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ZCI Circuit Protected Vehicle Wiring Harness w/ 4-Pole Flat Trailer Connector and Installation Kit

ZCI Circuit Protected Vehicle Wiring Harness w/ 4-Pole Flat Trailer Connector and Installation Kit

Item # 119250KIT
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Tekonsha Trailer Wiring - 119250KIT
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Install a 4-way trailer connector on your vehicle without cutting or splicing into your wiring. Zero-contact interface sensors identify the current flowing through each wire by simply clamping onto it. Circuit-protected module is made using SMT. Lowest Prices for the best trailer wiring from Tekonsha. ZCI Circuit Protected Vehicle Wiring Harness w/ 4-Pole Flat Trailer Connector and Installation Kit part number 119250KIT can be ordered online at or call 800-298-1624 for expert service.
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Tekonsha Trailer Wiring - 119250KIT

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

Install a 4-way trailer connector on your vehicle without cutting or splicing into your wiring. Zero-contact interface sensors identify the current flowing through each wire by simply clamping onto it. Circuit-protected module is made using SMT.


  • 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)
  • Bypasses factory wiring and involves no cutting, splicing, or plugging into vehicle's wiring
    • Sensors clamp onto the wires of your factory tail light wiring harness to detect current
    • No feedback, no interference with, and no power draw from your vehicle's wiring system
    • Easily removable and transferrable between different vehicles
    • Circuit tester included to ensure proper setup
  • Includes circuit-protected module that connects directly to car battery for power
    • Power wire, fuse holder, and 15-amp fuse included for installation
  • Works with 2-wire, 3-wire, PWM, and multiplex wiring systems
  • 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


  • Application: vehicles with 12V electrical systems
  • Maximum amperage:
    • Stop/turn lights: 4.2 amps per circuit
    • Tail lights: 7.5 amps per circuit
  • 1-Year limited warranty

This revolutionary wiring method makes it fast, easy, and safe to add a 4-way connector to your vehicle so you can power your trailer's lights. Unlike traditional tail light wiring harnesses, which either splice into your vehicle's wiring or plug into designated ports in your factory harness, this system bypasses your vehicle's wiring entirely. Just clamp the intuitive sensors onto the individual wires of your OEM tail light harness and let the ZCI system do the rest.

Zero-Contact Interface Sensors


Each zero-contact interface (ZCI) sensor included with this harness is able to read the current that travels through the wire it is clamped onto. Upon sensing the specific modulation of that wire, a signal can be sent along the wire that connects the sensor to the included 4-way flat trailer connector. That signal is then transmitted through the connector to activate the appropriate function on your trailer lights.

Universal, Worry-Free Design

No Splicing, Cutting, or Connecting to Factory Wiring

Because the ZCI sensors can read the signals sent through your vehicle's wires just by clamping onto them, no cutting or splicing is necessary. The system completely bypasses all of your vehicle's wiring. As a result, your trailer's lights will be powered without overloading your vehicle's electrical system. And there is no chance of damaging feedback either.

When using this ZCI harness, you don't have to worry about voiding your warranty, nor do you need to be concerned about any potentially damaging errors on your part if you're not an experienced do-it-yourselfer. And if you have a vehicle that doesn't allow certain modifications - like a leased car or truck - you can install this harness and remove it later with no obvious alteration to the vehicle.

Maximum Compatibility

This wiring harness is universal. You can use it on any vehicle that operates on a 12V, negative ground system. Because installation is so simple, you can easily remove the unit and transfer it to another car or truck at any time.

In addition, the ZCI sensors are able to read the signals sent by multiplex wiring systems and systems with pulse width modulation (PWM) and low-side-switched wiring, making the harness compatible with nearly all automotive wiring systems. This unit also works with both standard incandescent tail light bulbs and LED bulbs.

Built-In Tail Light Converter

Most trailers run on a 2-wire system - wherein the brake and turn signals are carried on a single wire. Many vehicles, however, are built with separate brake and turn signals. This type of system is referred to as a 3-wire system. If your vehicle operates on a 3-wire system, it will need to be converted so that it will be compatible with the wiring system of your trailer. This is done by adding a tail light converter to your wiring setup to combine the brake and turn signal functions of your automobile so that they run on a single wire to properly activate your trailer's tail lights.

This ZCI unit has a tail light converter built in to ensure proper functioning with any vehicle that operates on a 3-wire system. If your car has a 2-wire system and therefore does not need a converter, don't worry. The method of installing the sensors will take into account the wiring configuration of your vehicle so that only the necessary sensors are used, making sure the appropriate signals are sent back to the 4-way.


This universal harness connects to your vehicle's tail light wiring harness. To connect, just follow the included instructions. There are 4 ZCI sensors included. Each sensor has a colored label on it. Depending on your application, you will need to connect all or some of these sensors to the factory wires indicated in the instructions.

To get the power necessary to operate, the harness must be connected to a 12V power source. The included installation kit provides the hot lead required to connect this module to your car battery. When all connections have been made, connect the hot lead to the black wire on the ZCI power module and run the other end of the lead up to your car battery. Connect the hot lead to the included fuse holder, and then connect the fuse holder to the positive terminal on your battery. Then insert the included 15-amp fuse into the fuse holder.

Once installation is complete, the 4-way connector will be stowed in an out-of-the-way location either within your cargo area or beneath your vehicle, near the trailer hitch. If you choose to mount the connector near your hitch, a mounting bracket (sold separately) is recommended to keep the connector secure.

It is also recommended that you use a small amount of grease on all electrical connections on the 4-pole connector to help prevent corrosion.

Surface Mount Technology

Each ZCI wiring harness is built 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? SMT components 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.

119251 Tekonsha ZCI Zero Contact Interface Universal ModuLite and Installation Wiring Kit

48705 LED Circuit Tester - 12 Volts

Installation Details 119250KIT Installation instructions

California residents: click here

Customer Reviews

ZCI Circuit Protected Vehicle Wiring Harness w/ 4-Pole Flat Trailer Connector and Installation Kit - 119250KIT

Average Customer Rating:  4.7 out of 5 stars   (351 Customer Reviews)

Install a 4-way trailer connector on your vehicle without cutting or splicing into your wiring. Zero-contact interface sensors identify the current flowing through each wire by simply clamping onto it. Circuit-protected module is made using SMT.

- 119250KIT

The product works well for the most part. The only issue is that it doesn't trigger the brake lights on my Kendon motorcycle trailer.

Because you have a motorcycle trailer and not a standard trailer, you will need a converter to separate the circuits of the Tekonsha harness from a 2-way circuit to a 3-way circuit. To do that, use the Curt 2-To-3-Wire Tail Light Converter, part # C56196
Curt 2 to 3 Wire Tail Light Converter
-- Etrailer Expert Katrina B - 05/03/2022

- 119250KIT

I love my hitch, but the installation of this harness for my Audi Q5 was a huge disappointment. I think it's absurd that the wiring has to hang out of the hatch. I ended up buying something different from the installer that could store UNDER THE BUMPER where it should be. Since the box was misplaced, I was unable to return it. I'll maybe try to sell --- or just throw it away. It was an expensive mistake.

- 119250KIT

I used it on a 2017 Chevy bolt (think Chevy discurages people from installing a trailer hitch) since it did not come with any trailer hook up instructions. I think it gave my instaler a work out since he never did one before, but despite the cost I think it was the right way to go instead off cutting into wires etc. I dont use a trailer that much, but it has worked absolutely fine. Only problem has been that I think installer disturbed a wire hook up to a parking light (that is only needed-if lift gate is open) so he has not gotten around fixing that since he has to get into the trunk inards to do it.

- 119250KIT

Super easy to install on my 2013 MINI Cooper Coupe, no cutting or wire splicing needed. The MINI tailights incorporate both LEDs and regular incandescent bulbs and have a somewhat convoluted wiring harness, but I had no issues and everything worked as it should out of the box. Recommended.

- 119250KIT

Installed on a 2018 Audi Q5. Installation was not easy, partially due to working with the panels on the Audi, partially due to the module being hard to configure properly. After 20+ hours working on it, I got it to a point where it correctly recognizes 'most' signals. For whatever reason, the left turn signal does not work, regardless of how many times I adjust the connections and reset the module. It was a cheap solution that gets me 80% of the way there. I'll also note that there is little/no online reference material available, beyond the installation videos that etrailer posted; this makes troubleshooting nearly impossible.

I recommend viewing the video install that we have on a 2018 Audi Q5. Be sure to follow the steps for a 2 wire system in the manual. When one of the functions is not working you would need to start vehicle and turn all functions off: Tail and head lights, brake and turn. Initiate ZCI learn mode by placing 15 amp fuse into fuse holder. Then you would active each function for 5 seconds. The hatch does need to be closed when testing the harness.
-- Etrailer Expert Jenny N - 01/04/2022

- 119250KIT

Great wiring harness, does NOT require and cutting what so ever. Sal FROM customer service is very helpful. I would recommend for a friend to help to make the install go faster. Over all great, dealer said I would need a special computer program for the Harness to work properly, that is incorrect. Just follow the instructions that are included and you will not regret your investment. Car 2018 Audi Q5

- 119250KIT

The trailer hitch and wiring assembly have worked flawlessly. After calling several local installation outfits and receiving estimates of $2,000+ I decided to install myself. I have a little mechanical experience but this was the first hitch and wiring harness for me. This is my wife's X5 so I was a little nervous about popping rivets and pulling the rear bumper cover off, but eTrailer has excellent step by step video instructions by model year. The order included replacement rivets and detailed instructions. They could not have made this any easier. I really took my time and completed the job in about 5 hours. The final install looks professional and clean. The no-splice wiring harness is amazing - worth every penny. Tools: I was able to easily pop off the existing plastics rivets, and installed the new rivets (included from eTrailer) with pliers pretty easily - you may want to borrow a plastic rivet gun from your local hardware or auto parts store. On the X5 your have to cut a small notch out of the underside of the bumper cover. I happen to have a Dremmel which worked well. You may be able to use a razor blade. The plastic is not that thick. Pictures are attached. Thanks etrailer!

- 119250KIT

2012 VW GTI (autobahn edition) Installation (DSG) I had some small issues and hiccups along the way, so in order help out since I couldn't seem to find vehicle specific help, here is what I did. I did buy the CURT 4-way flat connector tester (Item #126) first to make my life easier when testing. It helps. Buy it. First - start by removing the cargo floor carpet and pulling down the drivers side wall carpet. I did find it necessary to take the moulding trim off the top portion of where the hatch cover locks in, along with the rear seat belt guide trim so I could run the wires to the battery cleanly. There is a few star bolts holding the trim alongside the rear seats when folded down, so just do a search if can’t find it (one cover has to be popped off) Second - Wiring. This was a little bit of a guess, as I have 3 wires, and my meter didn’t seem to be helpful since they were so small and close together. Here’s what works (drivers side): - “Stop” module clips over the black/red wire - Middle brown wire isn’t used - “Left” turn signal module clips over the green/black wire - Passenger side right turn signal clips over the green/black wire - I screwed the ground right into a side structure panel Running the battery cable was the bigger time suck. - Stated above I had the drivers side rear panel trim and carpet removed, and I continued removing the front/rear drivers floor sill trim. I ran the black wire along the current loom and tucked it under the floor carpet. - I then ran it behind the hood latch and towards the top of the metal foot rest, keeping it behind the carpet - This is where you get to the firewall. There is a piece of foam. Remove it. Now you’ll see a rubber grommet where the clutch pedal would go through if you have a standard. I took that out, drilled a small hole to run the wire through that I attached the wire to a metal hanger to fish up and to the right of the battery box. Fish it up, grab it, and pull it through. - Slide the grommet back into place (your wire would have been already through it) and snap it on. - Make your connection to the battery and follow initiation instructions.

- 119250KIT

Works, could not get lights to work 100% correct but close enough to use the trailer. Brake lights are on when running lights, and 4way hazard lights don’t work. But turn signals work and brakes dim the trailer lights so good enough. Audi A3 etron

- 119250KIT

This kit works perfectly! A reasonably straightforward installation, though not for a DYI'er who is uncomfortable ripping into the trim and lighting wiring harness of their vehicle. A reasonably accurate wiring diagram is very helpful, but not necessary because trial and error works well with Hall sensors used in this kit (i.e. no cutting and splicing wire is required). Once installed, the trailer lighting load is easily handled by the power module without feedback to the vehicle lighting control circuit, although my setup does not interface with a trailer brake controller so I cannot judge full performance. One hint - do not loose the heavy stock reference card that reminds one of the programming routine, While performing other electrical work on my car needing battery disconnection, I can never remember the programming sequence for the trailer lighting controller. Not to worry, though, the product support site has the info.

- 119250KIT

The Tekonsha wiring harness was a bit difficult to install, as the clip-on connections are a somewhat bulky to fit in my Tesla Model 3's tight spaces. The good news is: they work as promised like a charm with our tiny camp trailer's lights. In truth, I have only had to use them once, but cannot imagine that any unforeseen problems would occur with them in the future.

- 119250KIT

Installed on 2018 Jeep Grand Cherokee Limited with no tow package. Install was kind of a P.I.T.A. But worth doing on your own to avoid the stealership. Not too much electrical knowhow required, as the black wire on Jeep tail lights are all ground. Running the power cable was the most difficult part, and required removing the interior rear quarter panel, which I managed to break a plastic clip. Would not recommend this on a Jeep, as there is no simple way to install this on the interior of the vehicle since the tail lights are wired 100% outside of the car. I’d say skip if you are looking into this for a Jeep, and wait for an OEM trailer harness to come out from mopar.

- 119250KIT

I installed the kit on a 2016 Audi A6. I could not find any videos for this car but did watch the video on the Audi A4 which was helpful. Audis are not easy to get information on and are sometimes difficult to work on. The A4 info was very helpful in accessing the wiring but from there it was trial and error in which wire to use for each function. The sensor is very easy to install although on the A6 it is very cramped to work on. IT TOOK ME CONSIDERABLE LONGER TO DO THE INSTALLITION THAN ESTIMATED. This was not due to the kit but to wire identification and some problems with the wiring on my trailer I hAVE NO PROBLEM WITH THE QUALITY AND OPERATION OF THE KIT. For accomplishing the job I rate it 5 stars. I first saw this kit a couple months ago and though it quite expensive (at that time $xxx +) At the time I ordered it the price was just over $xxx. The Audi is a very high tech car so I decided to pay this to avoid the possible trouble a direct wiring job could incur. The product was shipped promptly but before I received it the price had dropped to $xxx. This does not make me feel good about the value of my purchase. I like your web site and the easy of using it. Sorry I have no photos.

I am not seeing the different price of the product. If you have a screenshot of this, I would be happy to review. Our prices vary depending on manufacturer. We do have a Lowest Price Pledge stating if you find the exact same product on another website for less, will refund the difference plus 10 percent. Please call customer service for help 800-298-1624 with this.
-- Etrailer Expert Sierra K - 10/05/2021

- 119250KIT

Wiring to the battery on my model 3 would have been a pain so I just put a small battery in the back with the module. It is really nice being able to haul a small trailer.

- 119250KIT

Installed on my 2017 Corvette Z06. Easy install and works great. Suggested by one of there tech’s to not void the warranty. No wires get cut or pierced. Thanks for a great product.

The harness, as I said , installed easily and worked perfectly. It’s still working perfectly. As you can see this was not your normal install. The tech did not judge but instead was anxious to help.
David1 H - 04/24/2021

- 119250KIT

I had the harness installed. It is easy enough to do yourself providing you have the tools and mechanical experience. The harness works great and can be removed should I want to use it on another vehicle.

- 119250KIT

Combine this kit with a couple of YouTube videos (Thank you U-haul), the installation isn't difficult. Do purchase a circuit tester with an attachment that wraps around a wire and pierces the insulation. The cheap circuit tester that comes with the kit is worthless.

This product has worked flawlessly since installation.
David W - 10/27/2021

- 119250KIT

Excellent product. Trailer wiring works flawlessly with no “wire touch” to the Porsche OEM wiring.

- 119250KIT

The wiring system works remarkably well. I was skeptical of a system that only parallels the original wiring harness instead of a hard connection but it works great and saved me from having to cut in to my cars wiring. I highly recommend this system. The installation video is a bit lacking in a few details but most handy people should be able to figure out the routing through the car body without great difficulty.

- 119250KIT

We own an Audi Q5 and we had the unit professionally install at our local garage. I am disappointed in the way the unit performed. We used it to pull a small uhaul trailer, and the lights worked only spardically. The tail lights worked most of the time, but the signal lights seemed to only work at random. For this emergency trip it was adequate, but I would not reccomend this product.

Thank you for leaving a review! If you are able to, checking the wiring connections and the ground wire may all be all you need to fix the issue. You will want to make sure the ground wire has a direct and clean connection and that other connections are secure. If you reference the install video on this page it may be useful as a visual aid as to where on your vehicle to check for the connections.
-- Etrailer Expert Brooke M - 08/25/2021

- 119250KIT

I am very satisfied with the ZCI wiring harness. However I do not appreciate the amount of emails you are sending me. Remove my email from your promotional advertising. Thank you.

- 119250KIT

This is an excellent kit - bought it for my '17 Chevy Bolt, and installation went without any problems. Just make sure you do things accurately and to best quality. The kit's only as good as your installation.

- 119250KIT

I installed this on a 2019 VW Alltrack. Well designed, works great! Instead of running a power wire to the module per the instructions, I just power it from the 12v connection in the rear of the car as needed.

- 119250KIT

Works better than expected. No "learning required by device. Works fine when powered up, even though i normally remove power between trailer uses to eliminate load.

Trailer hitch and electronics have worked perfectly since installation. Tesla has so much torque, we hardly know trailer is there.
Better t - 10/07/2021

- 119250KIT

My son installed the hitch and the wiring. Hitch was installed and wiring took about 3 hrs. He’s a auto technician and he was amazed seeing a wiring without slicing. Great product.

Show More Reviews

Ask the Experts about this Tekonsha Trailer Wiring

  • Wiring Harness Recommendation For 2020 Audi Q5
    You are correct when you say there are not any plug and play wiring available for the 2020 Audi Q5 at this time. I recommend to use the ZCI Circuit Protected Vehicle Wiring Harness w/ 4-Pole Flat Trailer Connector and Installation Kit part # 119250KIT on the Audi. The ZCI uses clamps to clamp to the vehicle wiring instead of splicing into it since there is not a plug and play option available for you this it he next best option. I have attached an installation video on an Audi Q5 for your...
    view full answer...
  • Power Wire Connection for ZCI Circuit Protected Vehicle Wiring Harness
    No you will want to have that 12V wire connected directly to your battery using the provided fuse holder. It can be tempting to use a fuse panel from time to time but for the safety of your vehicles wiring system and to ensure that your ZCI Circuit Protected Vehicle Wiring Harness part # 119250KIT will work properly you need to get to that battery.
    view full answer...
  • Recommended 4 Way Flat Wiring Harness for 2014 Lexus LS460
    While there is not a "custom" wiring harness kit for you 2014 Lexus LS460, the Tekonsha ZCI Circuit Protected Wiring Kit # 119250KIT is actually a much better solution. Because the sensors of the Tekonsha ZCI kit clamp onto the wiring of your vehicle, there's no splicing and no plugging into your tail lights, so the installation is a breeze. On top of the ease of installation, because it's non-invasive you can easily remove it and use it on your next vehicle if you need a trailer wiring...
    view full answer...
  • Troubleshooting Brake Light Working with Hatch Open for ZCI Wiring on 2012 Audi Q5
    Since the brake lights are only sending power to the pin on the ZCI # 119250KIT when you have the hatch opened on your 2012 Audi Q5 that leads me to believe that you have some wiring that is pinched somewhere. The ZCI should be getting constant power from your vehicle battery and then should activate those different lighting functions once they have established what wire is for what function (instructions say approx 5 seconds so a little longer is okay). I would recheck all of your connections...
    view full answer...
  • Will the Tekonsha ZCI Kit Work on a 2018 BMW X5 40e with M Sport Package
    Yes, the Tekonsha ZCI # 119250KIT will work on your 2018 BMW X5 40e M Sport and is definitely the preferred choice when it comes to luxury European vehicles like yours since it doesn't require splicing into the wiring/electrical system. The harness clamps onto the existing wiring to receive its' signals and will provide you with a 4 way trailer harness for towing. I've linked an installation video of this harness on a similar X5 that can guide you through the installation process.
    view full answer...
  • Wire Colors of Sensor on 119250KIT
    I can certainly try and help you determine the correct clamps for your wires with the ZCI Circuit Protected Vehicle Wiring Harness # 119250KIT. With this kit, the clamps with the red/white wires are the Left Turn and Tail, and the clamp with the longer wire of the two will be the Left Turn. For the clamps with the black wires, which Stop and Right Turn, the clamp with the longer wire between these two will be the Right Turn.
    view full answer...
  • Alternative Instructions for 2016 BMW 2016 X5 Hybrid
    The Tekonsha ZCI Wiring Harness # 119250KIT is so popular because it is a universal kit that will fit and work with most any vehicle, and do so without any wire cutting or splicing. The videos only offer suggested routing for your wires. Your battery pack under the rear cargo deck may mean that you will need to choose a different location for your wires. The only instructions are those that came with your kit. As in the 2015 installation video, I would start with the rear access panel...
    view full answer...
  • Can ZCI Trailer Wiring Kit Fit 2005 Infiniti FX35
    Yes the ZCI Trailer Wiring Kit part # 119250KIT is a fit for your 2005 Infiniti FX35 as it basically fits all vehicles.
    view full answer...
  • Installing Tekonsha ZCI Wiring on a 2019 Volkswagen SportWagen
    While I don't know the color code for the wiring on your 2019 Volkswagen Golf SportWagen, the ZCI Circuit Protected Vehicle Wiring Harness # 119250KIT should have come with a circuit tester so you can use the probe to see what wire carries which function on your SportWagen. I know the instructions for the ZCI wiring can be a bit overwhelming but that's really just because this is truly a universal wiring kit so Tekonsha wanted to get as much info out there as possible. If you check out...
    view full answer...
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  • Can Power Wire for ZCI Wiring Kit be Connected to Cigarette Lighter-Style Plug in Rear of Vehicle
    Although it *could* work, I have contacted Tekonsha about this very situation in the past and their response is to only run the black power wire on your ZCI # 119250KIT to the battery. Reason being that the black power wire is there so that your trailer wiring is drawing power directly from the battery so that it doesn't affect the OEM wiring on your tow vehicle. A lot of 12V cigarette lighter-type outlets are meant for smaller accessories so if enough power is being pulled through it...
    view full answer...
  • Will Tekonsha ZCI Wiring Harness on 2015 Mercedes GL550 Affect Blind Spot and Back Up Sensors
    The Tekonsha ZCI # 119250KIT is a passive device, that only reads the signal going through the vehicle's taillight wiring harness. It won't actually affect or interfere with those signals. I've linked to an installation video showing the wiring harness being installed on a similar vehicle. The wire colors on your GL550 might be different than those shown in the video, but you'll get a good idea of how to identify which circuit serves which lighting function.
    view full answer...
  • Installation of Zero Contact Interface Sensor Trailer Wiring Harness on 2015 Mercedes-Benz GL-Class
    For the ZCI Circuit Protected Vehicle Wiring Harness w/ 4-Pole Flat Trailer Connector and Installation Kit # 119250KIT should not be installed tapping into another power supply like a cigarette lighter. The power draw needs to be directly from the battery to ensure you don't have a power issue from a fuse or other component that isn't designed for that use. Having power to your trailer wiring even when stored is not an issue and you don't want to keep turning power on and off to a controller...
    view full answer...
  • Trailer Wiring Kit Recommendation for 2013 Mercedes GLK350
    The best trailer wiring harness for your 2013 Mercedes GLK350 is the ZCI kit part # 119250KIT which does not require any splicing to install and is a very reliable and well-made kit. This kit comes with everything you'd need to install in your vehicle.
    view full answer...
  • Why Choose a Powered Taillight Converter Over a Non-Powered Model
    There's a couple of factors that determine that. On older vehicles, very few vehicles needed a powered converter, because the vehicle's electrical system used a large enough wire gauge so that there was excess capacity in the vehicle's taillight circuits that could power both the vehicle taillights but also those of the trailer. However, once the vehicle manufacturers started going with smaller gauge wiring to save the cost of the copper plus the weight, many vehicles no longer had sufficient...
    view full answer...
  • Trailer Wiring Harness Fit for 2017 Land Rover Evoque
    I double-checked with the manufacturer, Tekonsha, and the wiring harness you mentioned will not fit a 2017 Land Rover Evoque. The only option for a trailer wiring harness for your 2017 Evoque is the ZCI Circuit Protected Vehicle Wiring Harness # 119250KIT. This harness does not require any splicing or cutting into your Land Rover's wiring, it uses a clamping system for a clean install. I have added a link to the instructions and a video review for you to check out as well.
    view full answer...
  • Trailer Wiring Harness for 2009 BMW X5
    The 119251 is not available separately; it is simply the harness part of the ZCI Circuit Protected Vehicle Wiring Harness w/ 4-Pole Flat Trailer Connector and Installation Kit # 119250KIT. The other part of this kit is the circuit tester which makes the install an easier process. The ZCI kit is the best option for your '09 X5 because it does not require any type of splicing to install in your vehicle (ZCI: Zero Contact Interface); the sensors clamp onto your wiring. I have added a link...
    view full answer...
  • Installing the ZCI Circuit Protected Vehicle Wiring Harness on a 2018 Ford EcoSport
    It's a little odd that the wiring for the ZCI Circuit Protected Vehicle Wiring Harness # 119250KIT isn't long enough for your 2018 Ford EcoSport. I think the issue that you are running into is that you are probably trying to mount the converter in the middle of your vehicle when it would be more beneficial to install the converter on either side of your EcoSport as the Yellow and Green wires for the turn functions have 95" - 97" leads so they can easily reach to the other side of your vehicle....
    view full answer...
  • Can I Use ZCI Circuit Protected Vehicle Wiring Harness On 2018 Porsche Macan
    We have not yet had a chance to install the ZCI Circuit Protected Vehicle Wiring Harness w/ 4-Pole Flat Trailer Connector and Installation Kit part # 119250KIT on 2018 Porsche Macan but it is a confirmed fit. We have not had any bad reviews regarding the kit installed in a Porsche Macan. The installation is pretty simple because the sensors clamp onto the factory wiring instead of splicing.
    view full answer...
  • Installing Tekonsha ZCI Wiring Harness on 2019 Audi A5
    The best way to locate the correct wires behind the tail lights of your 2019 Audi A5 to use for the Tekonsha ZCI Wiring Harness # 119250KIT is to simply test them for function using the included circuit tester. With that being said I was able to track down some wire functions on your Audi A5 that should hopefully at least guide this process. It looks like the wire that carries the left turn signal behind the tail light is gray in color. The wire for the left side running lights is green...
    view full answer...
  • Connecting Wires of ZCI Trailer Wiring Kit to 2013 Audi A6
    Your 2013 Audi A6 has trailer wiring circuits that are combined what use pulse width modulation on the same wire. So according to Tekonsha when you install the # 119250KIT you need to attach the yellow wire of the kit to the brake/tail/left turn wire on the vehicle and the green to the brake/tail/right turn wire. The brown and red wires of the kit are not used.
    view full answer...
  • Does Wire Have to Run to Vehicle Battery When Installing ZCI Trailer Wiring Kit
    I can not recommend you do that since that battery is going to drain pretty quickly and leave you without trailer lighting and you'll have no way of knowing while driving. I know it seems like a hassle but running the power wire up to the vehicle battery is the only safe way we can recommend you install the part # 119250KIT in your 2017 Audi A3. I attached a help article that has tips on this process for you to check out as well.
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  • Wiring Tekonsha ZCI Trailer Wiring Kit to 2008 Inifiti FX45
    For two wire systems like your 2008 Inifiniti FX45 Tekonsha says to wire up the ZCI kit part # 119250KIT to the vehicle wiring by using the yellow wire ran to the left turn/brake signal wire, the green to the right turn/brake wire, and the brown to either of the tail light/headlight circuits. You didn't mention exactly how you wired your vehicle to the system but I'd verify that you wired it all up like that.
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  • Recommended Trailer Wiring for 2019 VW SportWagen
    The best trailer wiring harness available for your 2019 VW Golf SportWagen is the Tekonsha ZCI Circuit Protected Harness # 119250KIT, as it uses unique zero-contact sensors to identify the current flowing through each wire by simply clamping on to it. In actual practice this just means that you don't have to actually cut/splice into the factory wires on your brand new vehicle. This, along with the powered converter that will power the trailer lights (instead of using power from the actual...
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  • Does Trailer Wiring for 2017 Mercedes GLE 350 use 2 or 3 Wire Wiring
    Your 2017 Mercedes Benz GLE has separate turn signals from the brake lights so you'd use the 3 wire setup when installing the wiring kit part # 119250KIT.
    view full answer...

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