bing tracking image

Roadmaster Automatic Battery Disconnect Review

content loading

Customers compare RM-766 to these similar products




Products Featured in this Video



Review of the Roadmaster Automatic Battery Disconnect


Brent: Today we'll be having a look at the Roadmaster Automatic Battery Disconnect with Switch for Towed Vehicles with a Supplemental Braking System, part number RM-766.Now the reason you're going to want this battery disconnect over other options on the market is because it's so simple to operate. Just a simple push of the button, you can reconnect your battery or disconnect your battery. You don't have to go underneath the hood, use any tools to disconnect your battery, or open the hood to operate a switch. This is all done from inside the cab of your vehicle, which makes it a very simple process.As you can see here, our battery is connected because our dome light's on in the vehicle. When I press the button, we'll hear the click and then we lose power. You can tell by the dome light going off.

When I press the button again to reconnect our battery, after a few seconds, once the computer system in the car reboots itself, you'll see our dome light kick back on.Here's what it looks like underneath the hood. We have our solenoid here with our two battery cables. One connects directly to the vehicle's existing battery cable and the other one will connect to the main fuse box. This goes in-between it to kill power to the vehicle.Now we have two wires that'll go inside the firewall through this gray duplex wiring, and those will connect with our switch. Those are the only connections we have inside the vehicle.

There's a white wire that comes off of here, which we need to attach to a ground. I have our white wire attached to the negative terminal on our battery, which goes directly to a ground point.Great thing about this battery disconnect kit is that we have a variety of options in order to mount our solenoid. In our particular application here, I used the provided self-tapping screws to secure it directly to the sheet metal of the vehicle. We also have nuts and bolts that are included, so if you wanted to attach it to a piece of plastic, or another option, you can secure it with the nuts and bolts if needed.This battery disconnect kit is a great option for vehicles that require the battery to be disconnected when the vehicle is being flat towed behind a motor home. It works great for all vehicles that have a 12 volt battery system that only have a single battery so this is a great option for most gasoline-powered vehicles.

If you have a diesel-powered vehicle, in most instances, you have dual batteries and this kit won't work for that.Now, on the trigger wire circuit that initializes the solenoid to open or close, we have a 7.5 amp fuse and a provided fuse holder to help protect the circuit.That completes our look at the Roadmaster Automatic Battery Disconnect with Switch for Towed Vehicles with a Supplemental Braking System, part number RM-766. Speaker 2: All right guys, what do we think about the Roadmaster Battery Disconnect Brent: I really liked it because it's a simple solution. You don't need to use any tools. You don't have to go underneath the hood at all. You're already inside the vehicle.

All you do is press a button and you're done. Speaker 2: Ease of use is definitely a benefit of this. Speaker 3: Yeah. Compared to the other options out there, open the hood, actually unscrew a bolt and make sure that you get the battery cable off of the battery terminal or away from the aftermarket. Just regular old cheap disconnect. Then, make sure that can't interfere with that positive battery post and cause sparking and everything while you're driving, towing a car behind you. This is a solid and you know it's done solution without any worries while you're going down the road. Brent: Also, some of the cheaper disconnects that have the little red keys. You have to worry about losing the key. There's nothing to worry about losing here. You install it once and you're done for life. Speaker 2: Speaking of installation, I mean, it didn't look very hard. Brent: No. Actually it's probably one of the easier things to install if you're doing a flat tow setup behind your motor home. It's basically you have the two main connections for the battery and the fuse box for the battery cable, however you have your particular care set up. You have to pass two wires through the firewall, hook it up to the switch and then the one for the ground wire and that's it. Speaker 2: They include the wire and everything in the kit. Speaker 3: Yeah. Everything. Brent: Yep. Speaker 2: All right. Brent: Everything that you see there will work for most applications. I mean, for some cars you may need to extend the length of the cables a little bit just depending, but for most applications this will work just fine as is. Speaker 2: The only thing that I would say is a drawback would be that out of the box you can't supply power to your toad's battery. It requires a separate part or a separate cable. Speaker 3: Yeah. If you're wanting to charge the battery because you have a . in the floorboard braking system like an even brake where it's got a little compressor in it and it is running off the car's battery you would have to run the wire from the battery side of the battery disconnect down to your six pole round or four pole round on the front of the car to provide a maintenance charge for the battery from the motor home. That's another kit that's absolutely available and I think it's RM156-25 from Roadmaster. Speaker 2: Even then, it's not like a huge effort to add that. Speaker 3: No. It's pretty straightforward. It's providing power from the power wire and the 7-way motor home to the car's battery, provide a maintenance charge. Speaker 2: Now, there aren't a whole lot of kits like this that we can really compare it to are there Speaker 3: No. The comparison would be to a manual post that sticks together with a bolt or a wing nut or the kind Brent was talking about with the red switch that turns on and off and you can take the key out and then you always got to make sure you have a spare key in case you lose the one you're using. This way you don't have to open the hood every time you hook up the car and get in there and do stuff. It's automatic. Just press the button, shuts the battery down. Brent: Somebody would definitely choose this over other options because of convenience. Once it's installed, it's so much easier to use. There's no maintenance, no keys, no crawling underneath the hood, nothing like that. As far as why they might choose the other options, well, more cost-effective. I mean, this is more of a premium line product, but you're paying for the convenience and the ease of use. Speaker 3: And the quality part too. I mean, when you pick this up you feel that this is probably four pounds. The wire's heavy. The solenoid's heavy. It's a good quality product and it's well protected. It's got a fuse here. The solenoid's grounded directly to the inaudible 00:07:07 vehicle. It's a good product. Brent: One thing I really like about it is when you pull it out of the box it's already wired for you too. You don't have to worry about which cable goes where. You don't have to make sure if you have the trigger solenoid hooked up to the right one or the ground solenoid hooked up to the right one. It's already done for you so it makes this very easy. Plus, it's labeled so you know what goes where. It's very, very simple. You almost don't even need the instructions to install it since it's labeled so well. Speaker 2: All right. Thanks guys.


Info for this part was:

Employee Jeff D
Installed by:
Jeff D
Employee Joshua S
Video Edited:
Joshua S
Employee Jacob T
Video Edited:
Jacob T
Employee Kathleen M
Video Edited:
Kathleen M
Employee Dustin K
Video Edited:
Dustin K
Employee Chris R
Video Edited:
Chris R
Employee Randy B
Test Fit:
Randy B
Employee Andrew S
Test Fit:
Andrew S
Employee Brent H
Test Fit:
Brent H
Employee Shane H
Test Fit:
Shane H
Employee Robert C
Test Fit:
Robert C
Employee Conner L
Test Fit:
Conner L
Employee David F
Test Fit:
David F
Employee Ryan G
Test Fit:
Ryan G
Employee Clayton O
Test Fit:
Clayton O
Employee Kevin C
Test Fit:
Kevin C
Employee Bradley B
Test Fit:
Bradley B
Employee Zach D
Video by:
Zach D
Employee Jonathan Y
Video by:
Jonathan Y
Employee Michael B
Video by:
Michael B
Employee Jacob H
Video by:
Jacob H
Employee Aidan B
Video by:
Aidan B
Employee Thomas T
Video by:
Thomas T
Employee Charles A
Video by:
Charles A

At etrailer.com we provide the best information available about the products we sell. We take the quality of our information seriously so that you can get the right part the first time. Let us know if anything is missing or if you have any questions.