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Curt Trailer Breakaway Kit with Trickle Charger, LED Tester, and 5 Ah Lead Acid Battery - Side Load
CURT

Curt Trailer Breakaway Kit with Trickle Charger, LED Tester, and 5 Ah Lead Acid Battery - Side Load

Part Number: C52042
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$63.14
Retail:$96.19
You Save: 34%
Trailer Breakaway Kit
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Lead-acid batteries require no maintenance, which is why we love this kit. The built-in charger keeps the battery charged and ready to bring your single-, tandem-, or triple-axle trailer to a complete stop. LED tester lets you check the charge. Great Prices for the best trailer breakaway kit from CURT. Curt Trailer Breakaway Kit with Trickle Charger, LED Tester, and 5 Ah Lead Acid Battery - Side Load part number C52042 can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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CURT Trailer Breakaway Kit - C52042

  • Kit with Charger
  • Single-Axle
  • Tandem-Axle
  • Triple-Axle
  • Battery Included
  • Side Load
  • Electric
  • 5 Ah
  • CURT
  • LED Indicator
  • 51 Inch Long

Lead-acid batteries require no maintenance, which is why we love this kit. The built-in charger keeps the battery charged and ready to bring your single-, tandem-, or triple-axle trailer to a complete stop. LED tester lets you check the charge.


Features:

  • Makes sure your trailer safely stops if it separates from your vehicle
    • When the pin gets pulled from the switch, a signal is shot back to your trailer brakes to activate
    • Lead-acid battery works great in high temperatures
  • Automatically charges battery with the built-in charger when connected to your vehicle
    • Won't overcharge the battery
  • Lets you test battery status with the push of a button
  • Mounts on the outside of your trailer's frame
    • Side-loading case provides easy access to the battery
    • Switch installs on your trailer's frame with included self-tapping screws
  • Protects battery from rain and debris with durable, plastic case
    • Lid can be secured with padlock (sold separately) to deter battery theft
  • Includes breakaway switch, charger, Lead-acid battery, battery box, wiring, and mounting hardware
  • Department of Transportation (DOT) compliant


Specs:

  • Application: single-, tandem-, and triple-axle trailers with electric brakes
  • Battery capacity:
    • Voltage:12V
    • Type: sealed lead-acid
    • Capacity: 5 amp-hours
  • Breakaway cable length: 51"
  • Breakaway switch:
    • Dimensions: 4-3/8" long x 1-1/2" wide
    • Lead wire length: 24"
  • Charger lead wire length: 12"
  • Battery box dimensions: 6" long x 3-3/4" wide x 5" tall
    • Battery case mounting holes:
      • From center to center vertically: 3-1/4"
      • From center to center horizontally: 5-1/2"
  • 1-Year limited warranty


Note: A breakaway system is required by law in most states for trailers that are equipped with electric brakes and have a GTW of at least 3,000 lbs.


Built-In Battery Charger and Tester

The integrated charger keeps the included battery charged and ready to go. At any time, if you would like to see what the state of the rechargeable battery is, just push the green button and LEDs will light up to indicate the battery's status. If it's green, it means the battery is fully charged. Yellow shows it's currently charging, and red indicates a low battery.


Image of LED indicator showing the status of your battery

Quick Tips:

  • When you store your trailer, be sure to keep the pin plugged into the breakaway switch. If the pin's removed for an extended period of time, dirt and moisture can get into the switch and cause corrosion that could keep it from activating when you need it.
  • A breakaway system needs to be able to apply the trailer brakes fully for at least 15 minutes. In general, the heavier your trailer, the higher amperage battery you'll need for the breakaway.


52042 Curt Side Load Push-to-Test Break Away System with Lockable Box

Installation Details C52042 Installation instructions



Customer Satisfaction Score:

Ratings & Reviews

4.6

233 reviews
Review sort icon
Lead-acid batteries require no maintenance, which is why we love this kit. The built-in charger keeps the battery charged and ready to bring your single-, tandem-, or triple-axle trailer to a complete stop. LED tester lets you check the charge.

by:

I just opened up my new Class 5 Curt XD hitch and have not yet installed it so my comments are based on first impressions only. It is very heavy duty - and heavy at 40 lbs. - made of extremely thick metal and outfitted with quality Grade 8 bolts with square necks so they won’t turn when torquing on the nuts to attach the main tube to the side mounting plates. My bolts are plated yellow (which I like) rather than silver as you may have seen in some online photographs. It is substantially beefier than my existing Grade 4 hitch and superior in every way. It’s an impressive piece of hardware. I cannot imagine anyone being disappointed with it on specifications, quality, strength, and general appearance. It’s a beast. What I AM disappointed in is Curt’s packaging and the condition in which the hitch arrived. (This is NOT a reflection on etrailer.com as the hitch arrived in Curt’s original packaging.) The unassembled main tube and the two side mounting plates come bundled together with nothing separating them but shrink wrap. No cardboard, plastic, even paper coming between the metal surfaces - just shrinkwrap probably not even a couple of mils thick. With basically metal-to-metal contact in an oversized-box with the bundle jostling around, it would be a miracle if there were no scratches, gouges, or some type of damage to at least one piece, which is exactly what happened to my hitch. The main hitch tube, on the exterior facing plane, on the driver side where I’ll see it every day, has some gouges on it that go through the powder-coating to bare metal. I can - and will - paint them to prevent rust (and, therefore, have to paint the whole hitch to match). But the gouges will still be noticeable as they go through the thicker, pebbly, powder-coat finish and will undoubtedly still appear as depressions in the surface even once painted. I fully realize this kind of surface damage will almost certainly happen with regular usage of the hitch anyway and that it’s certifiable to demand absolute perfection in anything. But if you are someone who cares about the aesthetics of your equipment and keeping it looking new for as long as possible, it is very disappointing to receive such an expensive and prominent piece of hardware damaged right out of the box and requiring immediate repainting. The plastic parts bag had also ripped open in transit, with nuts, bolts, shims, etc. rattling around in the box. I am dumbfounded that Curt packages such a high-quality piece of equipment so shoddily where such damage is virtually unavoidable. I bought from Curt solely due to their being an American manufacturer and to support American workers so this is doubly discouraging. It’s a trivial complaint in the big scheme of things and not worth demanding a replacement over. Just be aware that unless Curt changes their packaging practices it is very possible you will have the wind taken out of your towing project sails just as I have. Again, this in no way reflects on etrailer. My experience to date with etrailer (website, educational resources, staff reviews, ordering, tracking, email contact, etc.) has been beyond exemplary in every way. They rank as a Top Five online retailer in my opinion, maybe even the best.



by:

Great product to use when swapping out the old surge brake system for a new electric system. Only needed to buy wire and waterproof connectors and I was set.



by:

Product seems to work however the instructions that came with it had the correct part number but the wiring diagram was wrong. I contacted etrailer and they confirmed that and emailed me a more current diagram which was also wrong. I contacted curt and the first tech told me there was a wiring issue with my trailer. Finding none I called again and was told the first tech was wrong. Then I noticed the diagram on the control cover and it is correct and seems to be working. Called curt again and they said they are looking into the instructions issues.



by:

Replaced a outside rail unit on my Trailex enclosed (1999) with this unit, but moved it inside by winch mount to better protect from elements. 1 year in, start of new towing season, still working as designed (brake engage), charging off of tow vehicle 12v power from 7-pin cable source.

Would buy again to replace a dead battery, to all new accessories, not a place to scrimp.



by:

Product is great quality and all but the only issue i have is the wiring diagram for a diyer is horrid. Still havent figured out how to wire it. 2 blue wirs and a black and nothing about where they go. After 2 sparking incidents and killing the battery i gave up trying to install

Heather A. profile picture
Etrailer Expert

Heather A.

8/14/2024

Hey man I totally get it. Wiring diagrams are not my thing either. I recommend to look the installation video I posted because David explains it step by step.



by:

Excellent, high quality kit. The instructions are poor. White goes to ground, blue goes to the black emergency disconnect wire, with the other blue emergency disconnect wire going to the blue (e-brakes) junction. Red goes to the 12v junction (black).



by:

The state of charge indicator light for the battery is reassuring when you connect to the trailer. Trailers do need to stop if they ever become disconnected from the tow vehicle, and this lets you know you have the power to do just that.



by:

Lauren was very helpful, fast delivery



by:

Have not recieved yet



by:

worked as intended



by:

Product as described. Wiring instructions from MFG not exactly correct- as referes to 2 black wires from break away switch. There is a blue wire and a black - blue wire color matches with internal wiring from box.



by:

Works as it should …



by:

A real great quality product. Unfortunately weather/time has not allowed me to get it installed. Thank you for the availability of this product.



by:

The product is fine the paper that comes with it does not match. One extra piece in the picture. Wiring diagram dose not match the product. Should be the following.The white wire is ground (-). The blue wire is positive (+) for the brakes/breakaway switch. The red wire is for the charging circuit (12v Aux Power) in your connector.There is no yellow wire in the push to test panel.I would give it a 5 star if the paper work was ok.



by:

Great price.



by:

This is a product that I hope I never have to use! It arrived sooner than I expected. Packaging was great, no damage. I did have an issue with the instructions that came in the box. It showed two black wires coming from the battery/charger box, instead of a red, white, and blue. Went on line a was able to print out the correct wiring diagram. The other thing that the instructions said was to use a 9/32 drill bit for the mounting screws. I drilled the first hole and the screw went right through the hole. Should use a 7/32 drill bit. All in all, very happy with the product. Have bought from etrailer four or five times, have been happy every time. Will buy again when I need something else

Bruce profile picture

Bruce

3/21/2025

Still fortunate enough not to have had to use it! Trailer doesn’t get used that often, and sometimes the battery goes dead between usage, but charges back up when used.

Jerred H. profile picture
Etrailer Expert

Jerred H.

3/21/2025

@Bruce That's great to hear! What kind of trailer do you have?


by:

Replace old one with this worked out good



by:

the battery box mounting holes matched the holes already in the trailer (tandem axle gooseneck utility), so that saved some effort. the hole spacing on the short side is 3 1/4", not 3 1/2" indicated in the image on the website. perfect replacement for the original breakaway system when the trailer was purchased new 8 years ago.



by:

worked out great.



by:

I replaced an existing backup battery and break-away switch and this product installed easily and works well. The info on the product page really helped me find what I needed.



by:

Quality built, easy installation instru ctions



by:

Very fast shipping. Product was easy to install



by:

The included instructions were helpful, and it had all the mounting hardware needed. Thanks for a great product. I installed this along with new brakes as well. The whole package went on it's first trip in who knows how long.



by:

Well, I'm knocking off two stars because of all the time spent researching the CORRECT wiring diagrams! The one that comes with it is NOT the correct instructions or diagram for this battery. The Battery and test feature and breakaway switch are all well built, but not even eTrailer is getting the problem addressed adequately about the wiring diagram. Fortunately, someone mentioned finding the correct manual and diagram (even it has flaws) on line. Between three different manuals and diagrams I think I'm figuring it out, but it has taken me several hours to do this.



by:

During the upgrade of my dual-axle, 4500-lb trailer to disc brakes and "electric over hydraulic" acutator, I needed to install a breakaway kit on the trailer tongue. The Curt Trailer Breakaway kit fit the dimensions and the 5Ah battery provides enough power to actuate the EOH system.


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See what our Experts say about this CURT Trailer Breakaway Kit

  • Should Battery Be Disconnected When Relocating Break Away Switch?
    Hi Jeff! A break away switch, like the Curt Trailer Breakaway Kit # C52042, basically just completes a circuit that then powers the electric brakes. If you are removing it to relocate the switch and or trailer, you will want to completely disconnect the battery from the trailer. That way there is no way it can supply power to the brakes. Where is it now and where are you wanting to relocate it to?
    view full answer...
  • Adding Brakes To A 1998 Starcraft Pop Up Camper
    I am happy to help set you up Rafael. In order to add brakes to your 1998 Starcraft pop up camper, the axle must have a brake flange attached behind the hub assembly on each side. If the current axle does not have a brake flange you can either replace the axle entirely, or you can have a brake flange welded to the axle. Generally replacing the axle is our preferred method, since welding on brake flanges requires special equipment and it can be expensive. If you want to look into replacing...
    view full answer...
  • Can Trailer Breakaway Kit Be Installed Into Junction Box for Cleaner Connections
    Sure, if you want to install the breakaway kit through the junction box, you would just need to make the connections that would normally run to the wiring harness, into the respective terminals inside the junction box. While we don't have a video to show how this is done, you can use the attached diagram that I've put together for you. For a junction box, I recommend part # 38656 and for a breakaway kit, I recommend the Curt Push-To-Test Trailer Breakaway Kit with Built-In Battery Charger...
    view full answer...
    Image 1 for
  • Comparing Trailer Breakaway Switch Kits
    Some different brand names of trailer breakaway kits do originate from a common source, and this is also true for items like jacks, landing gear and steps. There really is not a lot to distinguish one from another, since their component parts are virtually identical: a battery, a box, a charger and a switch. The one part that can make a difference is the battery itself. A higher output battery can power brakes on more axles. Hopkins Engager Trailer BreakAway Kit # 20400 can handle 1 or...
    view full answer...
  • Breakaway Kit Not Working Properly and Causing Issues with my Brake Controller
    If I understand correctly when you hit the brakes in your truck the trailer brakes work fine. Then if you pull the pin on the breakaway switch the trailer brakes do not work and will not work again even using the truck until you put the pin back in the breakaway switch. If this is the case there is a wiring problem with your breakaway kit the main trailer brake wire should run directly to the brakes and the breakaway kit should only be spliced into that. It sounds as though the trailer...
    view full answer...
  • Mounting Hole Pattern of Curt C52042 Push to Test Trailer Break Away System Battery Box
    I had one of the # C52042 push to test break away kits pulled from inventory, and found that the bolt pattern of the # C52042 measures 5-1/2 by 3-1/2 inches. I've linked though our in-stock systems and haven't found a push to test break away kit with the same 3 x 4-1/2 bolt pattern as the # C52040. However, since the # C52042 is larger, you could simply fasten it to the trailer frame by drilling through the bottom of the battery box, if you're reluctant to drill new mounting holes into...
    view full answer...
    Image 1 for
  • How To Wire the Curt Push-To-Test Trailer Breakaway Kit
    In regards to the Curt Push-To-Test Trailer Breakaway Kit part # C52042, the blue wire on the breakaway switch will be run to the brake output circuit and the black wire to a constant 12 volt power source. The blue wire on the battery box will also will be run brake output circuit, the red wire to a 12 volt power source, and the white wire to a ground.
    view full answer...
  • Troubleshooting Install of Curt Breakaway Kit on Trailer Where Brake Lock Up
    Since your trailer doesn't use standard colors for it's wiring for lighting and braking you are going to have to wire in the breakaway kit # C52042 by function instead of by color. I won't be able to tell you which color is which on your trailer as you'll have to determine that by either tracing the wiring or using a jumper wire from a car battery to first determine all of the functions. So the red wire of the # C52042 needs to connect to the 12 volt accessory circuit of your trailer wiring....
    view full answer...
    Image 1 for
  • Trailer Breakaway Kit that Can be Used with Tandem Axle Trailer
    Hey Bryce, the Curt breakaway kit part # C52042 would work great on your dual axle flat bed trailer. This kit is rated for up to three brake axles so your tandem axle setup would work great.
    view full answer...
  • How To Wire the Curt Push-To-Test Trailer Breakaway Kit C52042
    In regards to the Curt Push-To-Test Trailer Breakaway Kit part # C52042 (52042), the blue wire on the breakaway switch will be run to the brake output circuit and the black wire to a constant 12 volt power source. The blue wire on the battery box will also will be run brake output circuit, the red wire to a 12 volt power source, and the white wire to a ground. Unfortunately, we do not create any of the wiring diagrams for Curt as they are the manufacturers.
    view full answer...
  • Does Charging Battery of Curt Breakaway Kit # C52042 Take a Long Time
    To charge a battery through the 12 volt accessory circuit of a vehicle and trailer wiring does take some time. If the battery was in a pretty low state of discharge it would not surprise me that it's still charging. If you wanted to charge the battery quickly you'd need a charger that plugs into a wall outlet like the part # CTEK56353.
    view full answer...
  • What Breakaway Device Do You Recommend for My 2021 Jayco Travel Trailer?
    As far as the cables/plugs that come with breakaway systems, they are virtually universal for trailers. As far as a great breakaway system for your 2020 Hay Flight 29RKS, the breakaway options depend on where you want to mount the switch. For the best options, I recommend the Bright Way Push-to-Test Trailer Breakaway Kit with 1-Amp Charger and 5 Ah Battery # 3802308 (top loading) or the Curt Push-To-Test Trailer Breakaway Kit with Built-In Battery Charger # C52042 (side loading). Both of...
    view full answer...
  • Can Roadmaster Diode Be Installed to Prevent Curt Breakaway Battery From Draining Onboard Battery
    Thanks for all of the information about what you're experiencing with the Curt Push-To-Test Trailer Breakaway Kit # C52042. I'll address your questions in the order you asked them: 1 - The built-in battery charger that comes with the breakaway kit will prevent it from overcharging. 2 - Using the Roadmaster Single Park Light Diode # RM-690 is an excellent way to prevent back feeding like that you mentioned. 3 - The application is pretty simple and effective so there isn't anything else...
    view full answer...
  • Best Breakaway Kit with Push To Test Feature for Triple Axle Trailer
    I do have an option for you but the Hopkins Engager Push-To-Test Trailer Breakaway Kit w/ Built-In Charger part # 20099 is only rated for use on single and tandem axle trailers. For a breakaway kit that is rated for use on triple axle trailers you will want to use the Curt Push-To-Test Trailer Breakaway Kit with Built-In Battery Charger part # C52042. The Curt breakaway kit as the title suggests also has a built-in push to test feature as well as a side load battery box just like the Hopkins...
    view full answer...
  • Is There a Curt Soft Trac Breakaway Kit that Has Battery Charge Indicator
    If you are looking for a similar trailer breakaway kit that has a built in charger and tester we have the Curt part # C52042 which will show you when it's charging and charged but the part # C52040 that you referenced does not have this feature.
    view full answer...
  • Determining If Electric Trailer Brakes Can Be Added to 2021 Anvil 6 x 12 Cargo Trailer
    I would be happy to help. To add electric trailer brakes to the 2021 Anvil 6' x 12' Cargo Trailer you mentioned you will need to do is verify that behind the idler hub is a brake mounting flange as shown in the included picture. If one is there brakes can be added pretty easily, and if one is not there brakes can still be added, but it will be a bit more work. If no brake mounting flange is installed you will need to have one installed. I was able to find that the Anvil 6' x 12' includes...
    view full answer...
    Image 1 for Image 2 for
  • Where to Attach Cable for Curt Push-To-Test Trailer Breakaway Kit
    The most common method for attaching the cable for a breakaway kit like the Curt Push-To-Test # C52042 that you referenced is feeding it through the safety chain loop on the trailer hitch. The warning message that you mentioned on the instructions manual caught me a little off guard so I called my contact at Curt and he actually said that "mounting hooks" in that statement refer to the hooks on the safety chains themselves. He said that the cable can absolutely be connected to the tow...
    view full answer...
  • Determining Correct Components To Replace Hydraulic Surge Brakes W/ Electric Brakes
    I would be happy to help! Based on the information of your current hub and drum assembly using Braking Assemblies # T1878800 and Grease Seal # 168233 that tells me that your axle more than likely uses standard 3500lb hub and drum assemblies. You will need to confirm this by removing one of your hubs and look for the bearing numbers stamped in the face of each bearing as shown in the included picture of the # L44649. If your bearings are worn to the point that you cannot read the bearing...
    view full answer...
    Image 1 for Image 2 for
  • How To Move A Trailer With A Dead Breakaway Battery
    On most breakaway kits such as the Hopkins Brake Master part # HM20001, you will not need to cut or splice any of the wires to move the trailer with a dead battery. If your power supply is not active, then the only effect is that the breakaway system will not send power to your trailer's brakes in a breakaway situation thus allowing for free movement of the trailer. Even if the battery is dead, the brake controller will still allow you to activate your trailer's brakes To prevent further...
    view full answer...
  • Curt Push-To-Test Trailer Breakaway Kit Access Lid Orientation
    The Curt Trailer Breakaway Kit # C52042 is a side load design and only intended for that orientation. You will want to use Curt Trailer Breakaway Kit # C52044 for your application to have the access lid facing up.
    view full answer...
  • Troubleshooting Trailer Brakes Randomly Applying
    Hey Daniel, I would be willing to bet that your issue is a short between the 12 volt accessory circuit wire that runs to your trailer battery and the brake output circuit which carries the voltage to the assemblies. What is most likely happening is there is some exposed wire between the two circuits intermittently making a connection. This is most likely at the back of the new trailer wiring connector you installed so that would be what I would check.
    view full answer...
  • Should Breakaway Switch be Wired to Auxiliary Battery
    It sounds like your breakaway switch is wired to your auxiliary battery, which is not something that should be done, and can explain the backfeeding (which also should not be occurring). So what you will need, and something that is required by law in many states, is a breakaway kit with its own dedicated battery: - Curt Push-To-Test Trailer Breakaway Kit with Built-In Battery Charger # C52042 I have added a link below to a video review for you to check out as well of this kit.
    view full answer...
  • Brake Away Switch And Battery Disconnect Compatibility
    The breakaway for your trailer should have it's own dedicated battery like the Curt Push-To-Test Trailer Breakaway Kit with Built-In Battery Charger Item # C52042 does. The built in battery charger receives power from your 7-way connection to recharge the battery so you won't be hooked up to the trailer's battery at all and won't have any issues with your battery disconnect switch.
    view full answer...
  • Is Bright Way 3802311 Trailer Break Away Kit Compatible with Triple Axle Trailers
    According to Curt, their # C52042 Trailer Breakaway Kit is compatible with single, tandem or tri axle trailers. I've inked to a product demonstration video that you might find helpful.
    view full answer...


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Info for this part was:

Employee Mike L
Expert Research:
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Employee Lindsey S
Edited by:
Lindsey S
Employee Jeff D
Installed by:
Jeff D
Employee Cole B
Installed by:
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Employee Robert C
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Employee Joshua S
Video Edited:
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Employee Kathleen M
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Employee Chris R
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Employee Chelsea B
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