles with LED lights


Specs:

  • Wire configuration:
    • Red: brake lights
    • Yellow: left turn lights
    • Green: right turn lights
    • Brown: Tail lights
    • White: ground
  • Wire gauge: 18
  • 1-Year limited warranty


Tech Tip: It is always a good idea to apply a small amount of grease to all electrical connections to help prevent corrosion.


Warning: Overloading circuit can cause fires. Do not exceed lower of towing manufacturer rating or:

  • Max. stop/turn light: (3 amps)
  • Max. tail lights: (7.5 amps)

Read vehicle owner's manual and instruction sheet for additional information.


Surface Mount Technology (SMT) is a method for constructing electrical circuits where components are mounted onto the surface of printed circuit boards.



56175 CURT Vehicle Wiring Harness - 4 Wire

Installation Details C56175 Installation instructions

This Product Fits The Following Vehicles



California residents: click here



Customer Reviews

Curt Circuit Protected Converter w/ SMT - C56175

Average Customer Rating:  4.7 out of 5 stars   (254 Customer Reviews)

Install a 4-way trailer connector on your vehicle with this wiring harness with tail light converter. Harness splices into existing wiring. SMT construction ensures superior performance.

- C56175
by:
1997 Honda Civic

I have been ordering from etrailer.com for over 10 years. They have always provided exceptional service and great products. 374744



- C56175
by:
2003 Saturn LW300

The trailer wiring adapter worked fine on my 2003 Saturn LW300. The unit construction was excellent. I did have to spend a while finding the proper wires in areas that were practical to splice in and had to do a lot of "pinning" with a voltmeter to determine which wire carries the correct signal. This may be difficult for someone with little experience in wiring. Most connections were made in the spare tire compartment with one behind the right tail light, all within the vehicle. Overall I am very satisfied with the product. 117895



- C56175
by:
2010 Jeep Liberty

These items are just as they are said to be. Installation was fast and easy. I would highly recommend Trailer and these products. I will buy from them as the need arises. 109323


Comments
Still very happy with this product. Hasnt given me any problems. Going to be purchasing another for my other jeep.
Ken - 12/06/2014

7899

- C56175
by:
1996 Jeep Cherokee

Something is defective with this unit. While the running light circuit is fine, the circuits that convert the brake and turn signals into a single circuit (the essence of the device) is intermittent; sometimes it works properly, sometime only the left light responds, sometime only the right, sometimes nothing. I believe the problem is due to a bad diode in the unit. I am experienced with these devices, so it is not an installation error. Due to the installation, I am unable to return the unit in unused condition. 1996 Jeep Cherokee. FYI- this unit was purchased to replace a similar unit that started having a different problem after ten years of use. 573190


Comments
When a wiring harness is acting up, the first thing youll want to do is isolate the cause to the vehicle or the trailer wiring. Use a standard incandescent circuit tester like our part 40376 on each pin of the trailer connector as each function is activated. If youre not getting signal on the trailer connector pins, try testing on the input side of the converter. If the signal is entering but exiting the converter box, youll have confirmed that the converter is bad. Youll also want to ensure that the ground connection is secure. An insufficient ground can cause all kinds of odd behavior in the lighting. Ill link you to an help article on trailer wiring troubleshooting.
-- Mike L - 10/10/2018

44491

- C56175
by:
2005 Hyundai Elantra

OK this product is great, installs quickly with the supplied tap connectors and works as expected. i installed on a 05 Hyundai Elantra. Do yourself a favor and save yourself hours of troubleshooting. take some sandpaper and scratch off the paint on the metal surface of the car. I did it inside the light access panel. Use the supplied self tapping screw to make a Solid ground or your trailer lights will not work! i took a shortcut and secured to a screw in the panel, with paint under it. While this was sufficient ground for my test light, it was not for the trailer lights. <- this really threw me off and i wasted a lot of time troubleshooting. i even thought my trailer lights were bad and got a replacement set! but no good until i grounded properly. PS tech support was AWESOME! i had to call twice, once for the hitch install, another for trailer light issue. they answered my questions quickly and even helped me troubleshooting my trailer light issue!. When it comes time to get a hitch for my wife's van, i am definitely re-ordering from etrailer.com. 90890



- C56175
by:

895665



- C56175
by:

895372



- C56175
by:

Fast, knowledgeable and professional, a special thanks to Courtney for her excellent customer service! 894537



- C56175
by: 09/24/2020

Still works with no problems at all. 891931



- C56175
by:

You will never have buyers remorse if you buy from these folks, I guarndamtee it! 889560



- C56175
by:
2004 Volkswagen Jetta Wagon

Great service and the installation was a breeze!! 881669



- C56175
by:
1991 Jeep Cherokee

861048



- C56175
by:

Another great product, delivered by the best retailer in the web, etrailer.com!!!! 856910



- C56175
by:
1999 Toyota 4Runner

The previous trailer light relay on my 1999 4Runner gave out after a few years. Hoping that the improved circuitry in this Curt model holds up better. It's been over a year now. Good so far. 845906



- C56175
by:
2006 Volkswagen Golf

I'm no mechanic and I loathe messing with electrical but I was able to watch the Curt product video on youtube and in about an hour had the thing installed and my trailer lights working. Simple and effective. Pulled my motorcycle to the track yesterday and all my lights worked! (And I was really surprised how fast this arrived. I didn't pay extra for any expedited shipping but it was on my doorstep in two days.) 837266



- C56175
by:

I called and talked to Steve Z. he was a very pleasant man to talk to. I had my order all wrong and he got all straitened out. He shipped it out the same day, and I received in very quick time. He is a very good representative for your company! 844914



- C56175
by:
Nissan Cube

Correct hitch and wiring harness for my slightly uncommon car (Nissan Cube) was easy to find on the etrailer website. Local shop installed the hitch and wiring for $205. Haven't used it yet but seems to be fine. 815890



- C56175
by:
2003 Volkswagen Eurovan

Great price for the product I was looking for. Good recommendations for compatible accessories. 807861



- C56175
by:
2000 Volkswagen Jetta

Easy to install, everything works as it should and good quality. 799617



- C56175
by:
2004 Oldsmobile Alero

This worked great for me on my 2004 Oldsmobile Alero. If your familiar with wiring this will be a quick install for you. Every car is different so it may take you a bit to find the wires. The longest part of installing these for me is just figuring out which wire is which. I usually unhook a taillight at the connector and use a grounded testing light and then make my connections. The kit includes snap lock wire connectors, but you can solder if your application calls for stronger connections. 799451



- C56175
by:
2007 Hyundai Accent

Procuct worked wonderful and quality was very good. Most of the time I spent on install was removing panels and replacing them. Acutal connections was a piece of cake. I highly recommend this product. Bill 799310



- C56175
by:

product took a couple days to ship. otherwise, no complaints 792982



- C56175
by:

The quick splice were a bit oversized for my Audi wiring. Required me to wiggle it a bit to get a good connection to the, my guess 22ga, wire. Could also use at least a few more zipties. Otherwise, this is a good kit. 792429



- C56175
by:

Works great. I prefer to cut and solder the connections as opposed to the vampire clips. Just a personal preference though. 785680



- C56175
by:

Worked flawlessly on my 1992 Jeep Chero kee 785102


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Show More Reviews

Ask the Experts about this Curt Wiring

  • Trailer Wiring Recommendation for a 2009 Kia Sportage
    For your 2009 Kia Sportage a wiring kit with circuit protection is recommended. If you were to install a harness without the circuit protection like the Draw-Tite Wiring # 18252 you would most likely blow some fuses as well as potentially damage your tail light circuits. Even with your LED taillights. For an easy to install wiring harness confirmed to fit your vehicle I would recommend the Curt Wiring Harness part # C55529. This plugs into your vehicle's wiring harness, which is located...
    view full answer...
  • Trailer Wiring Harness With a Powered Converter for a 2003 Volkswagen Jetta Wagon
    We do have a wiring harness with a powered converter for your 2003 Volkswagen Jetta Wagon. I recommend using the Tow Ready Upgraded Circuit Protected Modulite, # 119179KIT. Since you are having power issues with your current wiring harness, I recommend removing that wiring harness completely and install the Tow Ready harness per the installation instructions. I have attached the instructions for you to check out. This harness includes a circuit tester, so I recommend using that circuit...
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  • Troubleshooting Trailer Wiring Install that Shows No Blinkers but Other Circuits are Active
    If you test the pins of the 4-way right now do they flash with the blinkers? It's bizzare that the higher drawing circuits of stop and running lights would work but the blinkers would not. Typically that's a converter box issue so let me know if those circuits test positive with a tester. If not test the input side of the box too to see if the correct voltage is making it into the box. If not, then the issue is connections.
    view full answer...
  • Installing Trailer Wiring Harness on 2006 Scion xB
    The Curt # C56175 trailer wiring harness you mentioned is not a vehicle specific item, it can be used with many different vehicles and therefore there are no vehicle specific instructions available. To install the wiring harness, having a circuit tester like part # 40376 would be very helpful. Locate the wiring harness feeding both of the taillight assemblies. You might need to do some disassembly in the cargo area of the vehicle or remove the taillight assemblies as if you were replacing...
    view full answer...
  • Wiring 4-Way And 7-Way Connector On 2004 Jeep Liberty To Tow Popup Camper
    If you are wanting a 7-way connector at the back of your 2004 Jeep Liberty and you have brakes on your pop-up trailer, and you currently have no connector installed, part # C56175, and part # ETBC7, will do just that. I have attached a helpful article that explains how to install the # ETBC7 you can check out. You will also need a brake controller. I recommend the Tekonsha Prodigy P2 Brake Controller, part # 90885. This is our more popular brake controller because it is easy to install...
    view full answer...
  • Parts Needed to tow a Trailer with a 2005 Volkswagen New Beetle
    First thing you want to do is consult the owners manual of your 2005 Volkswagen Beetle to determine if there are any restrictions on towing with your vehicle. For a hitch you would want the part # 24679. I attached a set of installation instructions plus an install video for this hitch to the right. For a ball mount you will need the part # 3593, for a 1-7/8 inch hitch ball # 19256, or depending on your trailer you may need a 2 inch ball. For that you would want part # 19258. You...
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  • If there is a Short Circuit Will Curt Converter Box Blow or Just the Affected Circuit
    Normally when there is a short circuit it will blow the converter box no matter what the brand is. But sometimes it will only affect the one function that shorted like what you have experienced. It could go either way but regardless of what does happen you would need to replace the converter to fix the issue. We do have the plug in style T-connector # 118418 that you can use instead of a hardwire harness if you hare interested. I have linked instructions and a video for you to view. You...
    view full answer...
  • Wiring Diagram for the Curt Trailer Wiring Harness Part # C56175
    I really wish I had a diagram specific to your 2004 Nissan Quest that shows how it would install, but the best I can do is show you a diagram that shows you what circuits the Curt Harness part # C56175 would wire to. You will need to use the included circuit tester to determine the functions of all of the taillight circuits and then wire them accordingly. I also attached a copy of the installation instructions for this harness for you to check out.
    view full answer...
  • Grounding T-Connector for 1995 Jeep Grand Cherokee
    The Curt # 55260 T-One wiring kit does not require a separate ground connection, because the ground connection is made in the plug that connects inline with the vehicle wiring harness feeding the passenger side tail light assembly. You can see this by looking at the photo I have edited for you. In other words, you are not missing anything. You can see the installation instructions by clicking the provided link.
    view full answer...
  • Instructions for the Curt Wiring Harness # C56175
    I attached installation instructions for the Curt Circuit Protected Converter # C56175 that you referenced. I will send them to you in a separate email as well.
    view full answer...
  • Trailer Wiring Harness Options for a 1997 Toyota Camry
    There is a T-connector wiring harness for your 1997 Toyota Camry. You can use wiring harness # 118358. It just plugs in line with the tail light wiring and grounds to a clean metal surface. I have included a link to a video showing installation on a 1998 Camry and the process will be the same on your 1997. I have also linked the instructions for you. To install the Curt harness # C56175, you would still need access to the tail light wiring on the vehicle. But you would need to use a...
    view full answer...
  • 4-Way Trailer Wiring Harness for 2000 Honda Civic EX
    Yes the Curt Circuit Protected Converter # C56175 is compatible with your 2000 Honda Civic EX. It will also work with your boat trailer if it has a 4-way connector.
    view full answer...
  • 4 Way Trailer Wiring for 2003 Nissan Sentra
    You are correct. The correct trailer wiring kit to place a 4 way connector on your 2003 Nissan Sentra is the Curt Circuit Protected Converter # C56175, which will allow your trailer lights to function in conjunction with your vehicle's brake lights, turn signals and tail lights.
    view full answer...
  • How to Wire a 6-Way Trailer Connector to a Chevy Astro Van
    I really need to know the year of your Chevy Astro to determine the best way to install the trailer connector to the van's wiring. The Astro was produced from 1985 to 2005 so that is a big range. I can tell you that the likely functions of the wires are red or black for 12 volt power, white for ground, brown for running lights, yellow for left turn signal/brake lights, and green for right turn signal/brake lights, and red or black (whichever is not 12 volt power) for trailer brakes....
    view full answer...
  • Curt Trailer Wiring Harness for 2004 Volkswagen Golf has No Left Turn Signal at the 4-Way
    The wiring system on the 2004 Volkswagen Golf is a complex system. It should have combined brake, tail, and turn signal functions on one wire. This means the red and brown wires are grounded and the yellow wire attaches to the combined brake, left turn signal, and tail light wire and green connects to the combined brake, right turn signal, and tail light wire. If this is how you have it set up and there is still no left turn signal on the output side of harness # C56175 then that indicates...
    view full answer...
  • Trailer Wiring Options for a 2006 Jeep Liberty without Factory Tow Package
    There are a few different trailer wiring harnesses available for the 2006 Jeep Liberty without the factory tow package. I have included a link to them for you. I recommend either # 118524 or # C55382 because they plug in line with the tail light wiring on the vehicle. These are the harnesses that fit because the vehicle does not have the factory tow package. Models with the factory tow package are pre-wired with a trailer connector already and the wiring for it is under the vehicle.
    view full answer...
  • Will Curt Trailer Wiring Harness C56175 Fit a 2008 Kia Sportage
    You can use Curt trailer wiring harness # C56175 for your 2008 Kia Sportage. This harness gets the power for the trailer lights from the tail light wiring on the vehicle. You will need a circuit tester to test the wiring on the vehicle to connect to the converter. If you need a circuit tester you can use # 40376, On the Curt harness the white wire grounds to a bare metal surface. Red is brake lights, yellow is left turn signal and brown is running lights. On the right side you will just...
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  • Wiring 1996 Geo Tracker for Flat Towing
    The # C56175 would be installed on your Tracker if you wanted to tow a trailer with it, but it will not work for towing the Tracker behind a motorhome. To wire the vehicle for flat towing there are several available systems, as you can see in the article I have linked you to. A magnetic towing light kit like # RM-2120 would be an easy to use, easy to install alternative. If you would prefer a permanently-wired alternative, the article outlines how to determine which choice is best for...
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  • Troubleshooting Trailer Wiring for Fleetwood Pop-Up Trailer and 2003 Mazda B3000 Pickup
    A potential cause for your issue is a weak ground connection. Trace the white ground wire from your 4-pole back to where it attaches to the vehicle frame. This ground must be secured to a clean and rust-free spot on the frame. If necessary sand off the rust/dirt from that grounding point and reattach the white ground wire or relocate it a new spot. If this does not correct the problem then I suggest you next test your existing 4-pole trailer connector on your Mazda to confirm it is...
    view full answer...
  • Trailer Wiring Harness Recommendation for a 1999 Toyota 4Runner
    If I were you I would go with the Curt Custom Fit Vehicle Wiring # C55341. This isnt one of the wiring harnesses you referenced but I believe it would be your best choice because of how easy it would be to install and because it would be exactly what you need to provide you with a functioning 4-way at the rear of your 1999 Toyota 4Runner. The Curt Circuit Protected Converter # C56175 that you referenced is also a viable option but it would require you to cut and splice into the trailer...
    view full answer...
  • Trailer Harness on 1999 Toyota 4Runner Does Not Work
    Since this is the first time you have used the connector on your 4Runner, if it has been awhile since it was installed or if it is factory then there can be some corrosion build up inside the connector preventing it from working. This happened to a friend of mine recently. Scraping out the corrosion will help. Also make sure the main ground is connected to a clean and corrosion free bare metal surface. If that does not help then use a circuit tester such as # PTW2991 to test the vehicle...
    view full answer...
  • Plug-In Trailer Wiring Harness for a 2016 Mazda 3 Sedan without LED Tail Lights
    For a 2016 Mazda 3 Sedan without LED tail lights you can use # HM11141824 which plugs in line with the vehicle tail light wiring so you won't have to splice wires like you would with some of the other options. I cannot recommend using a wiring harness that the manufacturer states not to use so it would be best to replace the harness you have with # HM11141824.
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  • Wiring Harness For 2013 Chevrolet Cruze And LED Lights
    The difference between LED lights and standard incandescent trailer lights is the amperage (current) draw they require. LED lights require far less power to operate, and some converters will not work with LED lights because they present a very different electrical load that is harder for the converter to recognize. The C56175 you referenced will work with your vehicle if it does not have LED lights. We do not recommend using it for vehicles with LED lights because of the low amperage draw....
    view full answer...
  • Instructions for the Curt Circuit Protected Trailer Wiring Harness part # C56175
    Yes, check out the link I attached. It is a link to the installation instructions for the Curt Circuit Protected Converter w/ SMT # C56175.
    view full answer...
  • Plug and Play Trailer Wiring Options for 2005 Jeep Liberty W/O Tow Package
    We do indeed have two plug and play trailer wiring harness options for your 2005 Jeep Liberty. If your trailer has minimal lighting- just a stop/turn/tail light for the passenger and drivers side, the Curt # C55382 would be an excellent choice. This harness has a simple installation, which would plug inline with the connectors on the back of the taillight assemblies. If your trailer has more extensive lighting, say what is mentioned above plus some clearance and/or marker lights on the...
    view full answer...
  • Trailer Wiring Harness Options for a 2004 Infiniti FX35
    I do have an option for you but I spoke with Curt and they said that none of their converter boxes will work with the 2004 Infiniti FX35 therefore no, the Curt Circuit Protected Converter part # C56175 will not work. The only trailer wiring harness we have confirmed to work with he 04 FX35 is the ZCI Circuit Protected Vehicle Wiring Harness part # 119250KIT. This kit uses sensors to clamp onto the wires therefore no splicing is required. The only other option you will have if the ZCI Circuit...
    view full answer...
  • Installing Trailer Wiring Harness on 1999 Chevy Astro
    The 1999 Chevy Astro uses a 2 wire system that combines the brake light and turn signals onto one circuit for each side of the vehicle. A standard 4 pole like part # 18002 can be used instead of the # C56175 converter you mentioned. The converter is designed for use on vehicles that have a 3 wire system with the left turn, right turn and brake lights all being separate circuits. The easy way to tell which system a vehicle uses is to look at its tail light assemblies. If the lenses for the...
    view full answer...
  • Installing Curt # C56175 Trailer Wiring Harness on 2006 Jeep Cherokee
    Because there are some plug-and-play options available like the # 118394, we don't have any footage of the Curt # C56175 being installed on a 2006 Grand Cherokee. To install the C56175, you would need to access the wiring harnesses that feed the drivers and passenger side taillight assemblies. Use a circuit tester like part # 40376 on the wires feeding the taillight as each function is activated, one by one. Start by activating the left turn signal. Probe the wires feeding the left turn...
    view full answer...
  • Taillight Converter for Honda Gold Wing with Separate Brake Lights to Allow Use with 4-Pole Trailer
    The 5-pole wiring harness on your Gold Wing has a separate circuit for the brake light signal while 4-pole trailer wiring combines the brake and turn signals onto one circuit, one for the left turn and stop lights and one for the right. To make the 4-pole trailer's combined lighting system compatible you can install a converter # C56175 on the bike that will take in the separate signals and combine them into the 4-pole format. The red input-side wire will connect to the brake light circuit....
    view full answer...
  • Determining Tail Light Wire Functions to Install Curt Harness # C56175 in 1995 Mitsubishi Montero
    Since the wire colors used by vehicle manufacturers are not always consistent, your best option to identify which wires to connect to your Curt Trailer Wiring Harness # C56175 is to use a circuit tester such as # 40376 to identify each wire by its function. Wire color alone is not a reliable way to identify function. With a helper on hand to activate the vehicle lighting functions for you (one by one) apply the grounded circuit tester to each wire at the driver-side taillight assembly...
    view full answer...




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Info for this part was:

Expert Research:
Mike L
Expert Research:
Sarah L
Expert Research:
Michael H
Expert Research:
Jameson C
Expert Research:
John H
Expert Research:
Adam R
Expert Research:
Jeffrey L
Video by:
Andrew K
Video by:
Joshua S
Video by:
Dustin K
Test Fit:
Nicholas E
Test Fit:
Andrew S
Video Edited:
Jacob T
Video Edited:
Chris R
Updated by:
Adele M
Updated by:
Sarah W
Updated by:
Kristina F
Updated by:
Isabelle B

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