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  1. Tow Bar Wiring
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Heavy Duty Magnetic Tow Lights - 20' Wiring Harness with 4-Way Flat Trailer Connector

Heavy Duty Magnetic Tow Lights - 20' Wiring Harness with 4-Way Flat Trailer Connector

Item # TL21RK
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Tow Bar Wiring

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Heavy Duty Magnetic Tow Lights - 20' Wiring Harness with 4-Way Flat Trailer Connector Magnetic Mount TL21RK
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Get lights for towing your vehicle without splicing into its wiring. Magnetic light kit provides a pair of stop, turn, and tail lights. Mounts using large, heavy-duty magnets for increased stability. Plugs in at rear of your motor home. Great Prices for the best tow bar wiring from Optronics. Heavy Duty Magnetic Tow Lights - 20' Wiring Harness with 4-Way Flat Trailer Connector part number TL21RK can be ordered online at etrailer.com or call 1-636-306-4830 for expert service.
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Optronics Tow Bar Wiring - TL21RK

  • Removable Tail Light Kit
  • Bypasses Vehicle Wiring
  • Universal
  • Magnetic Mount
  • Optronics
  • 20 Foot Long Harness

Get lights for towing your vehicle without splicing into its wiring. Magnetic light kit provides a pair of stop, turn, and tail lights. Mounts using large, heavy-duty magnets for increased stability. Plugs in at rear of your motor home.


Features:

  • Light kit allows you to bypass your vehicle's wiring to provide temporary lights for your towed car
    • Can also be used as trailer lights
  • 2 Red lights act as brake, tail, and turn signal lights
  • Magnetic bases let you easily mount lights on trunk or roof of your car
    • Large, heavy-duty magnets provide excellent stability
  • Wishbone-style wiring harness can be easily routed beneath car
  • 4-Pole flat connector on harness is designed to hook up to your RV's 4-way trailer connector
  • Separate, 3' long harness with 4-way can be wired into tow vehicle or RV if no trailer connector is present
    • Includes quick-splice connectors for simple installation
  • Department of Transportation compliant


Specs:

  • Wiring harness length: 20'
  • Wire length between lights: 4-1/2'
  • Separate wire with 4-way for tow vehicle: 3'
  • Bulb type: 2057 double filament
  • 3-Year limited warranty on housing and wiring only


A towed car is required by law to have functional brake and signal lights that illuminate at the same time as the brake and signal lights on the RV that is towing it. Most wiring kits require you to splice into your vehicle's electrical system to install diodes, but doing this can void your manufacturer's warranty. You also run the risk of making a mistake during installation that could result in potentially damaging electrical feedback. Magnetic tow lights eliminate this problem because they bypass your car's electrical system entirely and leave your wiring intact. Just mount the lights on your vehicle's trunk or roof with the heavy-duty magnetic bases. Then run the wiring harness up to the front of your towed car, across your tow bar, and then connect it to the 4-way flat on your motor home or tow vehicle. If your tow vehicle doesn't have a 4-way, an adapter is required.


This kit includes a 20' long wishbone-style wiring harness with a 4-way flat connector on the end. A separate 3' wiring harness with a 4-way plug can be used to install a 4-way on your tow vehicle or RV if it does not already have a trailer connector. Quick-splice connectors are included if needed. A 4-1/2' long harness connects both lights, giving you enough slack to position the lights where you want them.



TL21RK Optronics Magnetic Mount Stop, Turn, and Tail Towing Light Kit w 20' Wiring Harness

Alternate part number: TL-21RK



This Product Fits The Following Vehicles



California residents: click here


Customer Satisfaction Score:


Customer Reviews

Heavy Duty Magnetic Tow Lights - 20' Wiring Harness with 4-Way Flat Trailer Connector - TL21RK

Average Customer Rating:  4.7 out of 5 stars   (121 Customer Reviews)

Get lights for towing your vehicle without splicing into its wiring. Magnetic light kit provides a pair of stop, turn, and tail lights. Mounts using large, heavy-duty magnets for increased stability. Plugs in at rear of your motor home.

by:
1994 Jeep Wrangler

This lighting kit is just what I needed to pull my Jeep behind my motorhome .
I hooked it up for a test ride and only 1 turn signal worked. When I took the light apart
I found loose wire that was not captured in the wire nut. ( wire nuts are for home construction)
If this item had been built to automotive standards it may have worked without a repair.

I'm not Impressed !




by:

Instructions Chinese vague have to pay someone to hook up lights




by:
2022 Jeep Wrangler 4xe

Saves running wires in the frame. Good product.




by:

Bright with enough wire to go from the rv to the back of the car.




by:
Honda

I am very happy with this purchase. The magnets in the base of the lights keep them connected to the roof of our towed car, no wobbling! The signal wire is long enough to run through our 2019 Honda Fit and connect with our tow vehicle. After getting wet several times, the protective sticker on the bottom of the lights wore off and now the lights have left slight scratches on the roof of the car, nothing major. On the roof of our towed car, they are seen from a distance and work with the tail lights of our motor home just fine.

On occasion, we have to wiggle the wire coming out of the light to get it to work, but this is after a year’s worth of intermittent towing and I’m pretty sure we bashed them around a little. Great product at a great price, professional installation is not necessary. A little better construction and this would be a 5 star rating.




by:
1997 Jeep Wrangler

When I get them ill let you know..


Comments
I see that our customer service department has gotten in touch with you and have set up a UPS claim to find your package. It looks like we have also sent you out one in place of the missing package. Please let me know when you receive your reshipped package.
-- Etrailer Expert Katrina B - 07/25/2022


by:

Used on tow car over the last year - towed at slight angle via tow-dolly. Driven 1000's of miles with this on the tow car through rough storms and strong winds - have not experienced an issue. Strong magnets have not scratched the vehicle. Would purchase again.




by:
1983 Jeep CJ-7

works great for towing my jeep. just plug the four flat into the factory trailer wiring on the tow vehicle, set the lights on the bumper and they work perfect. the magnets are strong but the thicker the metal they are on the better they hold. steel on my bumper is thick enough for a strong hold but I tried thinner metal and the hold is weaker so you may need to add some straps


Comments
one year later and still working perfect
Steelhead - 07/11/2016


by:

Very accommodating and great information research for my situation.




by:
2015 Chevrolet Colorado

All the products I ordered from etrailer,fit and worked excellent for me to be able to flat tow my 2015 Chevrolet Colorado behind our motorhome. I live in Canada and fast delivery on the products I ordered. I will order from etrailer again




by:
Ford Five Hundred

Excellent service, product as promised, little modifications required to fit my Fiat 500.

Only on problem, takes a long time to wait on the phone for customer service


Comments
Fantastic, wiring needs s little workcomments previously sent
Jame W - 07/15/2021


by:

works well




by:
Ford Ranger

Nice magnetic set. I bolted small steel pieces to my ranger bumper because it is covered in plastic. An easy hack located them just wide of the tailgate so it could open with lights in place. Drove 1200 miles with no problems.




by:

Works as designed




by:
2008 Honda CR-V

I am using these for added visibility on the back of a large bike rack that pretty much stays on the car all the time. I do not suggest using the magnets as the only form of attachment as they are not strong enough to keep the lights attached when going over bumps. I zip-tied them to the frame of the bike rack. At first, I had them sticking out from the bottom of the rack, and they were fine until I went up a steep hill and one of the lights got knocked off on the road. These lights are extremely well-built because instead of snapping the light, the rather large zip-ties broke. The light still works great after the incident. I now have them sticking out the sides to give more ground clearance, and they seem to be doing fine. For my application, I had to replace the wire between the lights with a longer one, but that was not difficult and will not be necessary in a typical application. At least the lights are easy to disassemble to access the wiring. The only way these could be improved would be to add strong neodymium magnets and to make the red lenses screw on (instead of snapping on) for easier access to the bulbs for replacement. Otherwise, a perfect product.

For the record, I did not need to use the included vehicle wiring harness or splice connectors, since my application required an electronic light controller.




by:

I got this because the lights on the trailer for my 15' Boston Whaler kept getting broken while launching. Now, I just have to hook these on before I hit the road (easily by magnet) and I can take them off before risking damage while launching. Perfect! Just make sure the wire is long enough. It just fits my little trailer, but a longer one may need an extension wire harness.




by:

The product arrived quickly and was exactly as advertised. The light kit is the perfect solution for the car I tow behind my RV, but also use by itself. I like the fact that it is totally portable, mounts high up on the vehicle for good visibility and is quick and easy to install when needed.


Comments
Worked perfect. I have since gone to anew vehicle with integrated light wiring. I sold the lights to a friend and he has been happy since!
Ed F - 06/09/2018


by:

Perfect, just what we needed to get our trailer home from storage so I could work on the finding the root cause for the failure of the permanent trailer lights. Now that the permanent lights have been fixed, the temporary magnetic lights are stored with the trailer sort of like a spare tire, knowing how fiddly trailer wiring can sometimes be. It's worth the small investment for the extra measure of safety in case the permanent trailer lights fail again far from home.




by:

I purchased a Curt hitch for my 09 CRV. I also bought a wiring harness and a set of magnetic lights for attachment to vehicles. I was able to install the hitch in less than an hour. It took me 30 minutes to connect the wiring. The lights are very simple to connect and only hook up one way. The instructions included links to videos that made the job a snap. The instructions said to put the wiring inside the car by the spare tire when not in use to preserve the connector. what a great suggestion! I did not put a single mark on the car and the hitch looks great.




by:
Jeep Liberty

They say that a company is only as good as its employees... Well, etrailer is extremely fortunate to have someone like Shawn B. Working for them! This young lady got me out of a really frustrating predicament, and through careful listening and asking the right questions, she saved me not only a ton of money, but a whole bunch of frustration as well! My dilemma was that I had purchased a Jeep Liberty with a Blue Ox base plate, but I had a Blackhawk 2 tow bar! I thought I was going to have to go out and buy a Blue Ox tow bar to use with the Blue Ox base plate, but through careful review of my situation, and a calm analytical approach, this young lady determined exactly what I needed in the way of adapters and a towing light set up! Today, more than ever, it's all about customer service, and that is exactly what she provided for me!




by:

The magnets didn't stay on the car so I ended up permanently gluing them to my roof since we tow our car behind the rv full time. Had to replace the bulbs with LED bulbs since our rv tail lights couldn't supply enough voltage to the incandescent bulbs to see them in daytime. This isn't a failure of the product but rather an undiagnosed voltage problem with our rv. With those modifications I am happy with it.




by:

After struggling with my trailer lighting system for years, I gave up and bought a portable system from etrailer. Within 5 minutes of unwrapping it, everything worked great and I am not longer spending hours trying to trouble shoot the old system. The magnets that hold the lights on the trailer are very strong, but I still use a bungy cord on each one just in case I hit a large bump in the road.

Thanks etrailer, excellent product!




by:

Love it, quick and easy! Just great for towing our vehicle behind the RV!


Comments
Works great! No problems!
Nate H - 05/26/2021


by:

etrailer was easy to order from and shipping was fast. However, I ordered this specific light set to fit my standard 4-way flat connection that already exists on my trailer and did not plan on doing any wiring on my truck. Unfortunately, it does not fit. I will have to buy a converter or something I guess. I emailed them with this issue asking if this light is not a standard 4-way flat and haven't received a response.
Seems to be a nice sturdy light set. Doesn't help when I can't use it, though.




by:

So giad I purchased this wiring harness. Works great, is simple to hook up when we're ready to travel. Saved a lot of money since no complicated wiring was required and nothing extra required to hook up.
Love it ... highly recommend.



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Show More Reviews

See what our Experts say about this Optronics Tow Bar Wiring

  • Wire Gauge and Strength of Magnets Used on Optronics Magnetic # TL21RK Towing Lights
    The Optronics # TL21RK Magnetic Mount Taillight Kit uses 18 gauge wires. It would be difficult to quantify the exact strength of the magnets, but I've stuck one of them to a 6 pound trailer drawbar, and found the magnet had plenty of strength to hold the drawbar without coming loose. In other words, the magnet is plenty strong enough to prevent the lamp from being knocked off by wind or turbulence from passing traffic. Keep in mind that the thickness of the metal the magnet is placed on...
    view full answer...
  • Will the Optronics Magnetic Tow Lights Stay On a Vehicle That Travels on Rough Roads
    Yes, the Optronics Tow Bar Wiring # TL21RK uses very powerful magnets. If you hit a bump large enough to knock one of these free you would have much bigger problems to deal with. Check out the review video I attached for more info.
    view full answer...
  • What Circuit for Trailer Wiring Usually Gets Ran to a License Plate Light
    The running light circuit of trailer wiring is what usually gets ran to a license plate light. The brown wire of the # TL21RK carries the running light circuit so this would be the correct circuit to use. I attached an FAQ on trailer wiring for you to check out as well.
    view full answer...
  • Will Wireless Flat Towing Lights Work with Portable Supplemental Braking System
    Yes, the magnetic tow lights part # TL21RK will work just fine with a portable supplemental braking system on your 1996 Jeep Grand Cherokee. The two systems will work just fine independently of each other.
    view full answer...
  • Where is Brake Light Circuit Found on Truck Near Rear of Vehicle
    If you are looking for a circuit that carries only a brake signal you can try a third brake light circuit as that's typically the easiest place to find that circuit near the rear of a vehicle. For a set of towing lights you could use the magnetic kit part # TL21RK for an easy solution.
    view full answer...
  • What Gauge Wire Does the Heavy Duty Magnetic Tow Lights Part # TL21RK Use
    I spoke to my contact at Optronics and they informed me that the Heavy Duty Magnetic Tow Lights part # TL21RK uses a 20 gauge wire. This will be standard for most magnetic tow lights for the exception of a few which can use an 18 gauge wire but that would be the thickness wire used in a set of magnetic tow lights.
    view full answer...
  • Should Overdrive Be On When Towing Travel Trailer with Ford F250 Diesel
    As long as your F250 seems to be handling everything okay and is staying in overdrive (not continuously shifting in and out of overdrive), towing your 9,500 pound travel travel with it on should be perfectly fine. It is recommended to turn it off while driving up or down hills or through heavy traffic, which you have been doing, so you should have no issue with this at all. It may also be a good idea to take a look at your vehicle's owner's manual, as there may be some towing recommendations...
    view full answer...
  • Are Towed Vehicle Lights Required to be Active when Being Dolly Towed
    Typically the lights on a vehicle being towed on a dolly don't have to be active, but it is always best to check with local authorities to ensure that you are abiding by the dolly towing laws. With that being said, some people still prefer to install magnetic towing lights on their towed vehicle just to make sure that everyone around them knows what is going on. The Heavy Duty Magnetic Tow Lights # TL21RK are a very popular kit that we carry and they come with a small pigtail that you...
    view full answer...
  • What Gear Does a 2002 Toyota Highlander Need to be In While Dolly Towed
    According to the owner's manual for your 2002 Toyota Highlander, you will need to place the vehicle's transmission into neutral "N" and leave the key in the accessory "ACC" position when towing the vehicle with a dolly. I recommend taking a look at this for any other information you need to follow when the vehicle is in tow. Please keep in mind that the vehicle will need to have signals coming from it even on a tow dolly unless the tow dolly itself has the signal lights. If it does not...
    view full answer...
  • Is There a Plug and Play Flat-Tow Wiring Harness for a 2018 Jeep JL Wrangler Unlimited
    I do have options for you but they do not make a plug and play flat-tow wiring harness for your 2018 Jeep JL Wrangler Unlimited at this time (July 2018). However, that is not to say that there will not be one in the future as it is a relatively new vehicle therefore, I recommend using the Heavy Duty Magnetic Tow Lights part # TL21RK until a plug and play flat-tow wiring harness is available for your vehicle. The Magnetic Tow Lights are an excellent option for nearly every vehicle. They...
    view full answer...
  • Flat Towing Harness for 1994 Jeep Wrangler YJ Towed Behind 1996 Ford RV
    The wiring used to allow a vehicle like your Jeep YJ to tow a trailer is not the same as what is required to tow that vehicle behind an RV. On the linked page you can view all flat towing wiring kits for your 1994 Jeep Wrangler YJ. These include bulb-and-socket, diode and magnetic light kits like # TL21RK, by far the easiest to use of the three types. You can refer to the linked articles for more information on each type of kit.
    view full answer...
  • Hitch-Mount Cargo Carriers for the 2012 Honda Accord That Can Carry 250-lbs
    We offer a number of hitch receivers for the 2012 Honda Accord. For reference, the link provided will take you to our main page for all hitches for your vehicle. All of these hitch receivers share a 1-1/4-inch receiver size and a Class I weight rating. All also share a 200-lb tongue weight capacity. Tongue weight is the measure of the downward force applied on a hitch by whatever is connected to it, be it a trailer or a cargo carrier. In your case this 200-lb limit must include the weight...
    view full answer...
  • How Strong are the Mounting Magnets on Optronics Towing Lights # TL21RK
    Describing the strength of the magnets used on the Optronics Magnetic Mount Tail Lights would be fairly difficult, as magnet strength is pretty subjective. The magnet on one of the lamps is strong enough to suspend a 6 pound ball mount, as you can see by watching the short video I produced for you. Hopefully, this will give you an idea of how strong the magnet is. The thickness of the metal the magnetic light is attached to will also have a bearing on how well the magnet adheres to the...
    view full answer...
  • Looking for Replacement Magnetic Mount Trailer Light
    We offer the Heavy Duty Magnetic Tow Lights, # TL21RK, which provides a pair of stop, turn, and tail lights and is compliant with the Department of Transportation. Unfortunately, the magnetic lights are not sold individually.
    view full answer...
  • Do Magnetic Tow Lights Attach to To Tow Vehicle or Vehicle being Flat Towed
    Magnetic tow lights used when flat towing actually attach to the rear of the vehicle be flat towed and not the RV like you mentioned. So you'd attach magnetic tow lights like the part # TL21RK to the roof or bumper of your 2017 Ford Fusion instead. See picture attached.
    view full answer...
    Image 1 for
  • Magnetic Trailer Lights Bleed Into One Another When Using Turn Signals
    If you have a signal bleeding from one light to the only then you have some sort of a wiring short. The first thing you will need to do to find this short is test the trailer connector on the tow vehicle. In order to do this you will need to activate one of the turn signals and then test both pins. If you get voltage on both pins then you know the issue is on the vehicle side. If you only get voltage on the correct pin while that respective signal is active then you know the issue is on...
    view full answer...
  • Troubleshooting Heavy Duty Magnetic Tow Lights Turn Signals
    The Heavy Duty Magnetic Tow Lights - 20' Wiring Harness with 4-Way Flat Trailer Connector # TL21RK should not have turn signals flash on both sides. It sounds like there is a short inside the unit since you have tried it on multiple vehicles. You can see in the attached video that the turn signals should operate independently. It sounds like there is a short circuit connecting the two sides.
    view full answer...
  • Trailer Taillights Not Working Correctly and Error Lights Displaying on Dash of 2021 Ford F150
    There's something in the taillight/brake circuits of the trailer that the computer on the F150 doesn't like. I'd recommend closely examining the wiring on the trailer, look for loose connections or pinched wires. One of the circuits on the trailer has too high or tow low of a resistance on it, and the Smart Towing system on the truck doesn't like it. You'll also want to check the connector on the trailer. A corroded or damaged trailer connector can also cause this occurrence.
    view full answer...
    Image 1 for
  • Can Heavy Duty Magnetic Tow Lights be Used with Sprinter RV
    The LED resistor requirement your Sprinter has would be related to replacement vehicle taillight wiring and not if the trailer wiring/tow bar wiring was LED like the # TL21RK. So you would not need to use any resistors with this kit. Also this kit uses incandescent bulbs and not LED.
    view full answer...
  • How to Add Magnetic Lights to Vehicle on Tow Dolly
    You can certainly just splice the harness from the magnetic lights to the appropriate light circuit wires on your tow dolly instead of adding a new plug on the RV. This setup would activate the magnetic lights just the same as running the wiring to the RV. To do this I recommend the Optronics # TL21RK that includes a separate 3 foot long 4-Way extension so that you can easily splice into the wires. I have attached a short video demonstration on this kit that you can check out as well.
    view full answer...
  • Does Heavy Duty Magnetic Tow Lights # TL21RK Have Running Taillight Function
    The Heavy Duty Magnetic Tow Lights # TL21RK that you referenced do cover the taillight function as well as the stop/turn functions. I attached a review video for this for you to check out as well.
    view full answer...
  • Explaining Wiring Connections on Yellow and Brown Wire of Tow Ready Tail Light Isolating Diode
    I found the portion of the install video of the # TR118821 that you mentioned and to clarify what he's doing he's splicing in the wiring from the kit to the wiring of the vehicle in a way that allows the vehicle wiring to still function like it needs to and also allow the converter box to get the signal it needs to from the circuits. So he's cutting the vehicle wiring and putting the vehicle wiring and the converter box wiring in one end of the butt end connector and then the other end...
    view full answer...
  • What is Gauge of Wire in Heavy Duty Magnetic Tow Lights # TL21RK
    The gauge of the wire in the Heavy Duty Magnetic Tow Lights # TL21RK is 18 gauge so it would be what you are looking for.
    view full answer...
  • Can Magnetic Tow Bar Light Kit be Used to Move Trailer Temporarily
    Yes, you could use the Heavy Duty Magnetic Tow Light part # TL21RK as an easy way to transport a trailer without trailer lighting. You'd just plug in the 4-way and then mount the assemblies on the fenders or anywhere else visible and you'd be set.
    view full answer...


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