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Roadmaster Hy-Power Diode - (Qty 1)
Roadmaster

Roadmaster Hy-Power Diode - (Qty 1)

Part Number: RM-790
$16.63
Retail:$33.62
You Save: 51%
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Diodes permit electrical current to flow in only one direction - from the motorhome to the car - prevents electrical feedback and the damage it can cause to the towed car's electrical components. 1-800-940-8924 to order Roadmaster accessories and parts part number RM-790 or order online at etrailer.com. Free expert support on all Roadmaster products. Great prices and Fastest Shipping for Roadmaster Hy-Power Diode - (Qty 1). Accessories and Parts reviews from real customers.
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  • Reviews (320)
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Roadmaster Accessories and Parts - RM-790

  • Flat Tow Wiring Harness
  • Diodes
  • Roadmaster

Diodes permit electrical current to flow in only one direction - from the motorhome to the car - prevents electrical feedback and the damage it can cause to the towed car's electrical components.


Features:

  • Diodes permit electrical current to flow in only one direction - from the motorhome to the car
    • Enables trouble free operation of your towed vehicle lights
    • Prevents damage to your towed vehicle's electrical components
  • Maximum load per diode: 85 amps at 12 volts
  • Includes detailed wiring instructions
  • Qty: (1) Diodes
  • Made in the USA



Note: 4 Diodes are required for most applications (1 left turn/brake, 1 right turn/brake, 2 for tail lights - each side).




790 Roadmaster Hy-Power Diode




California residents: click here


Video of Roadmaster Hy-Power Diode - (Qty 1)

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.




Video Transcript for Checking Out the Roadmaster Hy-Power Diode

Brad Hello neighbors it's Brad here at etrailer and today we're taking a look at the Roadmaster replacement wiring diode. Now this is available in a quantity of one, two, three or four and this is going to simply just replace an old diode that might have gone bad or if the tab broke. Either way, instead of having to buy a whole new kit, you can simply replace just the diode and that is really nice because the diode is actually user factory wiring that run through them so you still keep your factory lights working properly but if the diode fills, it is very possible that your stop and turn signal as well as your running might not work. So a simple replacement by just taking off the old spade connectors and replacing it can fix that pretty easily. Now only if you do have one that is going bad or you do suspect that, the first thing I would check is definitely the wiring first just to make sure that it is properly connected, but if you deem that this needs to be replaced, no problem. This is going to be a direct replacement.

In fact, if you want, there is actually new spade connectors that are included with the diode so that way you can replace that as well. And if you need to pick up the yellow spade connector here for your cross over wire. You can actually purchase that individually and that way you can really just piece together whatever kit you may need and if you buy multiple quantities, you can actually have an extra set on hands. But having a replacement can get you back on the road and keep you safe and legal. Now these do tend to be extremely reliable.

We don't really have too many people that have issues with them, but it is an electronic component and things can fail especially after a long period of time. So being able to just swap this in and be back on the road flat towing your vehicle safe and legally. It is kind if nice to just be able to replace the diode..

Customer Satisfaction Score:

Ratings & Reviews

4.8

319 reviews
Diodes permit electrical current to flow in only one direction - from the motorhome to the car - prevents electrical feedback and the damage it can cause to the towed car's electrical components.

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See what our Experts say about this Roadmaster Accessories and Parts

  • Specifications for Roadmaster Diodes # RM-690 and # RM-790 for Use on a Semi-Trailer
    I do have some technical information for you about the Roadmaster Diodes # RM-690 and # RM-790, but I do not have any prints available. Both part numbers are 1/2" tall, 1-9/16" wide, and are 1-5/16" long. They can withstand up to 85 of continuous amps, plus they have been tested to work when they are frozen and tested in an oven up to 180 C without failing. My contact at Roadmaster said that these can definitely take a beating and will work great for your application.
    view full answer...
  • Troubleshooting Incompatibility Error Brake Controller 2024 Chevy Silverado 3500
    Does your trailer have solar panels? We've heard of this issue and and it appears there is a tech bulletin out about how the solar panel kits on trailers make the truck have this issue and disconnecting helps. The tech bulletin is 23-NA-113 and we've heard they are working on a fix for it. One person was able to get it to work by installing the # HBA-CAM on their trucks' trailer wiring so that's an option too.
    view full answer...
  • Troubleshooting Vehicle with Diode Tow Bar Wiring Kit That Brake Lights Stopped Working
    Sounds like maybe the diode of the wiring kit on your vehicle has gone bad. You can bypass the diode to get the brake light to get it to work again, or you can replace the diode with part # RM-790 for if you ever planned to flat tow the vehicle again. If your brake lights are separate from your turn signals you could do what you described and run the brake light wire from one side of the vehicle to the other taillight, but you would also run the risk of overdrawing that circuit since it...
    view full answer...
  • Can Roadmaster Hy-Power Diode Work with 37 Amps at 10V Input
    The Roadmaster Hy-Power Diode # RM-790 is rated for a max of 85 amps at 12 volts. If you meant to say 37 amps at 10V then this should work out just fine!
    view full answer...
  • Can I Use Roadmaster Diodes RM-790 On A 2024 Chevy Equinox LT?
    Hello Louis. No, you cannot use the # RM-790 diodes on the 2024 Chevy Equinox LT. This vehicle requires a smart diode kit, so the standard diodes will not work. The 2024 Chevy Equinox LT uses the following: - Roadmaster Smart Diode 7-Wire to 6-Wire Wiring Kit for Variable Voltage Incandescent Tail Lights # RM26FR Or if you already have a coiled cable and 6-pin plug use part # RO94FR.
    view full answer...
  • Combining Brake and Turn Signals on 2001 Jeep Cherokee
    From what it sounds like you are trying to take your 2001 Jeep Cherokee's separate brake and turn signals and combine them into one. If that's accurate, what will need instead of the diodes is a 3-to-2 converter, the Roadmaster Brite-Lite Wiring Converter # RM-732. I have added a link to a video review and manual for you to check out of this part.
    view full answer...
  • Can Diodes be Used To Connect Two Power Sources To A Radiator Fan
    Diodes like the # RM-790 are just to prevent feedback by allowing electricity to only flow one way and wouldn't provide the same function as a transfer switch to go between the two power sources, if that's what your goal is. You would need a automotive grade relay with two trigger wires to separate the two power sources so that the fan can be triggered by the ECU at the set temperature and with your switch.
    view full answer...
  • How to Fix Backfeed From Trailer Battery and Solar Controller on 2024 GMC Sierra 2500
    Installation of the # RM-790 will take care of that problem you're having. I would wire it on the trailer side at the battery rather than mess with the wiring on your 2024 Sierra 2500. The other solution is to follow the GM note and add a disconnect between the battery and solar controller like other trailer manufacturers have started to do. If you want to go that route you can use the # SE29VR.
    view full answer...
  • Troubleshooting Non-Working Diode Wiring Kit On A 2015 Fiat 500
    If nothing at all is working then the ground wire for your Roadmaster Diode 7-Wire to 6-Wire Flexo-Coil Wiring Kit # RM-15267 is likely the issue. I recommend checking that it's making a good connection to the frame of the vehicle and isn't starting to corrode. If that isn't the issue then you'll need to connect to the motorhome or another vehicle with a 7-way connector and then put on your light signal (you can just start with running lights) and then trace the wires back starting at the...
    view full answer...
  • Parts Needed To Flat Tow A 2023 Ford Ranger
    The Roadmaster Direct-Connect Base Plate Kit # RM-524459-5 would be a great option for the baseplate. If you don't already have a tow bar to complete the connection to the motorhome then I recommend the etrailer SD Non-Binding Tow Bar for Roadmaster Direct-Connect Base Plates # e74ZR. Since you're reusing your power cord and socket you'll really only need the Roadmaster Universal Hy-Power Diode Wiring Kit # RM-152. The charge line kit # RM-156-25 is a great choice to make sure that your...
    view full answer...
  • How to Prevent Breakaway Battery From Draining Winch Battery Power
    If I'm understanding you correctly the starter solenoid # PK5231201 is not the solution to your problem. Based on what you have described, it sounds like both the breakaway battery and winch battery are hooked to the 12V power coming from your 7-way. This is what I would expect to see, and would allow for a maintenance charge on both when hooked up to the tow vehicle. However, with the winch battery and breakaway battery on the same circuit you see the breakaway battery constantly charging...
    view full answer...
  • Is Diode Needed to Prevent Trailer Battery from Backfeeding to Breakaway System
    Yes, you will want to use a single function diode, like part # RM-690. You will need to wire it in between the breakaway battery and the trailer battery to stop the backfeeding from the battery to the breakaway system.
    view full answer...
  • Are the Roadmaster Hy-Power Diodes Water Tight
    As long as you are not exceeding the 85 amps at 12 volts per diode max load then you can definitely use the configuration in your diagram. I spoke with my contact at Roadmaster who said that the connections are not watertight but the internal components are. You would either need to find a way to make the connections watertight (as you mentioned in your diagram) or simply wipe the connections off if you were to go off-road with your 2011 Jeep Wrangler and get the diode(s) wet. We have...
    view full answer...
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  • Diode to Prevent Back Feeding from Trailer Battery to Running Lights
    For a diode I recommend # RM-790 which is rated for 85 amps. However, trailer wiring, both on the trailer and on the vehicle side, is too small to charge up a regular battery. And most vehicle alternators are unable to push back the amperage required to charge up a regular battery. At best it will provide a maintenance charge and keep the battery from depleting. It can charge up a small breakaway batter such as # HM20008 though. But these batteries are rated much lower than a regular car...
    view full answer...
  • Can Roadmaster Diode # RM-790 be Used to Prevent Backfeeding to Vehicle
    The diode part # RM-790 will prevent the circuit from backfeeding to the tow vehicle. Basically you would pick one of the spades on the IN side of the diode for the side of the wiring from the trailer connector and then the OUT side would go to the battery.
    view full answer...
  • Can Regular Hy-Power Diodes Be Used On Constant Voltage LED Lights
    Yes, the standard diodes like the Roadmaster Hy-Power Diode # RM-790 will work with constant voltage LED lights. The Roadmaster Smart Diodes for Variable Voltage LED Tail Lights # RO54FR you were looking at are designed for use on variable voltage LED tail lights, which on typically found in Jeeps with ParkSense Proximity Sensors. If you provide me with the year/make/model of the vehicle you're wanting to flat tow I'd be happy to find the correct components to get you out on the road.
    view full answer...
  • Will the Brakeaway Battery Backfeed into My Tow Vehicles Battery?
    I believe you are talking about the brakeaway switch on your trailer such as the Hopkins # 20400. The only occurrence when that battery backfeeds into the Tesla battery is if the pin is pulled in the event of the brakeaway. If that pin is not pulled on the brakeaway switch, there will not be any feeding into your Tesla's battery. If you are still concerned, you can always install the Roadmaster Hy-Power Diode - (Qty 1) # RM-790 so that it is impossible for the current to backfeed into...
    view full answer...
  • Availability of Just the Diodes in the Roadmaster Diode Kit # RM-154
    Sounds like you are looking for just the diodes of the # RM-154, which we do have as part # RM-790.
    view full answer...
  • Electric Brakes are Pulsating When Vehicle Hazards are Activated
    I have a solutions for your pulsating electric brake issue. Installing the tow Ready Pulse Preventer for Electric Brake Controllers, # 5501, will help eliminate the pulsing in your electric brakes, especially if you have the brake controller set at an aggressive setting. The attached diagram will explain the basic installation of the pulse preventer for you to review.
    view full answer...
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  • Can Reverse Light on Trailer Also be Powered with Switch In Truck
    You can do this but you'd need to use a diode installed on the circuit so that the switched power won't backfeed onto the vehicle reverse lights. So what you can do is wire both the reverse light circuit and the switched power source to the input side of the # RM-790 and then the output side to the circuit and you'll accomplish what you are looking for.
    view full answer...
  • How To Prevent Back Feed From A Deep Cycle Battery On Your Trailer
    A diode is designed to stop the reverse flow of current in an electrical circuit. Therefore yes, a diode will prevent backfeed to your vehicle from the trailer's battery. The part you referenced part # RM-790 has a dual in, single out function generally used on taillights with multiple power sources. In your case, you will want the Roadmaster Single Park Light Diode part # RM-690 in order to eliminate back feed. To install the diode, you will need to severe the 12 volt hot lead from the...
    view full answer...
  • Can The Ultra Bright LED Lights Be Used For Backing up
    Yes The Ultra Bright LED Flood Light # 3371492196 can be used as a backup light when connecting to your reverse blue wire from the 7 plug, but you need to make sure that the circuit can handle the power of the light. Each light runs 6.25 amps, since you're running two you will need at least 12.50 amps for them to function properly. They can also attach to your current battery setup when the truck is not running. To add a switch. You can install diode # RM-790 (for one each light) inline...
    view full answer...
  • Replacing 6-Pin Square Trailer Connector on Jayco Pop-Up Camper With a 4-Way Flat
    It sounds like you are replacing your older 6-pole wiring harness on your Jayco popup camper to a 4-flat connector like # HM48110. When you do this, you will have the black auxiliary wire and the blue brake wire remaining. You will no longer be able to use those functions, so those wires can just be taped up and stowed out of the way. The 4-Way trailer end functions are brown for running light circuit, white is the ground, green is right turn/stop, and yellow is left turn/stop. In regards...
    view full answer...
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  • Does Roadmaster Hy-Power Diode Have Any Voltage Drop
    The Roadmaster Hy-Power Diodes haven't been tested for voltage drop since they are designed to be a pass-thru device that just keeps backfeeding from happening. When I reached out to my contact at Roadmaster they said that the voltage drop would be very minimal if anything. I like the Hy-Power Diodes because of how durable and effective they are. You can get this diode in a handful of qunatities: 1 - # RM-790 2 - # RM-792 3 - # RM-793 4 - # RM-794
    view full answer...


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