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Roadmaster Automatic Battery Disconnect with Switch for Towed Vehicle w/ Supplemental Braking System

Roadmaster Automatic Battery Disconnect with Switch for Towed Vehicle w/ Supplemental Braking System

Item # RM-766
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Roadmaster Auto Battery Disconnect Accessories and Parts - RM-766
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Conveniently disconnect your battery so that your vehicle can be flat towed per manufacturer instructions. System with switch charges your towed car's battery during towing to prevent dead battery and maintain charge for accessories. Call 800-298-1624 to order Roadmaster accessories and parts part number RM-766 or order online at etrailer.com. Free expert support on all Roadmaster products. Guaranteed Lowest Price and Fastest Shipping for Roadmaster Automatic Battery Disconnect with Switch for Towed Vehicle w/ Supplemental Braking System. Accessories and Parts reviews from real customers.
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  • Reviews (97)
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Roadmaster Accessories and Parts - RM-766

  • Tow Bar Wiring
  • Auto Battery Disconnect
  • Roadmaster

Conveniently disconnect your battery so that your vehicle can be flat towed per manufacturer instructions. System with switch charges your towed car's battery during towing to prevent dead battery and maintain charge for accessories.


Features:

  • Lets you easily disconnect your battery so that your vehicle can be towed behind your RV
    • Can only be used on vehicle on which battery must be disconnected for towing
    • Includes switch for installing in the towed vehicle
    • Consult your owner's manual
  • Eliminates inconvenience and the potential danger of pulling your battery cable
  • Operates with switch
  • Includes a corrosion-resistant, marine-grade solenoid with 200-amp constant duty and 600-amp surge
  • Works with almost any 12V battery
  • Comes pre-assembled for easy installation


Notes:

  • Disconnecting the battery, whether manually or with the Roadmaster automatic disconnect, will affect your vehicle's electronics. You will need to reset various electrical components in your vehicle following use of this product.
  • Not for use with diesel engine vehicles, due to the high compression ratio of diesels the engine can surge up to 10 times that of a gasoline engine at start up and can cause the solenoid to fail.
  • A charge line, (RM-156-25 - sold separately), is a good idea if you have a braking system that is using power from the towed vehicles battery while it is disconnected.


766 Road Master Automatic Battery Disconnect

Replaces 765

Installation Details RM-766 Installation instructions

This Product Fits The Following Vehicles





Customer Reviews

Roadmaster Automatic Battery Disconnect with Switch for Towed Vehicle w/ Supplemental Braking System - RM-766

Average Customer Rating:  4.9 out of 5 stars   (97 Customer Reviews)

Conveniently disconnect your battery so that your vehicle can be flat towed per manufacturer instructions. System with switch charges your towed car's battery during towing to prevent dead battery and maintain charge for accessories.

- RM-766
by:

The battery disconnect installation instructions were clear and the installation went well in my 2018 Chevrolet Colorado ... in spite of the kit missing a few pieces like a second star washer for connecting the two battery cables and the second piece of protective tubing. I covered the exposed energized solenoid terminals with electrical tape to prevent an potential inadvertent short in the future when working under the hood. Works as designed so far.


Comments
I towed the Colorado from Maine to Arizona last winter and the battery disconnect worked well for the entire trip. It made preparing the truck for towing and driving very easy!
Mike - 07/01/2020


- RM-766
by:

I received the Roadmaster remote battery disconnect in a timely manner and had it installed in my 2016 Chevy Colorado by a local RV dealer. I used it for the first time this week and it worked like a charm. I didn't lose any of my preset radio stations or any other data that I know of. Pushing a button on the dash is a lot easier than disconnecting and reconnecting battery cables.


Comments
Still working just fine.
Robert M - 09/09/2017



- RM-766
by:

The RM-766 is a solid piece of hardware and comes with absolutely everything required for the install, right down to the "Tow" and "Drive" stickers for the switch. I use it to disconnect the battery in my 2016 Ford Edge 3.5L AWD, to help make it flat towable behind my RV. It works great and I do not have to open the hood and mess with battery cables while travelling. I like it.


Comments
There have been absolutely zero problems with this switch so far. Works like a charm.
Herbert M - 07/13/2018



- RM-766
by:

i've been towing my gmc canyon for the past year .we have gone to ky., mn.,fl.,and mo. with no problems. the towing package i bought was and easy install and took just a few hours by following the instructions. it was money well spent.


Comments
great!
lupe v - 04/04/2021


- RM-766
by:

I gave each and every one of the items I purchased a 5star rating because they each have contributed greatly to my confidence and sense of security about full-time RVing in my Class C rv towing my little car behind. Each product has been well made and thought out and the service from etrailer has been great....from price to shipping and packaging. I couldn't be more pleased with everything. Job well done. Thank you.



- RM-766
by:

I have a 2014 Silverado that I wanted to tow with my RV. In order to tow GM calls for the battery to be disconnected. This was the only product that I fond that would do what I wanted. It is slightly over priced in my opinion but it does the job. I have attached it to my aftermarket air box and ran the switch under the hood release. This way I can use the remote to unlock the doors when I am ready to unhook.



- RM-766
by:

This thing works PERFECT. thanks for the fast shipping as well A+ job guys!


Comments
Still working like a dream, zero problems one year later, thats for a great product
Rick V - 06/16/2021


- RM-766
by:

Have not had any problems with this device , I done research prior to buying it .



- RM-766
by:

Wow!!! So very impressed with this company!!’ Haley helped me by phone make sure everything I ordered was right for my RV and Smartcar (tow bar, base plate, battery shutoff and wiring). It came quick and the quality of the products (Blue Ox) are outstanding. Highly recommend this company!! Thank you for helping me!!



- RM-766
by:

Easy installation



- RM-766
by:

Works exactly as advertised. Much easier than having to physically disconnect the battery every time.



- RM-766
by:

I bought this product because to tow my GMC Canyon I have to disconnect the battery and I didn't want to have to get under the hood every time I hooked up and unhooked the vehicle. This product was easy to install, especially with the on-line video. The only mishap I had was the video said to use a 1/4" drill bit to drill pilot holes for the two sheet metal screws that mount the solenoid onto the inside fender. This makes the holes the same diameter as the screw threads and they won't bite. I had to re-drill new holes with a slightly smaller drill bit. The kit did include two 1/4" nuts and bolts to use instead if you access with your fingers to the backside for placement of the nut. I could use the forward hole for the nut/bolt but the rear hole I had to use the sheetmetal screw as it is a double panel. I wasn't comfortable with the two positive terminals on the solenoid being in a location, where when working in the engine compartment, tools can accidentally touch the positive terminal and the solenoid housing and create a spark. I fashioned a piece of inner tube cut in a rectangle and mounting it above the solenoid onto the sidewall, cut a hole for the top plastic cone to stick thru and it now lays over the solenoid covering the terminals enough where accidental contact is minimized.



- RM-766
by:

This product is much improved over the video that I watched prior to ordering the product. It does not require 3 wires, but 2 wires. The wires are already connected to the solenoid so there is no need to strip wires and clamp on connectors. The switch is a simple push on-off so no stickers are needed to be placed inside the car. Overall it was very simple to install and works great. Only draw back was getting the 2 wires through the firewall. The video showing how to accomplish that task could have been significantly better. 5 second mention of rubber grommet was not enough to help accomplish this task. Bottomline. GREAT product.



- RM-766
by:

The tow bar wiring kit fits well on my Jeep Wrangler and was easy to install. Always great dealing with etrailer, their customer service is excellent. They give great suggestions and guidance on the right products for your needs. They are a fantastic resource...saving you both time and money.



- RM-766
by:

Great company. Always responsive to the customer's needs. Had a needed part sent overnight. Arrived ib 16vhours after order was placed. Allowed for us to begin our journey as fulltime RVers as scheduled.



- RM-766
by:

The instructions were good and they were detailed. The product works as advertised. The button is made so it would be difficult for it to be pushed accidently in most places where it might be installed. The greatest difficulty for me was getting nuts on the mounting bolts for the solenoid. Also, my 2014 Jeep Wrangler had three wires attached to the positive battery post so it was not that straight forward attaching all three to the battery cable. A larger diameter piece of shrink wrap would have helped in this case.



- RM-766
by:

Sold and installed by etrailer. This battery cutout was necessary to tow our Jeep. It works as advertised and the installation work done by etrailer is neat and tidy. Top marks!



- RM-766
by:

As always, etrailer can be depended upon to process, and ship the order right away. I need to disconnect the battery from my Chevy Colorado to flat tow it. The Road Master RM-766 seemed like the most convenient way to disconnect the battery. The unit is easy to install. The instructions are very generic, however in my case there was a video specific to this vehicle that provided a great resource for mounting and hookup. The only thing I am concerned about is the disconnect switch itself - I think it should be more of a "deeper" switch where more movement is required to make contact - a little concerned that it could be inadvertently activated.



- RM-766
by:

I have installed this battery disconnect on a 2017 Ford Focus, 2016 Ford Fiesta and an going to install in a 2014 Jeep Cherokee Trailhawk. I was having some electrical issues before I installed... but good to go now... no issues to report. Customer service was very knowledgeable and helpful



- RM-766
by:

Easy to install. My wife gets our tow vehicle ready to roll. She would not disconnect the battery cable. Now all it takes is a flip of the switch! Happy with this battery disconnect product.


Comments
Our battery disconnect works perfectly every time. Makes preparation for towing much easier
Mike H - 08/24/2018



- RM-766
by:

The items I ordered which are to complete the setup for my Jeep Toad arrived in a timely manner and were exactly what I needed. I have not had the opportunity to install yet but I don’t anticipate any issues as I have reviewed the instructions. Tammie was great to deal with and was very knowledgeable. This is not my first dealings with etrailer and won’t be the last. Great service and knowledgeable. Thanks. Keller Texas. Don’t have any pics yet.



- RM-766
by:

Excellent product and fairly simple to install, works great!



- RM-766
by:

As always eTrailer has good videos to use for assistance an pointers during install. Having a remote disconnect inside the truck during hookup makes all the difference in the world, no more popping the hood to disconnect and reconnect the battery. I installed the switch in the drivers side of the cubby in front of the gear shift knob, this makes it visible only from the passenger seat. So I see it as a theft deterrent as well, because from the drivers seat you don't even know it is there.



- RM-766
by:

Great product.. a must if you flat tow a vehicle like my GMC Sierra truck that requires you to disconnect the battery when you tow it. Push a button and the battery is disconnected, push it again and its reconnected.. it's that simple to disconnect the battery.



- RM-766
by:

Works great


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Ask the Experts about this Roadmaster Accessories and Parts

  • How Does Supplemental Braking Kit Get Power on Vehicle that Battery Gets Disconnected
    We have just what you need. For vehicles that have to have the battery disconnected to be flat towed but then use a supplemental braking system designed to draw power from the towed vehicle you'd want the outlet kit part # RM-9332. This actually wires directly to the vehicle battery so when the vehicle is disconnected it still gets power.
    view full answer...
  • Will Battery Disconnect Unlock Steering Wheel When Flat Towing 2020 Chevy Silverado 1500
    According to the owner's manual of your 2020 Chevy Silverado 1500, Step 11 of the instructions to dinghy tow, it says: "If the vehicle has an ignition key, keep it in the towed vehicle in ACC/ACCESSORY to prevent the steering column from locking. If the vehicle is equipped with Keyless Access, keep the RKE transmitter outside of the vehicle and manually lock the doors. Access the vehicle by using the key in the door lock." I also recommend checking out the owners manual and referring to...
    view full answer...
  • Flat towing a 2021 Tundra behind a Motorhome
    Yes, to keep your steering wheel unlocked you will want to hook up a Remote Battery Disconnect # RM-766. You will than simply turn on your ignition without pushing your brake pedal. When the steering is unlocked you will than push the disconnect button that will turn off all the power to your 2021 Toyota Tundra. If you are already using a Blue Ox towing system you will need the Base Plate # BX3794. Be sure that your tow bars are rated for the weight of your truck. The Blue Ox Ascent...
    view full answer...
  • Why Does Battery of 2014 Ford Fiesta with Automatic Transmission Have to be Disconnected
    The automatic transmission of your 2014 Ford Fiesta shifts electronically which is why the battery has to be disconnected when flat towing as well as following all of the other procedures outlined in the manual. You will have transmission problems if you don't disconnect the battery. I found a few people online who flat towed without disconnecting the battery and they had to have the transmission rebuilt. The transmission basically dropped back into gear while they were flat towing which...
    view full answer...
  • Will Roadmaster Automatic Battery Disconnect Work on 2021 GMC Sierra 1500 AT4
    I checked with Roadmaster to verify, and your 2021 GMC Sierra 1500 AT4 is compatible and will work with the Roadmaster Automatic Battery Disconnect with Switch # RM-766. The only caveat is if you have a diesel engine as the battery disconnect is not compatible with a diesel engine on any vehicle. In regards to the positive terminal being disconnected, I could find no mention of that anywhere. I took a look at the latest owner's manual available for the '21 Sierra and it only states,...
    view full answer...
  • Why Does Battery of 2018 Ford Focus Have to Disconnect to Flat Tow It
    In order to unlock the steering wheel of your 2018 Ford Focus the key needs to be in the on position. The problem with this is that it will drain the battery if left like that. So you have to disconnect the battery so that it doesn't drain and the steering wheel remains unlocked. The Roadmaster Automatic Battery Disconnect # RM-766 that you referenced is a great solution for this as it automatically disconnects the battery and with the charge line kit part # RM-156-25 it can also put...
    view full answer...
  • Does Roadmaster Battery Disconnect Work with Diesel 2020 Chevy Silverado 1500 3.0 Liter
    I checked with Roadmaster and the RM-766 cannot be used with the diesel engines likes what you have in your Silverado. The lighting kit part # RM-152-98146-7 will fit and work great in your 2020 Chevy Silverado 1500.
    view full answer...
  • Do I Need Battery Disconnect Switch To Flat Tow 2016 Ford Edge and Why
    According to the owner's manual for the 2016 Ford Edge it is required to disconnect the negative cable from the battery to flat tow the Edge behind a motor home to prevent draining the battery. Most of the time when the manufacturer calls for the battery to be disconnected before flat towing there is a vehicle feature that will draw power from the battery while it's not being started frequently. We strongly recommend the use of the Roadmaster Automatic Battery Disconnect part # RM-766...
    view full answer...
  • Recommended Battery Disconnect System for Flat Towing GMC Canyon Diesel
    You are right that the Roadmaster Automatic Battery Disconnect # RM-766 cannot be used with diesel engine vehicles like your GMC Canyon. The issue is the high compression ratio of diesels that cause the engine to surge up to 10 times that of gas engines, which can lead to failure on the solenoid. What you can use instead is an alternate-style battery disconnect like the Deka # DW05312 or the Epicord # 277-000096 that includes a switch you could mount inside the cab. This still allows...
    view full answer...
  • Battery Disconnect Needed When Flat Towing a 2017 GMC Sierra 1500
    The battery disconnect that you should use when flat towing your 2017 GMC Sierra 1500 is the Roadmaster # RM-766. If you don't already have a wiring kit installed on your pickup then I also recommend installing the Flexo-Coil Wiring Kit # RM-15267 and the connecting the charge line kit # RM-156-25 from the center pin of the 6-Way connector to your battery so that your battery won't drain while flat towing. I have attached some sample installation videos for you to reference. For...
    view full answer...
  • Battery Disconnect for Flat Towing 2016 Ford Focus
    The battery terminal on your 2016 Ford Focus does need to be disconnected, but you are absolutely right that you can use the battery disconnect. The right one for your 2016 Focus is the Roadmaster Automatic Battery Disconnect with Switch # RM-766. I have added a link to the instructions as well as a link to a video of the disconnect being installed on a Focus for you to check out.
    view full answer...

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