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Roadmaster Hy-Power Diode - (Qty 1)

Roadmaster Hy-Power Diode - (Qty 1)

Item # RM-790
Retail:$31.63
Our Price: $13.94
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RM-790 - Diodes Roadmaster Accessories and Parts
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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 (283)
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  • Videos (2)
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Roadmaster Accessories and Parts - RM-790

  • Tow Bar Wiring
  • 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





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 Roadmaster Hy-Power Diode Review

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:


Customer Reviews

Roadmaster Hy-Power Diode - (Qty 1) - RM-790

Average Customer Rating:  4.8 out of 5 stars   (282 Customer 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.

by:

I needed to add the diode to the wiring to complete installing the Brake-Lite relay. etrailer made it easy to order and receive it.



by:

etrailer is a breeze to work with and always has what I need. Not sure yet on the quality of these parts, they are replacements for some installed less than a year ago. We'll see if these next 2 last a little longer.



by:

Great little part that does the perfect job of protecting my electrical circuit between my fifth-wheel trailer and my truck. It does a great job of keeping the 12 volt power flowing in the correct/one-way direction.



by:

I have placed a few orders with etrailer and have been very satisfied with the quality and arrival time of each order.



by:

E trailer is easy to work with and has great product support.



by:

Product shipped promptly and arrived in good condition and on time…



by:

easy install, after a year, no issues



by:

Works fine. Problem ended up being a faulty bulb. Worked intermittently



by:

I was missing a part and they overnighted it. Great service



by:

I needed to charge my tow vehicle battery by taping in to my tail lights on my motor home. This will prevent The tail lights on the tow vehicle from feeding from its own battery. My break buddy was depleting the tow vehicle battery on long trips. Solved my problem!

Jon L.

6/20/2019

Working great, no problems



by:

Works as expected. Keeps the flow of AC output on my alternator from backing into my distributor high-tension lead and not allowing my boat engine to shut off with the key.



by:

Bought this so I could install backup lights on my trailer and also be able to use them as loading light. This has worked out great. I have also purchased several other items from etrailer and have been happy with all of them.

James S.

11/21/2018

After a year this Diode has ben flawless works great for my application.



by:

Exactly what I needed. Easy installatio n.



by:

This diode was easily installed and functions extremely well, as do all of the products we have purchased from etrailer.com. etrailer's extremely competitive prices, their outstanding customer service, and their free, quick delivery make them our go to company for all of our towing needs.

George C.

7/31/2015

The products are performing perfectly!

George C.

8/4/2015

We love the equipment that we purchased from you. We have had no issues with towing our Miata.Thank you for your correspondence.



by:

Put it in a snowmobile trailer with a battery and hook the clearance light wire with the one way diode & then to the interior lights so if someone leaves the lights on in the trailer we can still start the pickup when we get back from a 3 day ride



by:

Nice item, problem solved with my auxiliary lights on the rear of my pickup, lights now work off two switches and no feed back either source. Can put truck in reverse and it doesn't feed power back to switch or i can manually turn them on from the switch and no back feed to my reverse lights. Was nice that it came with butt connectors even tho i have all the electrical connectors, didn't have to search for any. Liked how you can put two power source in and it goes out to one and didn't have to buy two diodes one for each side like traditional diodes. All around nice product and well made. Sorry didn't have a pic to post with it didn't feel like pulling taillight back out.



by:

Fantastic. The advice received from E-Trailer was perfect. The Diode was exactly what I needed. Small, inexpensive, and very effective. The adhesive back and included connectors couldn't have been a better fit.

Needed this to prevent backfeeding of a Motorcycle Lift Battery in my pickup from powering the truck. Truck required a disconnect of the negative battery cable before towing behind a motorhome.



by:

I was amazed to learn that similar to plumbing, you can put a one way valve in a 12 volt wire as well. One of my batteries was not being charged when our RV was plugged in and to make sure I did not run down my engine battery I installed this diode. Simple and came with connections ready to be hooked up. Arrived pretty quickly too. That you Christina J for one on one over the phone help.



by:

I bought all Roadmaster parts for my tow car.
ALL worked as advertised(GREAT)
I thought about a 4 star because slow delivery
but you all were helpful.



by:

I always have trouble receiving deliveries because I have a postal address that doesn't accept FedEx or UPS and a physical address that doesn't accept USPS. The website doesn't specify the shipping method, so I sent a note to customer service. The rep personally oversaw my shipment so that I got it quickly and at the right destination. It's that kind of service that keeps me coming back to etrailer.com



by:

I added accessory back up lights to my truck. I wanted them to work with the truck back up lights and be able to turn them on with a switch in the cab. I did not want to chance backfeed when I used the switch, so I bought this. Only have had it installed for a week and no problems works the way I wanted it to.



by:

I am in awe how quickly this order was processed and delivered. Considering it had to clear Canadian customs and I ordered on a Friday , it was in my hands on Wednesday.
Megan was very helpful on the phone in locating the correct parts ,processing the order and following up with tracking info. I had also chat online prior to placing the order with Mackenzie who answered all questions effectively.
Combining all this with the fact etrailer has very detailed instructions with drawings on the installation and I am beyond impressed. It isn’t often we see customer service on this caliber today. As a consumer I will definitely be using them again!
Oh yeah and the product needed was in stock whereas when I ordered from a well known online site (A...n) in September and told ETA would be Nov/Dec they couldn’t even deliver in that timeline?



by:

I used this diode to connect a 12v line from my coach battery to the battery on my CR-V. It helps to keep the CR-V battery from discharging while towing.



by:

Used on spray equipment wiring to run a foamer with an on/off/on (L-R) switch. Had to eliminate a feedback loop with a high amp diode to run an actuator, this item fit the bill very nicely.



by:

I bought these electrical products for my brother‘s Fiat that he tows behind his moterhome for extra parts haven’t had to use them yet but it’s good to know that etrailer Corp. has the parts thanks George J.


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See what our Experts say about this Roadmaster Accessories and Parts

  • Diode Kit for Flat Towing 2012 Ford Focus
    We do have flat towing diode kits for the various versions of the 2012 Ford Focus, such as # RM-154, that you can see on the linked page. You can use the Select Vehicle Style drop-down menu bar at the top of the page to choose your Focus and then see suitable kits. We also have individual diodes # RM-790 and # RM-690 as well as 2-pack # RM-792 and 4-pack # RM-794. All of these come with spade terminals that accept wire leads.
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  • 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...
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  • Troubleshooting Tail Light Flashing with Flexo-Coil Kit Installed on 2018 Jeep JL Wrangler Unlimited
    Start off by checking the 6-Way connector at the front of your 2018 Jeep JL Wrangler Unlimited. Be sure that none of the wires are touching any wires next to it which would allow power to jump from one circuit to the other. If that looks good then the next step is to troubleshoot the diodes that come with the Flexo-Coil Wiring Kit # RM-15267. Since the problem is only happening to one side simply remove the diode on the circuit that is messing up and swap it with one on the other side...
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  • Wiring Needed For Flat Towing a 2022 Ford F-150 Hybrid With LED Tail Lights
    You can use standard Diodes # RM-790 on your 2022 Ford F-150 Hybrid with the LED tail lights. I recommend using the Roadmaster Diode 7-Wire to 6-Wire Flexo-Coil Wiring Kit # RM-15267 as your F-150 will also need a Charge Line Kit # RM-156-25 to prevent the battery from being drained while towing.
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  • Diode Installation to Allow Both Low Beam and DRL Circuits to Feed Add-On LED Light Strip
    Roadmaster Diode # RM-790 can handle up to 85-amps of current so one should be sufficient to handle both the low beam and daytime running light circuit input signals you want to feed to your LED strip light. It is fine to have two hot leads connected to the one diode so long as the total rating is high enough.
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  • Is a Relay Required for Normally Closed Installation of Brake Light Relay on a 2015 Jeep Cherokee
    To determine if you need to use diode # RM-790 on the normally closed installation of the brake light relay # RM-88400 perform this test: Start the engine and turn on the headlights. With a volt meter, such as # PT89ZR is you need one, test the tail light wire for 12 VDC+ current at any point between the splice made into the tow bar wiring you are using and the brown wire in the relay kit and the tail lights. If the volt meter does not register voltage, a diode is not needed. If the...
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  • Is The Roadmaster Diode # RM-790 Necessary For Installing The # RM-88400 On A 2019 Jeep Cherokee
    The # RM-790 isn't always typical for installation which is why it's listed as possibly being needed. If you start your engine and turn on your headlights and then test the tail light wire with a voltmeter like # PT89ZR and do register 12VDC then you will need to install the diode to protect your vehicle's components from harmful feedback.
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  • Replacement Diode to Use on a 1999 Jeep Grand Cherokee
    If you were needing a single diode then you are looking for part # RM-790, if you need a set of diodes then it will be # RM-792. If you are needing to use 4 diodes, the part is # RM-794.
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  • Resistance on the Roadmaster Diode 790
    I spoke to my contact at Roadmaster and he said that the diode part # RM-790 would have a very minimal amount of resistance. He said that as long as you install the diode properly there would be no way it would generate any trailer light error codes that would pop on your vehicle. I went and grabbed one of these diodes from our warehouse to measure the resistance with an Ohmmeter we have here and found it to show .7 ohms when the Ohmmeter was on the 200 setting.
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  • 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.
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    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...
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  • Can/Should 2020 Jeep Cherokee Sport Flat Tow Running Light Wiring Be Connected to Headlights
    Sure, you could integrate 2 more of the Roadmaster Hy-Power Diode # RM-790 into the Roadmaster Flexo-Coil Wiring Kit # RM-15267 on your 2020 Jeep Cherokee Sport to have the running lights on while you're towing, but it would be easier to just splice into the running light circuit from the motorhome up towards the front of the vehicle by using a Butt Connector # DW05744-5 and a length of 16 Gauge Wire # 16-1-1 so you aren't running more wire from the back of the vehicle to the front. With...
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  • Replacement Roadmaster Diode Recommendation
    Part number # RM-794 is for 4 diodes, so while it would work for you a better option would be to order a quantity of 3 of the part # RM-790 as that is a single diode.
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  • Can Roadmaster Diodes Be Purchased Separately
    Yes, the diodes of the Diode Kit part # 154-792-118158 are available separately. They are available individually in the part # RM-790. If you need 6 like what the # 154-792-118158 has you would need to order a quantity of 6.
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  • Is Diode Needed For 2022 Ford Expeidtion Using Brake-Lite Relay
    Hi Chris; your 2022 Ford Expedition will have a Normally Closed application, and it is possible when installing the Roadmaster Brake-Lite Relay Kit # RM-88400 that you'll need Hy-Power Diode # RM-790. I can't say for sure because it's really dependent on the vehicle and type of wiring you use. You'll need to test by turning on the headlights and testing for voltage at the red wire of the relay. If there is voltage use # RM-790. As for the wire color, per Roadmaster, the 2022 Expedition...
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  • Additional Parts Needed To Separate Turn And Brake Light Signals On A Flat Towed Vehicle
    The Tail Light Isolating Diode System with Wiring Harness # 38955 would be a complete replacement of the current diode wiring so you can replace it all and add in the converter # C56196 and two additional diodes # RM-790 to get your separate lighting. You could also just splice in the converter and additional diodes instead of replacing the current wiring.
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  • Can Regular Hy-Power Diodes Be Used On Constant Voltage LED Lights
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    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...
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  • Installation of Brake Light Relay on 2017 Jeep Cherokee with SMI Stay-In-Play DUO Braking System
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    I spoke with our installation manager and found out that the third brake light on newer Jeeps like your 2017 never light up in these situations. The issue is that it is on its own circuit and the brake light relay, which allows the turn signal lights to function properly when braking, doesn't allow the third brake light to illuminate. It is possible to get it to light up but you would have to have another converter, # 118158, which would tap into the combined right turn/brake and left/turn...
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  • Back Feed Protection from Breakaway Switch to Protect Brake Controller
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  • Wiring Exterior Trailer Lights to be Powered by Reverse Circuit and On Board Battery
    In order to wire your exterior hi-mount trailer lights so that they are powered by the reverse light circuit on your Ram but can also be powered by the on board battery, you will just need to use a diode like the Roadmaster # RM-790. The output side of the diode will go to your exterior LED lights, while the input side will go to the center pin on your 7-Way and also to your on board battery via a switch like # PK34308. I also recommend adding a circuit breaker like # 9506P before the battery....
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