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Roadmaster Hy-Power Diode - (Qty 1)
(113 reviews)
Price: $12.09
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Roadmaster Hy-Power Diode - (Qty 1)
Item # RM-790
Retail:$25.99
Our Price: $12.09
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- Reviews (113)
- Q & A (66)
- Videos (1)
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Roadmaster Accessories and Parts - RM-790
- Tow Bar Wiring
- Diodes
- Roadmaster
Roadmaster Hy-Power Diode
Diodes permit electrical current to flow in only one direction - from the motorhome to the car - preventing electrical feedback and the damage it can cause to the towed car's electrical components.
Features:
- Qty: (1) Diodes
- Reduces wiring hassles
- Trouble free operation
- Includes detailed wiring instructions
- Maximum load is 6 amps at 12 volts per diode
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 Review of Roadmaster Tow Bar Wiring - RM-790
Today we're going to take a look at the Roadmaster High Power Diode for a quantity of one. Now this diode will allow your motor home or RV to power the lights on your towed vehicle without power feedback.The diode's will permit electrical current to flow in one direction, from the motor home to the car, preventing any electrical feedback and the damage that can cause to the towed car's electrical components. Now this part is for a quantity of one diode. It is available in a variety of quantities, so you can get a one pack, a two pack, a three pack, or even a four pack, and all options are available at etrailer.com.For the one pack like this one, you use part number RM-790, a two pack would be RM-792, a three pack would be RM-793, and the four pack would be the RM-794.Now this does reduce wiring hassles. The spade connectors right here allow for easy trouble-free wiring connections and the aluminum heat seek design on this style, it helps prevent overheating. On the very back it has a self stick pad that you can peel on that allows for easy and secure mounting.
Maximum load on this is six amps at 12 volts per diode and one note on this is usually four diodes are required for most applications, one for the left turn and brake, one for the right turn and brake, and then two for the taillights, one on each side.But that should do it for the review on the Roadmaster High Power Diode for a quantity of one.
Customer Reviews
Roadmaster Hy-Power Diode - (Qty 1) - RM-790
Average Customer Rating: 4.9 out of 5 stars (113 Customer Reviews)
- RM-790
by: Works great08/27/2014
Needed to set up a circuit to activate my reverse lights on the trailer to light up the loading ramp. This worked great to keep the power from backfeeding into the car. 148921
- RM-790
Jon l - 06/20/2019
56873
by: Jon l.06/20/2018
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! 524458
Comments
Working great, no problems
Jon l - 06/20/201956873
- RM-790
Jim - 07/06/2018
40570
by: Jim07/06/2017
Ordered a diode for a project on my RV and it worked out fine. I just wish the price was much cheaper for such a small part. 402096
Comments
Ok
Jim - 07/06/201840570
- RM-790
by: James12/31/2017
This is a little premature to give a product rating. I will say that the diods iordered arrived sooner than expected. After reviewing the options for wiring a vehicle to be towed behind a mtrhome this is the way to process. Thank you, Jim 464083
- RM-790
by: Dion10/02/2018
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. 570830
- RM-790
by: Roy S.03/04/2015
I ordered the product to install in my 2014 VW. The next morning I got a call that what I had ordered would not ship right away and they told me if I didn't mind they could put everything I needed together and ship it right out. The he asked what I was going to use this for and It happened to be what I needed.i installed it today and it works great. 177040
- RM-790
by: Bryan02/15/2020
Easy to install. Took awhile for me to understand installation but working well a year later 751598
- RM-790
by: Paul12/05/2019
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? 729438
- RM-790
by: SimiSteve04/11/2019
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. 621601
- RM-790
by: Brian S03/26/2019
So far so good 614214
- RM-790
by: Donald03/09/2019
Good product works well one leg to camper batttery one leg from truck to camper batteries 610816
- RM-790
by: Randy02/18/2019
Diode was delivered promptly and was a good transaction, Very pleased with the service 606072
- RM-790
by: Jack10/23/2018
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. 576776
- RM-790
by: Tom10/03/2018
Fits perfectly and works great without overheating. 571395
- RM-790
by: Karen08/17/2018
glad we could find it here. 554841
- RM-790
by: Dennis06/12/2018
Excellent service. 521452
- RM-790
by: Kim04/24/2018
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. 500181
- RM-790
by: Layne04/07/2018
Just installed it. I think it’s working. I like that the spade terminals are included. 493819
- RM-790
by: Shane04/05/2018
Works great!!! 493044
- RM-790
by: Richard02/24/2018
has worked great. 478527
- RM-790
by: Larry02/22/2018
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 477933
- RM-790
by: Thomas02/04/2018
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. 472833
- RM-790
by: Bud12/28/2017
Just what I was looking for small and compact also 463406
- RM-790
JAMES S - 11/21/2018
45910
by: James11/21/2017
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. 454001
Comments
After a year this Diode has ben flawless works great for my application.
JAMES S - 11/21/201845910
- RM-790
by: Myron11/09/2017
Used diode in wiring dingy battery to RV to keep it charged while towing - worked great. 450358
25
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Ask the Experts about this Roadmaster Accessories and Parts
- How To Prevent Back Feed From A Deep Cycle Battery On Your TrailerA 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...
view full answer... - Is Diode Needed to Prevent Trailer Battery from Backfeeding to Breakaway SystemYes, 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... - Can Roadmaster Diode # RM-790 be TestedIf you ran a jumper wire from a 12 volt battery to the input side of the Roadmaster Hy-Power Diode # RM-790 and then used a circuit tester like part # PTW2993 to test the output pin for 12 volts you'd know if the diode was good or not.
view full answer... - Troubleshooting Vehicle with Diode Tow Bar Wiring Kit That Brake Lights Stopped WorkingSounds 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...
view full answer... - Amperage Rating Difference Between Roadmaster RM-790 and RM-690The # RM-690 has a 85 amp capacity and the # RM-790 also has an 85 amp capacity. For preventing backfeed on a circuit either diode will work just fine as long as the amperage of your setup stays under the rating for either diode. The biggest advantage the # RM-790 has other than the higher capacity is that it can be used with two different inputs.
view full answer... - Diode Recommendation for Preventing Current Backfeed on Trailer 7-Way 12 Volt Power CircuitFor a single diode to prevent current backfeed the part # RM-790 would be a great option. Just install this on the 12 volt circuit of the 7-way and you would be set. This has a amp rating of 85 amps.
view full answer... - How to Use Diodes to Have Two Batteries Power a Circuit with No FeedbackYour black drawing would be how wire up the # RM-790 so that both batteries would be on the same circuit but with feedback prevented on the circuits back to the batteries or having them tied together. Basically you would use a diode on each battery line. Using one diode for both batteries would only allow one battery to power the circuit at a time.
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- Using Roadmaster Hy-Power Diode to Prevent Back-feeding With Trailer LightsThe Roadmaster Hy-Power Diode # RM-790 will work well to prevent back-feeding for your application. You will only need one diode for the system. The wire from the trailer connector will connect at one post on the "in" side, and the wire from the switch will connect at the other post on the "in" side. The wires going to the lights will come from the post on the "out" side.
view full answer... - Back Feed Protection from Breakaway Switch to Protect Brake ControllerYou can use a diode # RM-790 to protect your brake controller. Some brake controllers, like the Prodigy P2 # 90885 and P3 # 90195, already have back feed protection built into them.
view full answer... - Diode Recommendation for Preventing Backfeeding with Two Power Sources to One Electric MotorThe Roadmaster Diode part # RM-790 would be exactly what you'd need. It allows two power sources on the input side and only one on the other side which means that one power source couldn't backfeed onto the other. This isn't overkill at all and would be an ideal solution.
view full answer... - Why Do Diodes have Two Input Terminals and Only One OutputDiodes like the part # RM-790 have two wires on the input side so that you can have two different power sources activating a single circuit (the out side) and not have to worry about the power circuits backfeeding on each other.
view full answer... - Resistance on the Roadmaster Diode 790I 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.
view full answer... - Can Roadmaster Diode # RM-790 be Used to Prevent Backfeeding to VehicleThe 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... - Diode Recommendation for Preventing Current Backfeed on 12 Volt Power CircuitFor a single diode to prevent current backfeed the part # RM-790 would be a great option.
view full answer... - Shutting Off Power on 12 Volt Hot Lead so Trailer Does Not Drain Battery on 2012 Chevy SilveradoYou will actually need a battery isolation solenoid, # TR118665. A diode won't be able to do what you want it to do. The solenoid can be installed on the 12 volt power wire going to the trailer connector on your 2012 Chevy Silverado. What happens is when the truck is turned off it will shut off power to that circuit. I have included a picture pointing out what each of the studs is for on the isolator. The 12 volt ignition source is something that only has power when the truck is turned...
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- Diode Installation to Allow Both Low Beam and DRL Circuits to Feed Add-On LED Light StripRoadmaster 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.
view full answer... - What Would Happen if a Diode Received Power on Both Inputs at the Same TimeIf the two power sources are going to be on the same, input side of the diode then the current would flow through it without an issue. If you put power on both sides of the input side of the # RM-790 the current on the output side of the diode would not be affected. Basically the higher current on the two inputs would be the circuit that would make it to the output side. If the current was put on the output side of the diode it would not travel through the diode. Diodes like the part...
view full answer... - Will Roadmaster Diode # RM-790 Prevent Trailer From BackfeedingYes, the Roadmaster Diode part # RM-790 will prevent the trailer from backfeeding to the battery of your Jeep. You would just need to install it inline with the 12 volt accessory circuit and you would be set.
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.
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- Would Roadmaster Diode part # RM-790 Work to Combine Running and Brake Lights on One CircuitIf you were looking for a way to have a single circuit be activated by either your running lights or brake lights the diode part # RM-790 would work for this. The side of the diode with two terminals would take both of the circuits you mentioned and the single side of the diode would go where needed.
view full answer... - Can a Diode be Used to Power Lights from 2 Different Power SourcesYou hit the nail right square on the head. Using diode # RM-790 as you have described will allow you to power the lights from 2 different sources (one at a time) without back feeding. It would be best to mount the diode where it is protected from the elements. We also have 10 amp on/off toggle switch # PK34513 that you could mount somewhere on the truck. One wire would go to the vehicle battery and the other would go to one of the inputs on the diode.
view full answer... - Are Diodes Required to Install Trailer Wiring for a 1999 Jeep Grand Cherokee to Tow a TrailerTo wire your 1999 Jeep Cherokee for towing a trailer, you will need to use a converter, to convert the 3 wire system on your Cherokee to the standard combined 2 wire system that is used on US made trailers. Separate diodes are not required. The correct wiring harness for your 1999 Jeep Grand Cherokee is the T-One Vehicle Wiring Harness, # 118369. We have an installation video that shows this harness being installed on a 1999 model for you to review. The wiring harness and converter...
view full answer... - Amperage and Voltage Rating of the Roadmaster Hy-Power Diode # RM-790I spoke with my contact at RoadMaster and the maximum voltage of the Roadmaster Hy-Power Diode, item # RM-790, is 24 volts. The maximum amperage is 85 amps. These are silicon resistors.
view full answer... - Explanation of How Diode RM-790 Prevents Circuit BackfeedingDiodes like the part # RM-790 only allow current to flow in one direction. Usually a diode is a small cylindrical shaped component (not in this case) which has two leads on it, the anode and the cathode. When the anode side of the diode is facing towards the positive power source of the voltage it will allow the circuit to be completed and is considered "forward biased." If the cathode side of the diode is facing towards the positive side of the voltage then the diode will not allow...
view full answer... - Are the Roadmaster Hy-Power Diodes Water TightAs long as you are not exceeding the 6 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...
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- Diode Recommendation for Taking Two Power Sources from Solar Panels The diode part # RM-790 that you referenced does exactly what you are looking to do. It takes two power sources and can combine them onto one wire and prevents backfeeding from either circuit. So for what you need this would work well.
view full answer... - Can Roadmaster Diode RM-790 be Used for Aftermarket LED Headlight InstallDiodes like the Roadmaster Hy-Power Diode # RM-790 can be used for a wide variety of applications! If your LED headlights are going to be receiving power from 2 sources then use the part # RM-790 that you referenced. If they will only be receiving power from one source you will want to use part # RM-690 instead.
view full answer... - Can Roadmaster Hy-Power Diode # RM-790 be Used in an Outdoor ApplicationThe Roadmaster Hy-Power Diode # RM-790 is sealed so it would be alright to use in an outdoor setting. You wouldn't want to submerge it underwater but it would work just fine if it got some rain or snow on it.
view full answer... - Replacement Diode to Use on a 1999 Jeep Grand CherokeeIf 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.
view full answer... - Running Lights on 2001 Chevy S-10 Not Lighting Up Using Diode Kit for Flat TowingThe first thing you are going to want to check is if running light power is making it all the way back to the diodes installed on your 2001 Chevy S-10. You would do this by connecting the truck to the back of the RV (or other vehicle you are using) and turn the running lights on on the tow vehicle. Then use a circuit tester such as # 40376 if you need one. If there is no power on the input wire from the RV/tow vehicle then the issue is somewhere ahead of the diode. It could just be a...
view full answer...
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