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  1. Custom Fit Vehicle Wiring
  2. Chevrolet
  3. Blazer
  4. 2003
  5. Tekonsha
FITS 2003 Chevrolet Blazer
4-Way Flat Trailer Connector w/ 72" Harness, Circuit Tester and Wire Taps

4-Way Flat Trailer Connector w/ 72" Harness, Circuit Tester and Wire Taps

Item # 18252
Our Price: $29.08
Custom Fit Vehicle Wiring
Confirmed to Fit
2003 Chevrolet Blazer

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Tekonsha custom fit vehicle wiring for your 2003 Chevrolet Blazer are available from etrailer.com. Installation instructions and reviews for your Chevrolet custom fit vehicle wiring. Expert service, and great custom fit vehicle wiring prices. etrailer.com carries a complete line of Tekonsha products. Order your 4-Way Flat Trailer Connector w/ 72" Harness, Circuit Tester and Wire Taps part number 18252 online at etrailer.com or call 1-800-940-8924 for expert service.
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2003 Chevrolet Blazer - 4-Way Flat Trailer Connector w/ 72" Harness, Circuit Tester and Wire Taps

  • Trailer Hitch Wiring
  • 4 Flat
  • No Converter
  • Tekonsha

This universal, splice-in wiring kit includes a 4-way flat connector, circuit tester, 72" of bonded wire, and 4 wire tap connectors. Color-coded, bonded wires have functions printed on them to make installation easier.


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)
  • Works with 2-wire electrical systems
  • Splices into your vehicle's wiring with the included quick-splice connectors
    • Bonded wires are color coded (see wiring configuration below) and labeled
    • Included circuit tester helps ensure wiring is correct during installation
  • Includes durable, molded-rubber, standard female output socket


Specs:

  • Harness length: 72"
  • Max amperage: 7.5 amps per circuit
  • Wire gauge: 18
  • Limited 1-year warranty


4-Way Trailer Connector Installation

Because the color/function of the wires on this connector may not match the color/function of those on your vehicle, be sure to use the included tester to double check the function of each wire on your vehicle's tail light wiring harness before installing this connector. Once you've figured out the functions of your vehicle's wiring, use the included quick-splice connectors to connect the corresponding wires on the trailer connector. Quick-splices, or "wire taps," offer a quick way to make connections without you having to strip and twist wires. Just place the wires in it and snap the cover down.


The number 1 reason trailer wiring comes up faulty is a bad ground, so make sure your ground wire has a solid and clean connection to metal. To make this connection, you'll need a self-tapping screw and a ring terminal (sold separately).


Wiring Configuration

Wire Color Wire Function
Green Right turn and brake light
Brown Tail lights and running lights
White Ground
Yellow Left turn and brake light


Quick Tips:

We install a lot of wiring harness around here, so we thought we'd share a few tips we've picked up over the years:

  • Butt connectors - especially heat-shrink ones - provide the most secure, longest-lasting connection, so we'd recommend you grab a few and swap them out for the quick-splices in this kit.
  • Use a circuit tester on the plug terminals once the harness is installed to make sure everything's working. There's nothing worse than figuring out that you have a bad ground or a faulty connection right before you're about to hit the road.
  • Be sure to put a little bit of dielectric grease on the 4-way plug to protect the terminals from dirt, grime, and corrosion.


18252 Tekonsha Chevrolet Blazer Wiring Harness with Chevrolet Blazer End 4-Pole Connector Kit and Circuit Tester - 6' Long

20252 Alternate

Installation Details 18252 Installation instructions

California residents: click here


Customer Satisfaction Score:


Customer Reviews

4-Way Flat Trailer Connector w/ 72" Harness, Circuit Tester and Wire Taps - 18252

Average Customer Rating:  4.6 out of 5 stars   (209 Customer Reviews)

This universal, splice-in wiring kit includes a 4-way flat connector, circuit tester, 72" of bonded wire, and 4 wire tap connectors. Color-coded, bonded wires have functions printed on them to make installation easier.

by:
2014 Smart fortwo

Thanks to the video I did not have a problem installing the trailer wiring on my 2014 Smart Fortwo.
Thanks

Vincent S.

5/31/2020

Just fine.



by:

Awesome product never any issues use along easy install practically don’t need instructions



by:

Worked great for 6 mo. Ish. I’ve had the right side wire become loose/break so occasionally the right side will randomly choose to quit working but (at least for me) that’s not a huge deal with how little I use my trailer. solid purchase overall.

Etrailer Expert

Katrina B.

11/18/2022

I have contacted the manufacturer and the have suggested that the wiring harness should be checked for a good connection, it sounds like the harness may not be connected correctly.



by:
Chevrolet Corvette

This harness worked great for my Corvet te.



by:

First thing I noticed were the online videos that can be saved to a file. nice! also noticed the instructions for assembly of the tow bar was small and difficult to read, (my mechanic was crying throughout the installation) There were no instructions on the wiring kit installation, even a photo of the wire to wire color placement would have helped, but my mechanic went on line and got the photo from an outside source - thus the 4 stars, not five. - other than that it worked out very well, the products are solid, well made, and superbly engineered. everything was inside! thanks !

Etrailer Expert

Mike L.

3/15/2019

We have a link to the installation instructions as well as some install videos on the product description page.



by:
1990 Dodge Van

Took me almost a year to actually get to installing this on the van, but wanting to use the trailer was a strong motivator. Its just a basic wiring set with quick connect clips in a bag. The fact that I was installing this on an extended camper version of the van this was designed for complicated the install, but "fortunately" there were enough rust holes that I could drill where I need to drill. Wires were long enough for the job (exactly the length needed) and the clips came pre-filled with silicone grease. Nice. Came with no instructions, but the on-line installation video is *excellent* and guided me thru the entire process. Overall, it was a convenient way to buy and install a wiring harness on my older van. Only two minor complaints:
* Did NOT include a weather-proof cap for the plug, which hangs outside by the hitch. I took the one included with the wiring kit for my Suburu (from etrailer) since that plug is stored inside the vehicle.
* The 12v circuit tester did NOT work. Fortunately I had my own tester.



by:
1984 Jeep CJ-7

I got a 4-wire harness to connect my jeep to a utility trailer. The harness worked perfectly.
The connectors were good--surprisingly, they were stuffed with noncorroding gel so that the jeep's wires are protected. There were no specific instructions for the hookup, but simply removing the taillight lenses showed which color wires to splice.
The supplied tester failed to function, but that wasn't a problem at all--I didn't really wish to poke additional holes into the wires anyway.
Took a half hour to complete.



by:
2007 Ford Focus

This was a pain in the rear end. Wires were not labeled and the tester was useless. Had to go to online for some instructions (none included with kit). Took a long time to get it wired to the car.

Etrailer Expert

Mike L.

12/17/2018

On the product page, we have a link to the instructions as well as a couple of install videos.



by:
2006 Ford Focus

The installation documentation, along with the video aid, was very helpful and easy to understand. It helped a lot, and made the installation fast and easy. I like it a lot, and I appreciate the support I got on a minor issue which was easily and quickly taken care of.

Russell

4/4/2018

The products I purchased work beautifully! I haven’t experienced a single issue with anything.You guys are terrific!



by:

Product as described and very easy to install. In my case it didn't work, because the original wiring on my truck apparently is bad and I couldn't figure out what was faulty, so I ended up getting another harness that plugs into existing tail light harness, which worked great.



by:

Each trailer is the best. Very easy to order from. Also, Sherry was very helpful and friendly.



by:
1992 Dodge Van

Over all good experience
Missed the bolt
package in my delivery but it was sent out right away... Friendly customer service... Hitch went on without a hitch. Great product..I will use this company again.. Thank you



by:
1998 ChevroletBlazer

Only thing that needed to be changed was wire connectors. Type included with the plug are easy to install (no insulation stripping, just clamp) but are not reliable. Throw those away and use standard crimp butt splices. Plenty of wire included, so I cut to more convenient length, spliced, and taped 8 inches on both side of splice. Tester is a nice touch, save in your tool box after installation.



by:
2005 Ford Focus

I installed this wiring kit along with a hitch. This was pretty easy to install, and the directions were easy to follow. The hardest part was pulling up the the liner in the hatch back area to get to the wires.



by:

I needed a hitch and wiring harness to pull a small trailer for hauling lumber. The harness was easy to install and has worked without any problems over the past year.



by:

The box of contents I received was partially damaged and the boxes inside not properly secured and wrapped and damaged inside.There was a hole in the box and am missing one elecrical connector. Everything else was O.K.

Etrailer Expert

Jenny N.

11/16/2021

I will have our customer service team reach out to you.



by:
2001 GMC Sierra

Has held up great over a year so far. I recommend wrapping the wiring in electrical conduet to help make the set up last even longer like I have

Kyle

3/23/2018

Perfect!



by:

Your product was easy to install and works fine. However, one thing that I think would be a good idea, would be to include a set of installation instructions with the product. I didn't know that the metal tabs on the connectors had to be pushed all the way down before snapping the plastic hinge over the top of the tab. A friend of mine informed me of that.



by:

I purchased the Draw-Tite Receiver and wiring kit. All parts were easily identified. Good printed instructions. Everything assembled easily and fit perfectly. It took about 1.5 hrs to complete. It will be used to tow a small utility trailer. Highly recommend this equipment and etrailer.com. Thanks.



by:

Their customer service is amazing and within a few day my order was here.



by:

Ordered a few weld on trailer hitch receiver tubes among other trailer parts. Parts were delivered in a timely manner and the quality of the receiver tubes is excellent. I will buy from this group in the future when I need trailer parts.



by:
2006 Chevrolet Malibu

I watched the video online to install the wires and did it all by myself. Product arrived in good condition.

Tj

12/26/2014

No problems, whatsoever! Good product for the price. I especially loved the fact that one could watch the video online on how to install it. Thanks!



by:
2013 Ford Edge

Worked perfect. I used it to extend the pigtail on my tow dolly. etrailer has great shipping & service. Have bought from them many times.



by:

4-pole Hardwire Kit with circuit tester.

I
needed the kit to attach rear (break/lights/back-up/tail lights) assembly.



by:
Hummer H3

Everything was sent according to order and mailed extremely quickly. Product was easy to use on a Hummer H-3 for a trailer hitch.


25
209
Show More Reviews

See what our Experts say about this Tekonsha Custom Fit Vehicle Wiring

  • Brake Controller Show Full Voltage with Manual Override But Half with Brake Pedal
    Many proportional brake controllers require that the vehicle be moving to send back the full voltage when stepping on the brake pedal. Depending on the brake controller you have this could be what is going on. You may also need to adjust the output settings. The manual override will send back the full amount of voltage (up to what it is set at) but it may not do so with the brake pedal depending on the controller and its settings. I have included a couple of links on testing and troubleshooting...
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  • Wiring Diagram and Instructions for 4-Pole Hardwire Kit with Circuit Tester
    I have the wiring diagram, videos and instructions for the 4-Pole Hardwire Kit with Circuit Tester # 18252, attached to this help page. White Wire = Ground Green Wire = Right Turn/Brake Brown Wire = Running Lights Yellow Wire = Left Turn/Brake
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  • Should I Have 12 Volts At Each Braking Assembly on a Trailer
    What type of brake controller do you have? If you have a proportional brake controller then 12 volts will only be sent to the brakes if you apply the manual override with the settings all the way up. If you still only have 8.9 volts then you may have a short on the blue brake output wire in between the brake controller and braking assemblies or the brake controller is bad. In order to make sure there is not a short on the vehicle side you will need to test the 1 o'clock pin on the 7-way...
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  • Is there a Custom Fit Wiring Harness for a 2009 Smart ForTwo
    Currently there is not a direct plug in harness for the Smart Car. The correct wiring harness is the 4-Pole Hardwire Kit, item # 18252, which includes a circuit tester to find the correct circuits on the vehicle to connect the trailer wiring to.
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  • Trailer Lights Go Out When I Apply Brakes on Tow Vehicle 2002 Toyota Tundra
    It sounds like there is a bad ground connection somewhere on the trailer because your lights are working when they are not put under a load. Whenever your tail lights are on and then you apply the brakes, the system is under max amp load, and with a bad ground the lights cannot support all the amps. I would start by checking the ground connections of the tail lights on the trailer to make sure there is a good connection to a clean metal surface. You will also want to inspect the wires to...
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  • Trailer Wiring Harness for a 1983 Dodge D150 Pickup
    For your 1983 Dodge D150 pickup you will need to use a hardwire harness, # 18252, because there aren't any T-connectors that are confirmed to fit. The good news is the hardwire harness costs less and is not all that difficult to install at all. I have linked a video showing the process of testing the vehicle wires and installing the harness.
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  • Finding Connector for Install of Tekonsha Trailer Wiring Harness on 2022 Lexus RX 350 w Tow Package
    If you check out the attached install video you'll see exactly where to find the connector to install the Tekonsha 4-way kit part # 18252 on your 2022 Lexus RX 350. If you cannot find it that would indicate you most likely would not have the tow package.
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  • Trailer Wiring Harness Fit for 1982 Chevrolet S-10 Pickup
    For your 1982 Chevrolet S-10 Pickup, you will need the Tekonsha 4-Pole Hardwire Kit with Circuit Tester, part # 18252. This hardwire kit will provide a 4-way flat trailer connector for your S-10. The T-One Wiring Harness # 118312 mentioned in your question is not longer available and is not compatible with the 1982 Chevrolet S-10. I have included a link to the instruction manual for the Hardwire Kit.
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  • Installing Hardwire Trailer Wiring Harness On 2001 Buick Regal LS
    Unfortunately there is no plug-in kit available for your 2001 Regal, so to install a trailer wiring harness on your vehicle it will have to be hardwired. I recommend the Draw-Tite 4-Pole Hardwire Kit, part # 18252. I have attached a link to an installation video for this harness on a Century that will be similar. You need to access the wires at the back of the tail lights in the trunk of your Regal. You can use the included circuit tester to identify the correct wires to attach the harness to.
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  • Brake Pedal Only Gives 2.9 Volts on Brake Controller on a 2006 Dodge Ram 1500
    To diagnose this issue I would need to know which brake controller you have. If it has a level adjustment knob on the side and that adjustment is not just right it can affect how much voltage goes on when using the brake pedal. Similarly, if the controller is tilted or turned to one side or the other or otherwise mounted outside of the range specified in the instructions it can cause the controller not to function properly. If mounted and leveled correctly then the issue could be the connection...
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  • Recommended 4-Way Trailer Connector Installation On 2013 Ford F-150
    If your F-150 has a 4-way connector it is typically located near the rear license plate. It can be tucked back up behind the bumper and may even be taped or zip tied to other wires or the frame of the truck. If there is no trailer connector, you will need to use the Draw-Tite 4-Pole Hardwire Kit, part # 18252, and locate the correct circuits behind the vehicle taillights for installation. The kit includes a circuit tester and the quick-splice connectors needed. I have attached a link...
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  • Installing Trailer Wiring on a 1959 Chevy Truck
    The 4-Pole Hardwire Kit, # 18252, is a general hardwire harness. You will use the included circuit tester to probe the wires behind the tail lights. On the driver side, you will attach the yellow wire on the harness to the tail light wire that carries the left turn signal and brake lights. The brown wire will attach on the driver side to the tail light wire that carries the running light signal. The white wire is ground and will attach to the vehicle frame. The green wire will get routed...
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  • Reinstalling Heat Shield After Installing Trailer Hitch on 1998 Buick LeSabre
    The Draw-Tite Trailer Hitch Receiver - Custom Fit - Class II - 1-1/4" # 36216 (no longer available) for your 1998 Buick LeSabre requires removing the heat shield which requires removing rivets, and even cutting or bending the heat shield if it is going to be reinstalled. The reinstallation is not required, but if desired would require riveting or reinstalling with screws slightly larger than the rivets to bite into the same location for a solid connection.
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  • 4-Way Replacement Recommendation to Replace a Thick 4-Way on a 2013 Ford Edge
    I think the easiest solution would be for you to cut the 4-way off of your 2013 Ford Edge and then wire up a new 4-way to the wires. You could use the 4-Pole part # 18252 you referenced for this and you would be able to connect to your trailer without a problem.
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  • Troubleshooting Brake Controller that Only Shows a Few Volts When Tested with Brake Pedal
    If you have a proportional brake controller you won't get full voltage when using the brake pedal and testing the pin since the controller needs to see sense deceleration before really applying voltage. If you have a proportional brake controller like it sounds like you do this would be what's going on. A lot of proportional controllers will put out a very small voltage spike when they sense that the pedal is applied which explains why you saw a small amount.
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  • How to Add 4-Way to Wiring of 5th Wheel Trailer
    To wire in a 4-way you'd want the part # 18252 which comes with quick splices that you'd use to tap into the wiring of the first trailer. You have standard 4-way trailer wiring colors correct but your trailer may use different colors so you'd basically just have to check out the wiring that runs to all the lights of your trailer assemblies so that use the correct circuits. The # 18252 comes with a circuit tester to so you can test the wiring too and be sure.
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  • Installing Tekonsha 4-Pole Hardwire Kit on 2004 Chevy Blazer
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  • Troubleshooting Trailer Brake System That is Only Showing 5-Volts at Trailer Connector
    With the brake controller gain turned all the way up, you should be seeing closer to 12-volts at your trailer connector. You are losing voltage somewhere between the brake controller and the trailer connector. I am assuming that by electric brake contact, you are speaking of the brake voltage output pin on the trailer connector. Make sure your controller is properly installed and leveled according to the instructions. Use your tester on the blue brake output wire at the rear of the brake...
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  • 4-Way Trailer Wiring Connector Recommendation for 2001 Ford F-250
    For your 2001 Ford F-250 we have trailer wiring harnesses that are confirmed fits but they are universal, hardwire style. The part # 18252 is what's recommended and it splices into the wiring of your taillights to provide you with a 4-way. In the meantime I attached a help article down below that covers troubleshooting trailer wiring issues for you to check out as well.
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  • How To Install 4-Pole Hardwire Kit 18252
    The 18252 hardwire kit needs to be cut and spliced to your vehicle taillight assembly wires. I have included a link to a video of a hardwire install on a 2000 Dodge Neon. There are plug and play type wiring harness that are easier to install for some vehicles. I would be happy to confirm what the best wiring option is for your vehicle, if you write back with your vehicle year, make and model.
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  • Trailer Wiring Harness that Fits 2003 Chevy Blazer
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  • Trailer Wiring Harness Fit for a 1981 Chevy El Camino
    The # 18252 would work for your 1981 Chevy El Camino, you would need to splice the harness into the existing wiring behind the tail light assemblies. I will link you to an install video that will walk you through the process. The video shows an install on a different vehicle, but the process would be very similar on your El Camino.
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    Image 1 for
  • Solution for Trailer Wiring Harness on a 2008 Ford F-150 With Dead CIRCUIT at Fuse Slots
    If there isn't power to either side of the fuse slots on your truck when the blinker is on that is not a great sign. That would indicate a much larger problem upstream of the fuse box. To save yourself the headache, you might just bypass the factory 4-way by installing a part # 18252 which would just hardwire to your truck's wiring.
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  • Trailer Running Light Pin on 2013 Ford F-150 Trailer Connector has No Power
    It could be a tow package fuse or relay that is causing the trailer running light circuit to fail on your 2013 Ford F-150. In the power distribution box the fuse that feeds the trailer park lamp relay is in position 6. Also check position 67. I am almost certain that it is a fuse/relay that needs to be replaced but if not then like you said this is an issue somewhere in the wiring that will need to be tracked down.
    view full answer...


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