Roadmaster Battery Charge Line Kit for Towed Vehicles
(440 reviews)
Price: $44.66
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Roadmaster Battery Charge Line Kit for Towed Vehicles
Item # RM-156-25
Retail:$48.86
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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
Installation Details
Video of Roadmaster Battery Charge Line Kit for Towed Vehicles
Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.
Video Transcript for Roadmaster Battery Charge Line Kit Review
Ryan: Hey everybody, Ryan here at etrailer. Today, we're going to be taking a look at the Roadmaster battery charge line kit for towed vehicles. The charge line's going to be a really simple kit. It's just going to consist of a little bit of wiring and the breaker that we have mounted right here out of the way. On the purpose of the charge line kit is to more or less trickle charge or maintain your battery whenever you're flat towing it down the road. And that's important because your braking system is going to use your battery power to operate whenever you are towing it.
And the last thing you want is to get to your destination and unhook and go to start up your truck and the battery be dead. But the charge line, you're not going to have to worry about that. It's going to maintain that battery life, that way you're not going to have to deal with trying to get some jumper cables from your motor home to here, deal with grabbing a jump box or even bothering someone else to help you out.We do get some questions asking about if the charge line kit is going to affect your motor home's battery, which is definitely understandable, but the answer is no. Since the charge line is going to get the power from the auxiliary power source at the seven-way plug, you're not going to have to worry about it stealing or robbing your motor home's battery power. So the way it's going to get that power, the current is going to run through your cable from the back of your motor home into your plug and the charge line wire is going to be connected to the back of the plug.
From there, your wires is going to run up to one side of the breaker and the breakers there to prevent the current or electricity from backfeeding so that'll kind of put your mind at ease, knowing you're not going to have to worry about that power backfeeding. With that being said it'll cross the breaker, come through this wire, and this is going to run and get connected to the positive terminal on your Ranger's battery.So overall really simple component, that's going to keep our battery charged and one less thing we're going to have to worry about, and that can really make a big difference whenever you're on vacation, going from relaxing to stressful if your battery does die. A charge line kit is going to prevent that. And that'll finish up our look at the Roadmaster battery charge line kit for towed vehicles.
Customer Satisfaction Score:
96% were satisfied with this product
4% of customers were not satisfied
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Customer Reviews
Roadmaster Battery Charge Line Kit for Towed Vehicles - RM-156-25
Average Customer Rating: 4.8 out of 5 stars (440 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.by: Jeffrey12/22/2021
have successfully completed the installation of the following items that I purchased from etrailer:
> Nighthawk RM-676 tow bar
> RM-524458-5 base plate
> DEMCO Stay in play DM86VR
> RM-152 diode wiring kit
> RM-156-25 charge wire kit
> RM-88400 brake switch relay kit
I work slow but methodically. I had no issues other than the high degree of difficulty for a 68 y/o man working alone. This project exceeds the abilities of someone NOT mechanically inclined. There is also the need for some specialty tools. I found that feeding the wiring through the dash, firewall, and underbody was more difficult than installing the front baseplate. Overall, I am satisfied with the function of this installation. I am glad I did it myself rather than having it done.
Tow vehicle: 2021 Entegra Emblem 36U
Towed vehicle: 2018 Ford Fusion Platinum Energi
Comments
I have no regrets with this purchase. Items preform as advertised with no issues. I am very satisfied with Roadmaster and Demco products.
Jeffrey - 11/19/2022by: Lon08/05/2022
Forgot this when I ordered my tow bar and parts. Arrived in just a few days. Easy install.
Suggestion for Roadmaster - need to provide terminal covers. Made my own using some vacuum hose caps and rubber tubing.
by: Travis04/04/2022
This is an easy install with simple instructions. Verify connection to vehicle 6-pin trailer power connector and correct stud (gold) on circuit breaker block; other stud (silver) goes to BATTERY.
by: Dunia09/12/2022
Excellent service. However, We been waiting for this part. First the Post office said that it would deliver on Sept 9, then Sept 10 and it was here Sept 12. We had to postpone our trip because of the delivery date. Do not sent mail trough the USPO they do not deliver on Saturday or Sunday.
by: John 11/24/2022
product works great! Customer service was outstanding, new exactly what I needed for my RV/towing needs and easy to work with !
by: Doug06/17/2022
My experience with etrailer was good from the perspective of the cooperation and pleasantness. However, even though I was clear on the tow bar I had (Blue Ox) and the vehicle I was towing (2005 Dodge Dakota) when the tow package came and the shop I had installing it got to the end of the installation, it was discovered that the wrong pins were sent, i.e. they wouldn't lock in place - too short . At first we couldn't determine what the problem was, so I called etrailer back. Was told those were the correct pins. Finally called Blue Ox directly and the rep immediately told me (after I gave him the PN) that those were the wrong pins. Without me asking he offered and did send two replacement pins free of charge. They worked perfectly.
by: Kirk05/27/2022
It was a good experience. The only negative is not being able to see trailers in person, but I knew that going in, so that’s my decision. Overall the value was excellent, and I was able to get the trailer i wanted at a great price with plenty of custom upgrades at a far better price than anyone local, which is why I chose to buy a trailer from Half way across the country. I would certainly do it again.
by: Roy07/24/2017
I ordered all the parts required to safely flat tow out 2017 Jeep Cherokee Trailhawk from etrailer.com. The only part they didn't have was the Mopar Flat Tow Enhancement kit Jeep requires to flat tow this model.
Ordering from them was great, the website is easy to use and I was able to locate all the pieces compatible with my specific vehicle. The expert recommendations help my decision choosing the right parts. I ordered from etrailer even though I found some of the parts on other websites a little cheaper. I chose to pay a little more because of all the effort etrailer has put into installation videos and guides. I was very pleasantly surprised to learn from etrailer that they have a price match guarantee!
So my equipment consisted of the following
Mopar Flat Tow Enhancement Kit (from Jeep)
Roadmaster Battery Charge Line Kit for Towed Vehicles
Mighty Cord 7-Way RV Style Trailer Connector - Trailer End
WesBarg 7-Way, RV-Style Connector w/ 6' Long Coiled Cable Trailer End
Pollak Black Plastic, 7-Pole, RV Blade-Style Trailer Socket - Vehicle End
Hopkins Custom Tail Light Wiring Kit for Towed Vehicles
SMI Stay-IN-Play DUO Supplemental Braking System
Roadmaster Brake-Lite Relay Kit for Towed Vehicles
Blue Ox Alpha Tow Bar - Motor Home Mount - 6,500 lbs
Blue Ox Base Plate Kit - Removable Arms
Blue Ox Tow Bar Cover - Aladdin, Aventa LX, Aventa II
The installation videos are great but not all inclusive. Take the time to read the instructions that come with the parts. This is a major project, I took about 30 hrs over a full week but as you'll see in the pictures I took s few extra steps to make a cleaner look.
Some of those extra steps:
The base plate install requires the bumper be modified cutting off a flange on each side, I spray painted this to prevent corrosion.
In the install video of the baseplate on the drivers side they use an extra quick link (not included) to run the safety cable around the wiper fluid reservoir. I took the time to remove it and run the safety cable behind it.
I didn't want our nice new vehicle to look like it can be towed so I played the brake away switch and 7 way trailer plug behind the license plate, so when not being towed our vehicle looks great!
Some things to be aware of. The Brake air cylinder that mounts to the brake pedal with four bolts may need longer bolts, it did on our Jeep. Spend the money for weather tight heat shrink crimp fittings. The Hopkins wire harness was about 1.5 feet short to get to my plug location. Buy extra zip ties, electrical tape and split loom.
I recommend reading all the various installation manuals and watching all the videos because the various components integrate together and if you install one at a time you'll be doing a bunch of extra work.
The brake light relay is a real pain in the butt, not because of the hardware but because of the location of the brake light switch which is very hard to get to.
Overall I am very happy with the products and how the installation looks. We haven't towed it yet but do not expect any problems.
Comments
Still very happy with our purchase. We’ve towed over 10k miles and have had zero issues with our tow setup. I’ve shared my experience with several other RVrs and recommended your company for their needs. Thank you,
Roy - 07/30/2018by: Garry11/23/2022
Installation instructions were great
by: Terry 11/04/2022
I called in and explained my problem and Victoria was quick to understand what was happening ( or not happening) and explained the productI would eliminate my problem. I received the kit in three days and installed it and I will be towing without having to worry about starting my vehicle at the end of a long day of towing .
by: Robert 09/13/2022
Item arrived promptly. Quality was very good, and the installation instructions were easy to follow. Price was also very reasonable compared to other similar offerings.
by: Steve03/25/2022
These were exactly what I needed. I changed tow vehicles to a Honda HRV (manual) and the only base plate available was the Roadmaster. These adapters took about 10 minutes to change my Blue Ox tow bar to accept the Roadmaster.
by: Leonard04/09/2022
Ordered and install base plate over a year ago and finally got to use it a couple of weeks ago because motorhome was in shop waiting on parts. Pandemic and supply chain issues. Anyway, the base plate and accessories work great. Dinghy tracks well. Hardly know it’s back there.
by: Patrick05/02/2022
Over the past few years, I've ordered several items from etrailer. The purchasing process was very easy and timely. They're instructions and videos for installation are spot on! I will continue to buy from etrailer for my motorhome and towing needs
by: Jud09/26/2022
It works and was not too difficult to install in my 2008 Jeep Wrangler.
by: William 09/15/2022
Does good job keeping car battery charged when towing.
by: Kim 08/12/2022
I’ve ordered several parts from etrailer all have been good quality and showed up quickly. The advice from the consultant are spot on. There videos for installation are very helpful also.
by: Gary06/06/2022
This is really a must for most toads if you have to have the key in the ignition and/or have a braking system. Easy to install.
by: Roland11/20/2022
Yes I use it from my motorhome to the jeep I tow and to the trailers.
by: Gary 07/09/2022
All of the parts ordered fit perfectly and the tow hitch works great.
by: Charles06/30/2022
I received the charge line on time and easy directions enabled me to do a self install!
by: Greg 04/24/2021
Installed as per installation video and all went great.
Comments
towed over 7000km last year and worked great. no dead battery
Greg - 04/25/2022by: Hal03/21/2022
was not needed (returned) because the Delta Force supplemental brake kit already provided
by: Herbert03/15/2022
Easy install for anyone with good mechanical ability. Towed my Suburban 11,000 miles so far with no issues from the base plate.
by: Douglas11/27/2022
Quick shipping. Haven't installed yet, but everything I need.
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See what our Experts say about this Roadmaster Accessories and Parts
- Can Vehicle be Started with Battery Charge Kit # RM-156-25 InstalledIf you had the Roadmaster Battery Charge Line Kit # RM-156-25 installed it would not be an issue for you to start your Equinox. It wouldn't hurt either vehicle.
view full answer... - Recommended Way to Charge Vehicle Battery that is Being Flat TowedBest option we have for charging a vehicle battery while being flat towed is the is the Roadmaster Battery Charge Line part # RM-156-25 which is specifically designed for this. Otherwise you can use a 6 or 7-way connector and wiring to give you the ability to run extra circuits. Easiest way to do that though is based on what type of connector your RV has at the rear. With that info I can come up with the best solution.
view full answer... - Does Installing Roadmaster Battery Charge Line Kit # RM-156-25 Require Additional GroundingWhen installing the Roadmaster Battery Charge Line Kit # RM-156-25 you do not need to ground anything. The power from the tow vehicle's battery will easily transfer to the towed vehicle's battery and not need any additional grounding.
view full answer... - Which Pins to Use for Charge Wire of # RM-156-25 When Attaching to Trailer ConnectorThe 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... - Recommended Charge Line For Jeep Battery Using Brake Buddy Supplemental Braking System to Flat TowFor your Brake Buddy, the power should come from your vehicle battery to prevent a loss of power to your braking system. However, if you utilize the 12V power at your 7-way and use the Roadmaster Battery Charge Line Kit for Towed Vehicles # RM-156-25 you will prevent any issue with your vehicle battery. The charge line will send a maintenance charge to your Jeep Battery while you are towing (averaging 2-4 amps at 12V because it is what is generated by your alternator beyond the power...
view full answer... - Solution to Allow Battery of 2010 Kia Soul to Stay Topped Off When Flat TowedBest option would be to install the Roadmaster Battery Charge Line Kit for Towed Vehicles # RM-156-25 which will keep the battery of your 2010 Kia Soul topped off when it's being flat towed. Basically it wires from the 12 volt pin of your 7-way to the positive battery post of the towed vehicle battery to keep it topped off.
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... - Recommendation for Charging Battery of Vehicle Getting Flat TowedWe have the Roadmaster Battery Charge Line kit part # RM-156-25 which comes with everything you'd need to run a charge wire from your tow vehicle to your Jeep Wrangler getting flat towed.
view full answer... - Solution for Preventing Vehicle's Battery From Draining Due to Draw of Blue Ox Patriot BrakingWe 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... - Which Wire Goes Where on the Roadmaster Battery Charge Line Kit Part # RM-156-25The red wire that connects to the battery on your 2016 Jeep Wrangler Unlimited will need to be attached to the silver terminal labeled as "auxiliary" on the circuit breaker that comes with the Roadmaster Battery Charge Line Kit part # RM-156-25. The red wire that connects to the 6-pin trailer connector on the front of the vehicle which in turn runs to the motorhome's battery will need to be connected to the copper terminal labeled "Bat" on the included circuit breaker. I have attached...
view full answer...
- Battery Charge Kit for Flat Towing Vehicle and Keeping Battery Topped OffRoadmaster 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... - Charger Recommendation for Vehicle Getting Flat TowedWe have the Roadmaster Battery Charge Line kit part # RM-156-25 which comes with everything you'd need to run a charge wire from your tow vehicle to your vehicle getting flat towed.
view full answer... - Which Direction Should Diode of Roadmaster RM-156-25 Battery Charge Kit Get WiredThe 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... - Can the Battery Charge Kit # RM-156-25 be Installed without the Included Circuit BreakerIt would not be good to install the Charge Line Kit # RM-156-25 without the included circuit breaker. The circuit breaker is what would cut the current if something were to happen.
view full answer... - Recommended Battery Charge Line Kit for Vehicle Being Flat Towed to Keep Battery from DrainingIt doesn't matter what order you disconnect the battery and turn the key because the battery will still be disconnected from all those functions if you were to remove that positive terminal. Without knowing exactly what parts you have connected, disconnecting that battery could cause you to lose vital features like supplemental braking. I don't recommend disconnecting the battery on your vehicle and instead recommend you simply add the Roadmaster Battery Charge Line Kit for Towed Vehicles...
view full answer... - What Gauge Wire Is In Roadmaster Battery Charge Line Kit for Towed VehiclesYes, 14 gauge is correct. The Roadmaster Battery Charge Line Kit for Towed Vehicles part # RM-156-25 comes with 14 gauge wire.
view full answer... - Does the Circuit Breaker In the Roadmaster Battery Charge Line Kit Need GroundedIn 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... - Will Roadmaster RM-156-25 Battery Charge Line Kit Overcharge Batter in Towed VehicleBecause the circuit provided by the # RM-156-25 Battery Charge Line kit only provides 15 amps, enough to do the job but not so much that there's any danger of overcharging the battery. I've linked to an installation video that I hope you'll find helfpul.
view full answer... - Is Charge Line Needed For 2015 Chevy Equinox When Using Ready Brute Elite Tow Bar Braking SystemSince the Ready Brake system on your Ready Brute Elite Tow Bar just uses weight/momentum to pull the brake pedal in the vehicle down when stopping (and not any power from the battery) it is not necessary to add a charge line kit. You certainly still could just for peace of mind, in which case the Roadmaster # RM-156-25 would work perfectly, but it's definitely not required. Just keep in mind that you will still want to pull the appropriate fuses as listed in the owner's manual for your...
view full answer... - Recommendation to Keep Towed Vehicles Battery Topped OffWhat a lot of people do to keep the battery topped off is very similar to what you described ha "hillbilly" haha. It works though so in the end that's what really matters. We have a kit part # RM-156-25 which comes with wire, a circuit breaker, and some ring terminals to give you all that'd you need. I attached an install video for this kit on a similar passenger vehicle as yours for you to check out as well.
view full answer... - Flat Towing a 2010 Hummer H3 Behind Motorhome Battery Drain Issue SolutionIf there is a fuse that should be pulled in your H3 when flat towing it will be mentioned in the owners manual under the section for flat towing procedures. I can't find anything that states that there is though. What we do offer that will help is a battery charge kit for vehicles that are being flat towed like the Roadmaster charge kit part # RM-156-25. This will put a maintenance charge on the vehicle battery as you flat tow it to keep it topped off.
view full answer... - Switch 12V Constant Running to Reverse Light Pin on 7-Way to 12V Pin to Charge Towed Vehicle BatteryThe previous owner of your 2008 Leisure Travel Vans Serenity could have wired the 12V wire to the reverse light pin. As such, a possible solution to your problem could in fact be to relocate that circuit to the 12V pin. From there, you can see if the # RM-156-25 is actually supplying power to your battery. If this doesn't solve your problem or causes any other complications, let me know and I will assist you further.
view full answer... - Is a Battery Charge Line Needed When Flat-Towing a 2020 Jeep Grand CherokeeThe 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... - No 12 Volt Power At 7-Way Trailer Connector On 2015 Ford F-150This is a pretty common function of the smart tow package/feature on these new Ford F-Series Pickups. It's not usually a fault but rather just a misunderstanding of how the system works. The battery charge line circuit won't provide current until the trailers is connector and gear shifting begins. It also must first be turned on via the in-dash settings if not already done so. This feature can be troublesome so if you wish to have constant power to the battery charge line circuit at all...
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