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Roadmaster Battery Charge Line Kit for Towed Vehicles

Roadmaster Battery Charge Line Kit for Towed Vehicles

Item # RM-156-25
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RM-156-25 - Battery Charge Line Kit Roadmaster Accessories and Parts
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Kit allows up to 15 amps from your RV's battery to be used to maintain the charge of your towed car's battery while the car is being towed. Charge line connects to the 6-way or 7-way plug on your vehicle. Requires separate charge line in RV. Call 800-298-8924 to order Roadmaster accessories and parts part number RM-156-25 or order online at etrailer.com. Free expert support on all Roadmaster products. Guaranteed Lowest Price and Fastest Shipping for Roadmaster Battery Charge Line Kit for Towed Vehicles. Accessories and Parts reviews from real customers.
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Roadmaster Accessories and Parts - RM-156-25

  • Tow Bar Wiring
  • Battery Charge Line Kit
  • Roadmaster

Kit allows up to 15 amps from your RV's battery to be used to maintain the charge of your towed car's battery while the car is being towed. Charge line connects to the 6-way or 7-way plug on your vehicle. Requires separate charge line in RV.


Features:

  • Maintains the battery charge in your towed vehicle while the car is being towed
    • Provides just 15 amps to avoid overcharging
  • Connects battery to 6-way or 7-way plug at the front of your towed car
  • Receives power from your RV
    • Requires Roadmaster's motor home battery line (RM-156-75 - sold separately) if no charge line is present in your RV
  • Includes 14-guage wire, split wire loom, circuit breaker, and hardware
  • Made in the USA
  • Limited Lifetime Warranty


156-25 Roadmaster Battery Charge Line Kit for Towed Vehicles






Customer Reviews

Roadmaster Battery Charge Line Kit for Towed Vehicles - RM-156-25

Average Customer Rating:  4.8 out of 5 stars   (125 Customer Reviews)

Kit allows up to 15 amps from your RV's battery to be used to maintain the charge of your towed car's battery while the car is being towed. Charge line connects to the 6-way or 7-way plug on your vehicle. Requires separate charge line in RV.

- RM-156-25
by:

I installed this baseplate on my 2003 Honda CRV myself. It was a challenge for an inexperienced mechanic but successful in spite of that. Following the clear instructions, the unit fit well into the CRV chassis. Installing it myself has also given me confidence in towing that I may not have had by giving that task to someone else. I wired the CRV and RV 6 way and 7 way connectors including power to charge the CRV's battery while towing. After towing the car for several thousand miles, I am very satisfied with the base plate, tow bar, and installation. 681269



- RM-156-25
by:

I have a battery charger cable from my RV to the towed car. My battery is in the rear so the instructions state I can attach the wires to the battery connector points up front. But then it says to attach the charger thing as close to the battery as possible. Question - Do I put the charging thing in the rear or the front 582538


Comments
According to Roadmaster, its best to install the circuit breaker which is the small box with the two terminals on it that I believe you were referring to as close as possible to the battery.
-- Mike L - 11/15/2018

45748

- RM-156-25
by:

Ordered 3 parts: RM-156-25; RM-156-75 and DW05745-10. All received very quickly, as is the case when I purchase from etrailer. More importantly, I get a 'live person' when I call for assistance and the service rep. is always knowledgable ( not an answering service that "will have someone call back". Time was spent with me answering all my questions and providing suggestions and opinions when I as for them, related to my project. Great company, great service - keep up the great work! 693892



- RM-156-25
by:

The product was exactly what I needed to keep the battery of my towed vehicle charged and it was very easy to install.I would recommend it for everyone that has a motor home and a tow vehicle. 544210



- RM-156-25
by:

this does not isolate your battery from feeding back into your motorhome, this is simple a circuit breaker with a piece of wire and connectors. if it was a real kit it should have a protective diode to insure issues in the towed vehicle do not interfere with the charging system in your motorhome, as it is this is just a jumper between the alternator/battery in the motorhome and the alternator/battery in your towed vehicle. 477658



- RM-156-25
by:

OK...did the job, but kit should include diode block. 682693



- RM-156-25
by:

938128



- RM-156-25
by:

Orders are complete and all things you would need are included. Videos are very helpful. I only use etrailer 935827



- RM-156-25
by:

This was an easy install. etrailer is the most helpful company I have ever dealt with. We are just setting up a Jeep Wrangler for towing so we are learning as we go at the DIY. Bailey was great with her knowledge and helpfulness. 935449



- RM-156-25
by:

They where very helpfull and Recommend a trailer very highly 934936



- RM-156-25
by:

Received today weather permitting will install tomorrow 933969



- RM-156-25
by:

923950



- RM-156-25
by:

923205



- RM-156-25
by: 12/06/2020

920146



- RM-156-25
by:

Works without a problem! 916022



- RM-156-25
by: 11/22/2020

A little pricey, use on a 2014 CRV, battery stays up good when being towed 915171



- RM-156-25
by: 11/19/2020

No problems charging works great. 913975



- RM-156-25
by:

Just received my order, Once again, very fast shipping!!! 913178



- RM-156-25
by:

The kit was easy to install and has performed flawlessly. 911528



- RM-156-25
by:

Easy to install and will work with my v ehicle. 909828



- RM-156-25
by:

installation instructions were clear and very helpful, recommended if using a supplemental braking system to avoid having a dead battery in your tow vehicle when you arrive, also the possibility of your braking system and brake lights not working during travel 909485



- RM-156-25
by:

Always excellent products and follow up service. 908300



- RM-156-25
by:

Good product. etrailer’s install video was spot on! 906929



- RM-156-25
by: 10/29/2020

905475



- RM-156-25
by:

2020 Ford Escape. Easy to do yourself! 902926


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Ask the Experts about this Roadmaster Accessories and Parts

  • How to Keep Battery Charged While Flat Towing a 2015 Fiat 500
    Great question! From what I could find in the owner's manual for a 2015 Fiat 500 (looking both at the Recreational/Flat Towing and Emergency Towing procedures) it does look like you need to keep the steering wheel unlocked while flat towing. Since this means your ignition is on, it can very well drain your battery. I'm not sure why this isn't something that is commonly known because even some of our flat towing manufacturers don't have this info on their site. I reached out to Roadmaster...
    view full answer...
  • Recommended Charge Line for Toad Behind Motorhome
    The battery of your 2015 GMC Yukon must be disconnected to protect your electronics when towing. If your supplemental braking system uses power, then I recommend the Roadmaster Battery Charge Line Kit for Towed Vehicles # RM-156-25 on your vehicle. If you don't have the charge line on your 7-way or 6-way of your motorhome, then I recommend # RM-156-75 for that charge line kit. To make disconnecting and reconnecting your Yukon battery easy, I recommend the Roadmaster Automatic Battery...
    view full answer...
  • How to Install Battery Charge Line Kit on 2018 Chevy Equinox While Using Blue Ox Patriot II
    While I can't give you a definitive answer as to how your shop chose to wire in the 12V accessory plug on the dash of your 2018 Chevy Equinox, I can say that it is highly unlikely that it's wired up to the 12V center pin on your 6-Pole connector. Typically, a 12V outlet like # RM-9332 is wired to the vehicle battery through a fuse box, as shown in the included installation video at the bottom of the page. This allows the Blue Ox Patriot II # BRK2016 to be powered by your vehicle's battery,...
    view full answer...
  • Does the Roadmaster Battery Charge Line Kit for Towed Vehicles Need Grounded
    The Roadmaster Battery Charge Line Kit for Towed Vehicles part # RM-156-25 does not require any additional ground. In regards to the trailer connector on the tow vehicle or toad vehicle these will both be grounded as will the batteries that the charge line connects to. In order to bridge the charge line from the motorhome to the toad, the Roadmaster Diode 7-Wire to 6-Wire Flexo-Coil Wiring Kit part # RM-15267 is my recommendation since there is an extra pin present to use for the charge line.
    view full answer...
  • Troubleshooting Charge Line Kit Not Working When Flat Towing a 2017 Subaru Crosstrek
    What you are describing sounds like the 15A circuit breaker that comes with the Charge Line Kit # RM-156-25 is shot. This can easily be replaced with another circuit breaker like the 20A # 9506P but since your kit is only a year old it would be good to check your wiring as well as these shouldn't go out that quick. Check to make sure that all of the wiring looks good and it isn't exposed. If you do see that some of the wiring is damaged or exposed and you need replacement wire then we...
    view full answer...
  • Is a Charge Line Kit Needed on a 2014 Honda CR-V if the ACC Fuse is Pulled for Flat Towing
    Unless you are using a supplemental braking system like the Blue Ox Patriot II # BRK2016 which draws power from a 12V outlet like part # RM-9332 then you would need the Charge Line Kit # RM-156-25 when the ACC fuse is pulled on your 2014 Honda CR-V. If you were to install the charge line kit you wouldn't need to pull the ACC fuse or it would act as a safeguard in case you did forget to pull that fuse. For a complete flat towing setup you will need a base plate kit, tow bar, safety...
    view full answer...
  • Installing Roadmaster Battery Charge Line Kit on 2018 Jeep Cherokee
    It sounds like you are referring to the Roadmaster Battery Charge Line Kit # RM-156-25 for your 2018 Jeep Cherokee. This kit allows you to connect your Jeep's battery to the 6-Way or 7-Way plug at the front of the vehicle so that up to 15 amps from the RV's battery can be used to maintain its charge while being towed. If no charge line is present in your RV, you will also need to add the Motor Home Charge Line Kit # RM-156-75. For the charge line kit, you will attach the included length...
    view full answer...
  • Does the Circuit Breaker In the Roadmaster Battery Charge Line Kit Need Grounded
    In regards to the Roadmaster Battery Charge Line Kit for Towed Vehicles part # RM-156-25, the included circuit breaker does not need to be mounted to a metal surface. The installation instructions are as follows, "Find a suitable mounting location for the included circuit breaker; it must be mounted on a flat surface, within approximately 6" of the vehicle’s battery (the closer the better), at a point where it will not interfere with the operation of any components.".
    view full answer...
  • Is a Battery Charge Line Needed When Flat-Towing a 2020 Jeep Grand Cherokee
    The Roadmaster Battery Charge Line Kit for Towed Vehicles part # RM-156-25 can be installed on a 2020 Jeep Grand Cherokee. If you will be pulling power from the vehicle's battery while in tow then it would be a good idea to use the charge line to ensure you don't have a dead battery when you arrive at your destination and are ready to unhook the vehicle from the motorhome.
    view full answer...
  • Can Battery Charge Line Kit be Used With 2020 Chevy Equinox Premier
    The Roadmaster Battery Charge Line Kit for Towed Vehicles # RM-156-25 will not hurt the battery of your 2020 Chevy Equinox Premier; it is compatible with your AGM battery. Also, please keep in mind you will also need the Roadmaster Battery Charge Line Kit for Motorhomes # RM-156-75 if your motorhome does not already have a working 7-way. I have added a link to installs for you to take a look at as well. The rest of the parts needed to flat tow your '20 Equinox are as follows: - Base...
    view full answer...
  • Will Roadmaster Battery Charge Line Kit Overcharge Battery
    The Roadmaster Battery Charge Line Kit # RM-156-25 provides up to 15 amps of power which is perfect for maintaining the battery on your Jeep but it's not enough that you ever need to worry about it being overcharged. The kit does feature a circuit breaker to help isolate the circuit from issues but it won't by itself prevent back-feeding. This isn't typically a concern with this kind of setup but if you wanted extra peace of mind you would just need to add a single diode like # RM-690...
    view full answer...
  • Do I Need A Charge Line From Motorhome To Flat Tow 2019 Chevy Equinox?
    You do not want to pull any fuses in the 2019 Chevy Equinox when you flat tow and you do want to keep the battery connected. In the past there has been issues with extreme wobble when flat towing an Equinox because of pulling the fuse for the body control module. According to the owner's manual of the 2019 Chevy Equinox you will need to keep the battery connected and use a charge line from the motor home. For that I recommend Roadmaster Battery Charge Line part # RM-156-25. If there is...
    view full answer...
  • Installing Battery Charge Wire Kit For Motorhome and Towed Vehicle Connection
    The Roadmaster Battery Charge Line Kit for Towed Vehicles # RM-156-25 should be installed to the center port of the 6-way trailer connection. If you have a different connection, let me know as most charge kits have this 6 wire connector on the towed vehicle and a 7-way on the motorhome. If you don't already have the charge line for your motorhome, then you will want to use the Roadmaster Battery Charge Line Kit for Motor Homes # RM-156-75 which will have you connect the new wire to...
    view full answer...
  • How to Keep Power to Braking System When Pulling Fuse to Flat Tow 2016 Chevy Equinox
    You do not need to pull fuse 32 if you have a 4-cylinder 2016 Chevy Equinox; if so, leave fuse #32 intact and pull the ABS fuse instead (some models may label ABS fuse as #15 or #16). However, you will still lose power so you are going to need to install Roadmaster Battery Charge Line Kit for Towed Vehicles # RM-156-25 and 12 Volt Outlet Kit # RM-9332. I have added a link to a video install of these kits on a '16 Equinox for you to take a look at. Additionally, if you do not have a charge...
    view full answer...
  • Installing Battery Charge Line on Motorhome and Towed Vehicle to Maintain Dinghy Battery
    The Roadmaster Battery Charge Line Kit for Towed Vehicles # RM-156-25 is a great help for your 2012 Honda CR-V especially because your Patriot brake unit will be drawing power. To utilize this you will need power from your motorhome as well using the Roadmaster Battery Charge Line Kit for Motorhomes # RM-156-75. Since you only have a 4-way on your motorhome and vehicle, you will need a different connection. I recommend using the Adapter 4 Pole to 7 Pole Vehicle End Trailer Connector...
    view full answer...
  • Which Direction Should Diode of Roadmaster RM-156-25 Battery Charge Kit Get Wired
    The correct way to wire up the breaker that comes with the Roadmaster charge line kit part # RM-156-25 is to have the copper post ran to the positive post of the battery that is charging the other vehicle and the silver side to the battery that is getting charged
    view full answer...
  • Why Does the Key Need to be Turned to ACC/ACCESSORY When Flat Towing a 2014 Chevy Spark
    The reason that you need to turn the key to ACC/ACCESSORY when flat towing your 2014 Chevrolet Spark is so that the steering wheel will be unlocked. Otherwise the steering wheel will be locked and you will ruin your vehicle. It will cause your battery to slowly drain, but you can install a Roadmaster Battery Charge Line Kit # RM-156-25 on your Spark to help maintain the battery charge level while it is being flat towed. You can run the wire from the charge line kit to the center pin...
    view full answer...
  • Will Flat Towed Vehicle Charge Line Kit Prevent Back-Feed and Overcharging?
    The Roadmaster Battery Charge Line Kit for Towed Vehicles # RM-156-25 has a circuit breaker to help isolate that circuit from issues, but it will not prevent back-feeding. If you want to prevent back-feeding which isn't typically an issue, you can use the Roadmaster Single Park Light Diode # RM-690. Because you are sharing power between two batteries at a low amperage there is very little risk of a surge issue. Another option is to use the Tow Ready Battery Isolation Solenoid # TR118665...
    view full answer...
  • How To Run a Battery Charge Line on 2019 Ford Ranger for Flat-Towing
    In order to charge the battery on a 2019 Ford Ranger while in tow I recommend the Roadmaster Battery Charge Line Kit for Towed Vehicles part # RM-156-25. The connection can then be bridged with the Roadmaster 7-Wire to 6-Wire Flexo-Coil Kit part # RM-146-7. This is by far the best option, all you need to do is install a 6-way on the vehicle which is provided and then you don't have to make any additional connections each time you get setup. I don't have any good options for a dedicated...
    view full answer...
  • Parts Needed to Charge Battery of Towed Vehicle while Flat Towing
    I have exactly what you are looking for, but the ease of install can be a bit of a loaded question. If you are comfortable dealing with trailer wires such as the occasional splicing or battery terminal connection, then this install will be easier than falling asleep in a La-Z-Boy recliner. If you've never touched a trailer wire before, then I've attached a video that will hopefully put your mind at ease that you can do this yourself. This can definitely be a DIY type of installation. To...
    view full answer...
  • Way to Charge Jeep Wrangler Battery While be Flat Towed
    The Blue Ox Patriot part # BRK2016 will draw power from your Jeep battery but there are ways to help keep the battery from draining. The # RM-156-25 is a battery charge line kit that would work well on your Wrangler. I attached an install video for this kit on a similar Wrangler for you to check out as well.
    view full answer...
  • Does the 2020 Ford Escape Hybrid Require the Use of a Charge Line Kit While Being Flat Towed
    According to my source at Roadmaster, the 2020 Ford Escape Hybrid does not require a battery charge line kit like the # RM-156-25 when being flat towed by an RV, and there are no fuses that are required to be removed. Adding a charge line kit would likely cause issues with the battery system on your hybrid vehicle so we do not recommend this application.
    view full answer...
  • Troubleshooting Battery Charge Line Kit on 2018 Jeep Cherokee
    I can assume you are using the recommended Roadmaster Battery Charge Line Kits # RM-156-25 for towed vehicles and # RM-156-75 for motor homes. I've added links to installs of these kits for you to refer to so you can ensure your install followed the same process. If by "switched" or "unswitched" you are asking if the 12 volt circuit turns off when you turn off your RV, then it seems as if it is not switched. You will want to disconnect your 2018 Jeep Cherokee from your RV when you are...
    view full answer...
  • Solution for Preventing Vehicle's Battery From Draining Due to Draw of Blue Ox Patriot Braking
    We have the part # RM-156-25 which allows you to run a charge wire from the vehicle towing your Equinox to keep the battery topped off. This will offset the amperage draw that the Blue Ox patriot puts on the system to operate. I attached an install video for this kit on a similar 2016 Equinox for you to check out as well.
    view full answer...
  • How To Prevent the Battery From Draining While In Tow on a Nissan Frontier
    I spoke to my contact at Roadmaster who is considered by most to be the leader in flat-towing equipment and information. They informed me that you can prevent the battery drain issue you are having by installing a change line on your Nissan Frontier with the Roadmaster Battery Charge Line Kit for Towed Vehicles part # RM-156-25. If your motorhome doesn't have an active 12 volt pin on the 7-way then you will also need the Roadmaster Battery Charge Line Kit for Motorhomes part # RM-156-75....
    view full answer...
  • Which Pins to Use for Charge Wire of # RM-156-25 When Attaching to Trailer Connector
    The center pin of a 6-way is typically the 12 volt accessory circuit which is commonly used for charging batteries. The same 12 volt pin on a 7-way is the one in the 1:00 position. Between the two connectors styles those are the correct pins to use.
    view full answer...
  • Installing Battery Charge Line To Power Tow Vehicle
    The Roadmaster Battery Charge Line Kit for Towed Vehicles # RM-156-25 and the Roadmaster Battery Charge Line Kit for Motor Homes # RM-156-75 will allow you to power your tow vehicle through a 6-way or 7-way wiring connection between vehicles. If you want a separate connector you can run a cord for that, but most people use the 12V pin or another unused pin and the 7 to 6-way cable to power their connection using a cord like the Roadmaster 7-Wire to 6-Wire Straight Cord Kit - 6-1/2' Long...
    view full answer...
  • Battery Charge Kit for Flat Towing Vehicle and Keeping Battery Topped Off
    Roadmaster has the battery charge kit part # RM-156-25 which will help keep your Jeep Cherokee's battery topped off as you flat tow it. Basically this kit provides a circuit from the 12 volt pin of the tow vehicle's wiring and then runs it to the positive post of the battery.
    view full answer...

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