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Tow Ready Battery Isolation Solenoid

Tow Ready Battery Isolation Solenoid

Item # TR118665

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Tow Ready Battery Boxes - TR118665
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  • Battery Boxes
  • Switches and Solenoids
  • Tow Ready
This battery isolation solenoid shuts off the 12-volt feed from your vehicle battery to 12-volt accessories on your trailer when the ignition is turned off. This lets you run the trailer's electrical components without draining your battery. Call 800-298-8924 to order Tow Ready accessories and parts part number TR118665 or order online at etrailer.com. Free expert support on all Tow Ready products. Guaranteed Lowest Price and Fastest Shipping for Tow Ready Battery Isolation Solenoid. Accessories and Parts reviews from real customers.


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Tow Ready Accessories and Parts - TR118665

This battery isolation solenoid shuts off the 12-volt feed from your vehicle battery to 12-volt accessories on your trailer when the ignition is turned off. This lets you run the trailer's electrical components without draining your battery.


Features:

  • Hard-wired, 3-pole solenoid switches off your vehicle battery's 12-volt feed when the ignition is turned off
    • Allows you to use battery-powered electrical components on your trailer without draining your vehicle's battery
    • Grounds on your vehicle's chassis
  • Rated for 80 amps
  • 1-Year limited warranty


118665 Tow Ready Battery Isolation Solenoid







Video of Tow Ready Battery Isolation Solenoid


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




Video Transcript for Tow Ready Battery Boxes TR118665 Review

Today we're going to review part number TR118665. This is the Tow Ready Battery Isolation Solenoid. Now this battery isolation solenoid will shut off your 12-volt feed from your vehicles battery to your 12-volt accessories on your trailer when your ignition is turned off. This will allow you to use battery powered electrical components on your trailer without draining your vehicles battery. Now, when you do install this, the mounting bracket right here is the ground. This does need to ground to a good clean metal surface. This solenoid is rated for 80amps.

The wire we recommend when attaching wires to this is usually 10 to 12 gauge size. Now, when you do install this, basically like I mentioned, this has to be mounted into a good clean metal surface to get to ground. Right over here, this would be your voltage that would come in from your battery. Over here would be your voltage that's going out to your trailer connector. This connection right here to the ignition switch power source. That's should do it for the review on part number TR118665.

The Tow Ready Battery Isolation Solenoid. .


Customer Reviews

Tow Ready Battery Isolation Solenoid - TR118665

Average Customer Rating:  4.7 out of 5 stars   (47 Customer Reviews)

This battery isolation solenoid shuts off the 12-volt feed from your vehicle battery to 12-volt accessories on your trailer when the ignition is turned off. This lets you run the trailer's electrical components without draining your battery.

- TR118665
by:

The item was as described. The directions were very accurate and installation was easy. Will be back for any other needs. 13770



- TR118665
by:

Kit was sufficient to completely wire my 66 F100 for Electric brakes. I wrapped all wires under the hood with black tape and used original harness clips below the hood to cowl seal for a " factory harness" look. Truck is almost all original and a bit rusty but it's mine.. I wired an etrailer solenoid in line to trailer power, it is energized by the ignition and I added an led toggle switch under the dash to interrupt that circuit of needed. All the parts arrived in great condition and on time. 401783



- TR118665
by:

Used this isolate trailer battery from car battery. This is third one I've installed and it works great. Learned something this time to clean up the wiring install. Window washer wire was right next to battery where this was installed so used that wire to hot it up when ignition is on. 359994



- TR118665
by:

NO INSTALLATION INSTRUCTIONS included as promised!!! I was told when I ordered that printed wiring diagram would be included in package. No instructions were included with the product or on package. Had to call CS and go online to find them. Not too tough but needed clarification on which post was power in and which is power out. Just frustrating being told one thing at time of order and not receiving as promised. Product works as intended. 130589



- TR118665
by:

The product is great but customer service is awful. I ordered this along with two other items and after a week of not receiving the items, I had to call to find out where my stuff was to find out that they had not been sent out. I cancelled one item and finally received my other products almost two weeks later. Buy from the other guys if you can find what you want. Shipping in two days! 406846



- TR118665
by:

Had to change my order after submitted on the web and that was done quickly with help from a great customer service rep. Received the order quickly and all parts were as expected. Love the online video provided by etrailer in helping to chose the right product and installing it, it is hard to improve on perfect. 211298



- TR118665
by:

After being energized 2 or 3 times this solenoid failed to open the circuit when denergized. After being tapped on multiple times with a screwdiver handle, it finally opened the circuit. The load was only what my Tekonsha Primus IQ brake controller with no trailer connected. Have not checked it since the van this was installed in has been laid up for winter. 355677


Comments

The faulty solenoid was replaced. Upon installation everything now functions properly. Customer service was most helpful and quick to solve this issue!

Tony B - 04/23/2018

37517

- TR118665
by:

It works, guess that means I hooked it up right! Not a lot of room to work with in the 2013 Honda Odyssey but turned out good. Should have moved it a little farther forward away from the air box and drilled 2 holes but I had a space to slide the left tab in and saved a hole. Yes it is very tight and grounded good. Going on a long road trip and now we'll have piece of mind knowing we wont be stranded out in the middle of nowhere for forgetting to unhook the trailer connector. 121803


Comments

Good looking installation. I am doing same on my 2014 Odyssey. I have not located a good place to connect my control wire to enable the relay only when ignition is on. Please suggest a location. Thanks in advance!

-- comment by: MikeE - 11/29/2014

7840

Things like vehicle radio and antenna motors for powered antenna are ideal for installing the relay in line. Either in your owners manual or on the fuse box itself, it should state which items are on while the ignition is on. You might consider using a fuse tap, which is a fuse you can attach a wire to and provides the 12 volts needed. Take a look at # F2526
Firestone Fuse Circuit Tap Kit
$16.71
.

-- Rachael H - 12/1/2014

Comments

Still working like new 1 year later. No problems at all so far.

Gerald M - 03/23/2015

10242

- TR118665
by:

My camper stopped charging the coach battery. Tested an found the isolator wasn't passing power thru. Searched online and this was the least expensive (by far in some the cases). Quick shipping, easy install and charging again. I am a happy camper! Thanks! 560213



- TR118665
by:

There were a lot of different isolation solenoids to choose ftom. This was perfect for my small utility trailer. Delivery was scary fast. 477684



- TR118665
by:

My truck came with only a four pin trailer connector. I installed a seven pin connector received from etrailer and realized I needed to prevent battery drainage on my truck caused by the trailer battery charging when the truck engine wasn't running. The battery isolation solenoid provided a perfect solution. Great product at reasonable price. As usual etrailer exceeded my expectations with next day delivery. 522664



- TR118665
by:

It's a relay/solenoid! Works great so far. We got this to wire our small teardrop for underway charging. I found an ignition-switched voltage source in the engine bay, and now I don't have to think about whether or not I've unplugged the trailer. Would use again. 442297



- TR118665
by:

This is being used as a battery isolater in a 2006 Class C RV, replacing a failed Motorcraft part. It worked after installation, we’ll see how long it lasts! Only complaint is that the terminals for the battery connections partially obstruct the mounting flange making it a little difficult to install, especially when there is not a lot of room to work. 543530



- TR118665
by:

Very happy with product construction didnt get to install it yet since it has been raining everyday since I recieved it,shipping was fast and overall experiance with etrailer was very good and I will be buying more from them and will definitely recommend to others 200192



- TR118665
by:

The product was exactly what I wanted for the amount I was told it should cost. I wish there would have been instructions there just to make double sure I know what I'm doing but it's easy to find it online. 329768


Comments

Ive been remiss at installing it. I think I know what to do now but Im still somewhat unsure. Again, the directions would have been easier to do if there were a bit more there.

Kelly H - 01/04/2018

32570

- TR118665
by:

it's a simple part that just works as designed. Once installed it's good to know your trailer Isn't draining your car's battery when shut off you car and park overnight or out to dinner or lunch with the trailer cord connected. Much less likely to have any battery issues or forget to replug in the trailer and drive off and have no trailer lights working. 310521



- TR118665
by:

Works... instructions not included 440111


Comments

Works

Steven L - 10/06/2018

44370

- TR118665
by:

This is my third order this year. Every order on time. Great quality,fair price,love the how to videos . 640588



- TR118665
by:

Works well. I wish it was a bit smaller but it is high amperage. 639009



- TR118665
by:

excellent business to to work with 633173



- TR118665
by:

Good quality, continuous duty, perfect fit. Using as battery switch between start and house batteries on my boat. Flip a switch and go, no longer have to get up and go to the stern and crank a manual switch on a bouncing boat in rough water. 608191



- TR118665
by:

Does exactly what I needed; prevents the trailer from discharging the tow vehicle battery when ignition is turned off. 607586



- TR118665
by:

Exactly what I was looking for. Works well so far. 604520



- TR118665
by:

only complaint is that no instructions came with this part. 584373


Comments

The product description overview video linked above will actually run you through how to wire the solenoid. The terminal on either side is used for the incoming and outgoing power it doesnt matter which terminal is used for which and the center terminal is used to an ignition switched circuit. The radio circuit is frequently used, because it powers down when the ignition is off.

-- Mike L - 11/21/2018

45921

- TR118665
by:

Received the solenoid and installed the same day. No more disconnecting the trailer plug over night and forgetting to reconnect in morning. Etrailer delivers!! 583740



- TR118665
by:

JUST WHAT I ORDERED AND SHIPPED VERY PR OMPTLY. 581196



- TR118665
by:

delivery was so fast the product was great and shipping was really less than all the others, thank you for being concerned for the buyer and not just to make all the money you can - like some of the others. 567654



- TR118665
by:

Just what we wanted for rebuild. Looks great, good function 559439



- TR118665
by:

just what I was looking for 470236



- TR118665
by:

Works exactly like I wanted, this should be part of any trailer wiring kit 459662



- TR118665
by:

Working well 446945



- TR118665
by:

This is just the product that we wanted at the right price. 409676



- TR118665
by:

It looks exactly like the picture I have not hooked it up yet but I'm sure it will work fine. Shipment was fast and accurate. 372784



- TR118665
by:

This simple device save the worry of forgetting to disconnecting the car from the trailer and the hassle of a dead battery when you do. 364573



- TR118665
by:

Works as stated and no problems 343629



- TR118665
by:

Works great in the circuit I installed in my truck to charge my trailer battery while driving. Etrailer is my go to for my rv needs. Great prices and fast shipping are the norm. 332554



- TR118665
by:

excellent product, sturdy and well built... order was delivery exceptionally fast too!! 305471



- TR118665
by:

Great product. Great company to work with. Excellent customer service! 302281



- TR118665
by:

I had a problem with install due to my own fault. Etrailer was very helpful. I got excellent service.. 285961



- TR118665
by:

Easy to order, fast shipping. 276421



- TR118665
by:

Great product and fast delivery. 241180



- TR118665
by:

looks good and good price 188882



- TR118665
by:

Great service from ETrailer, as always. I don't like my 7pin "hot" when I'm parked. This solenoid does the trick. 111356



- TR118665
by:

Good customer service, prompt shipping 108858



- TR118665
by:

Perfect replacement. Works great. 107987



- TR118665
by:

just what I wanted. Excellent customer service too. 62725



- TR118665
by:

Very high quality and works perfect. 58093


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Ask the Experts about this Tow Ready Accessories and Parts
Do you have a question about this Accessories and Part?


  • Installing a Towed Vehicle Battery Switched Charging Line on 2016 Ford F53 Chassis Motorhome
  • For your 2016 Coachmen Mirada 35LS, to find a switched power line I recommend using a circuit tester like # 40376. Then you will use the Roadmaster Battery Charge Line Kit for Motorhomes # RM-156-75 with solenoid # TR118665 after the circuit breaker with the center post connected to your switched power line. This with make sure that power is only drawn from the motorhome when the ignition switch of your Coachmen is turned on. Then on the towed vehicle (toad) side you can use the Roadmaster...
    view full answer...

  • Recommendation for Charging a Lithium Battery Bank From a 2009 Ram 3500 Diesel Tow Vehicle
  • The Tow Ready Battery Isolation Solenoid # TR118665 along with 00 gauge wire and Pollak Single-Pole, Round Pin Trailer Wiring Socket # PK11851 along with # PK11852 will allow you a great connection for charging your battery. I also recommend putting a 40 amp circuit breaker # 9510 in line to protect your system. The issue is it will not amplify your charge so you will still be limited to the 2-3 amps charging above what your truck uses from your alternator. For a better option, I recommend...
    view full answer...

  • Can 7-Way Junction Box 277-000141 Be Used to Charge Trailer Battery
  • If there happened to be a 12 volt keyed power source in the circuits of the # 277-000141 you could use it for the isolation solenoid # TR118665. Essentially you would need to have the 12 volt circuit of the vehicle already be only active when the key is on. Which if that were the case you wouldn't need the solenoid realistically. If the 12 volt circuit of your truck's 7-way is active all the time you would need to install the solenoid on that circuit and that would get the circuit active...
    view full answer...

  • Installing DC Power And Power Inverter To Cargo Trailer
  • For DC electricity, I can help you out. You can run a 10 gauge wire like # 10-1-1 sold by the foot from a 6-way or 7-way connection from the 12V to a deep cycle 12V battery and then run the battery to a ground on the trailer. You can use a solenoid like # TR118665 in your tow vehicle if you want to ensure you don't drain the vehicle battery when your truck isn't running. This will isolate the deep cycle 12V trailer battery. To charge your battery, you can use a CTEK D250S DUAL Universal...
    view full answer...

  • Isolating Auxiliary Battery From Draining Break Away Battery
  • You can isolate the break away battery from the auxiliary battery using the Tow Ready Battery Isolation Solenoid # TR118665. The auxiliary power supply that is needed on this solenoid can be the running lights of your trailer. That way, when your trailer is connected, you can charge the break away and the auxiliary trailer battery, but when not connected the break away battery will not be drained by the auxiliary trailer battery. So the 12V comes into the trailer and runs to the aux...
    view full answer...

  • Installing A Solenoid For Second Battery In Truck
  • When using the TorkLift HiddenPower Under-Vehicle Battery Mount with Battery Box # TLA7728 you mentioned, you can use a solenoid like the Starter Solenoid - SPST - 12 Volt - 100 Amp - Continuous Duty - Insulated - UL Listed # PK5230701 or Tow Ready battery Isolation Solenoid # TR118665. This solenoid allows the vehicle battery to send power to the second battery when the vehicle is in accessory mode or when the vehicle is running. It will not draw power from the battery when the accessory...
    view full answer...

  • 12 Volt Pin on Aftermarket 7-Way on a 2000 Toyota Tacoma is Hot All the Time
  • On some vehicles, the 12 volt circuit is hot all the time. Since you hardwired in the # ETBC7, it is directly connected to the battery via a 40 amp circuit breaker so it should be hot all the time. This is nothing to be concerned about unless something is plugged in and drawing power. Just remember that if you will be parked for a long time, disconnect the trailer! If there is nothing on the trailer that uses the 12 volt pin then you will not have to disconnect the trailer. Even though...
    view full answer...

  • How To Prevent Tow Vehicle Battery From Draining Trailer Battery
  • As you mentioned, this is normally the accessory battery draining the starting battery (tow vehicle) and most of our products like the Tow Ready Battery Isolation Solenoid, Item # TR118665, are focused on preventing this situation. It is possible to set this up in reverse but we do not have much experience with it or customer feedback about it. The best solution for preventing your tow vehicle from draining your trailer battery is to have the same type of batteries. In a multi-battery...
    view full answer...

  • What is Amp Draw Rating for Tow Ready Battery Isolation Solenoid # TR118665
  • The Tow Ready Battery Isolation Solenoid # TR118665 that you referenced is rated for up to 80 amps.
    view full answer...

  • Installing Tow Ready Battery Isolation Solenoid Downstream from Trailer Connector
  • You can convert your trailer connector and mount the Tow Ready Battery Isolation Solenoid # TR118665 downstream from the plug. One place the ignition power post could be connected to is your trailer's running lights. If you tie in the ignition switched power post into the running lights, then your running lights will need to be on for your battery to charge. I called Tow Ready to double check, and they verified there would be no issue to mount the solenoid on the trailer and tie into the...
    view full answer...

  • 2010 Toyota Highlander Hybrid 7-Way Trailer Connector for Charging Trailer Battery
  • Since you need to charge a trailer battery you are correct that you need to install a 7-way at the rear of your 2010 Toyota Highlander. Since you have the correct connector for the part # 56042 to install you will need to use it as the base for your wiring. From there you will adapt it to a 7-way with the part # 37185. You will plug the 4-ways in together and then to complete the charge wire you would need to run the black wire of the adapter up to the positive post of the vehicle battery...
    view full answer...

  • Powering Interior Trailer Lights With AC Power
  • I do have a couple of solutions for you to power your trailer lights with AC power but I do not have a way to plug the whole 7-way into a wall outlet. However, there are two ways you can wire the lights to a trailer battery and successfully power them with AC power. The first way is wiring the lights to a trailer battery that is wired to a converter part # PD9130LV. You can use part # 10-2-1 to wire the converter to the battery. The other side of the converter then wires to a 30 amp...
    view full answer...

  • Fuse Tap Recommendation for 2016 Toyota Highlander to Use Isolation Solenoid TR118665
  • We have the fuse tap kit part # F2526 which you could use to tap into the inverter fuse of your 2016 Toyota Highlander to use as the activation circuit of the Isolation Solenoid part # TR118665. Any other fuse that only sees voltage when the key is on would work well too.
    view full answer...


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