Tow Ready Battery Isolation Solenoid
(69 reviews)
Price: $29.10
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Tow Ready Battery Isolation Solenoid
Item # TR118665
Retail:$45.67
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Tow Ready Accessories and Parts - TR118665
- 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.
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 Satisfaction Score:
98% were satisfied with this product
2% of customers were not satisfied
- Wrong item was ordered
- Did not fit
- Received too many
Customer Reviews
Tow Ready Battery Isolation Solenoid - TR118665
Average Customer Rating: 4.7 out of 5 stars (69 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.by: Gerald M.03/23/2014
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.
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
Still working like new 1 year later. No problems at all so far.
Gerald M - 03/23/2015by: Bill M07/19/2018
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.
by: Dan G02/21/2020
Purchased this to keep my starter from potentially pulling from my trailer battery on startup. This diode (part#: RM-690) would probably have done that job just as good, if not better, but wouldn't keep the trailer plug from having live power all of the time. I did install this solenoid, though, and it's actuated by my car's 12v accessory power (on only when car is on or in accessory mode - not during ignition). Additionally, I added a rocker switch to my cars interior, right under my brake controller, so I can turn the solenoid off completely when I'm not towing. I figured this would lengthen the solenoids life, and add to my peace of mind knowing that my trailer plug doesn't have a direct line to my vehicle's battery all the time.
The solenoid itself is a little larger than I had expected, but it's been great to have so far. I'd recommend this product.
Comments
Still working well.
Dan G - 02/22/2021by: Allen 09/18/2021
Installed this on my 2013 Chev 2500HD to disconnect truck battery from slide in camper batteries when ignition is off. Chevrolet did not provide this in their stock manufacturing. Eliminates the chance of running down the truck battery when dry camping.
by: Tony B.03/19/2017
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.
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 - 04/23/2018by: Timothy08/31/2018
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!
Comments
One year later - working beautifully !
Timothy - 09/04/2019by: Terry B.06/27/2017
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.
by: Bob03/15/2022
Good, fast, reliable service!
by: Michael02/15/2022
works like it should missing one nut had to go by one
Comments
I will have our customer service team reach out to you.
-- 
Jenny N - 02/20/2022by: Steve B10/25/2016
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.
by: Eric 10/10/2019
Replacing the battery isolator seems to have solved a number of electrical issues in my 30 year old RV. Now the engine will recharge the house battery again even though solar still does most of the work. New isolator takes a a smaller draw off the wiper circuit which also powers the cruise control. Now cruise doesn't disconnect when the wipers are turned on. Only one problem in installing. Original had slots in the mounting bracket. Replacement has holes. Both mounting screws had to be completely removed. One was quite awkward to get to. Installing could have taken 5 minutes, but because of that second screw stretched out to maybe 20 minutes.
by: Michael05/06/2019
Works well. I wish it was a bit smaller but it is high amperage.
by: tim p09/05/2019
the battery isolater solenoid works perfect when wired correctly when protecting my truck battery from my trailer winch battery when the winch is in use I highly recommend this product.
by: Gregg K03/29/2017
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.
by: Whitney T10/13/2017
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.
by: John06/16/2018
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.
by: Thomas 07/24/2021
Used to isolate my wench, from the truck battery, when in use. Then I can connect back to charge both batteries while driving and wench is idol. delivery was fast through USPS.
by: Carl01/14/2017
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.
by: Kelly H01/04/2017
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.
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 - 01/04/2018by: Mike02/23/2019
Does exactly what I needed; prevents the trailer from discharging the tow vehicle battery when ignition is turned off.
by: JR09/14/2020
Would love to see a wiring diagram or instructions/video for install on etrailer. Otherwise good part.
by: KR05/14/2014
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.
by: Rocky Y07/13/2015
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.
by: Ronald06/01/2020
Big, strong and versitle. Battery will power Brakes, power lift , winch and breakaway.
by: Rob K06/03/2015
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
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See what our Experts say about this Tow Ready Accessories and Parts
- Does Center Pin of the Tow Ready Isolation Solenoid TR118665 Need a FuseYou would not need to fuse the circuit that powers the center pin of the part # TR118665. This only draws 1/2 an amp and does not power anything so circuit protection would not be needed. It's only function is to close the circuit to let the voltage pass through the other two pins.
view full answer... - Can Either Pole of the Tow Ready Battery Isolation Solenoid be Used as Input/OutputEither side of the Tow Ready Battery Isolation Solenoid part # TR118665 can be used as the input or the output. I confirmed this with my contact at Tow Ready.
view full answer... - Does Tow Ready Battery Isolation Solenoid Draw AmperageThe Tow Ready Battery Isolation Solenoid Item # TR118665 that you referenced does not actually draw any amperage worth noting when used. To activate it only take a few milliamps and it does not rob amperage that runs through it on the power pins so you'd be fine using it with a 20 amp circuit.
view full answer... - How to Charge a Breakaway Battery on a 2011 GMC SierraThe 12 volt power on the 7-way is usually rated at 40 amps like you mentioned but it is not always a keyed source. It may or may not turn off when the ignition is off, it just depends on how it is ran. However, if you splice the breakaway battery charge line into the trailer side of the 7-way then the power would stop if the trailer plug is disconnected for the vehicle. In regards to the daytime running light (DRL) circuit, you can use this for the on/off key but I don't recommend pulling...
view full answer... - Can Tow Ready Battery Isolation Solenoid # TR118665 Install on HorizontallyThe Tow Ready Battery Isolation Solenoid # TR118665 that you referenced does not have to be installed in any particular orientation. It can lay flat or on it's side if needed and still function properly.
view full answer... - Can Trailer Battery be Overcharged by 12V Feed From 7-Way ConnectorThe 12V feed from your tow vehicle's 7-Way connector carries enough current to maintain a charge on your trailer mounted battery, but it does not have enough to actually charge up a depleted battery. Since the battery will really only get a trickle-type charge from the 7-Way, you do not need to worry about it being overcharged during a long drive. Adding a battery isolation solenoid like the Tow Ready # TR118665 that you referenced is used to prevent the trailer battery from draining the...
view full answer...
- How Does Isolation Solenoid Wire to Activate 12 Volt Power Circuit Only When Key is OnWhat you need is the isolation solenoid part # TR118665. It is pretty easy to wire up too. Basically the outside posts get wired inline with your 12 volt power circuit feeding your 7-way and then the center post runs to a power source that only sees voltage when the key is on. Typical circuits are ignition or radio. I attached a picture that shows how it wires as well.
view full answer...
- Can Battery Isolation Solenoid TR118665 be Used on 2016 Nissan FrontierThe battery isolation solenoid part # TR118665 can be installed on your 2016 Nissan Frontier to allow you to only activate your 12 volt power circuit when the key is on. For the center pin of the solenoid you have to find a circuit that only sees power when the the key is. Typically people run a wire up to the fuse box looking for a circuit labeled ignition. Or if you can find a circuit that only sees power when the key is on like the radio that can work too. In my car I have a couple...
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- What Ignition Power Source Can I Use on a 2013 Toyota Highlander With Part # TR118665The ignition source is a signal used to tell the Tow Ready Battery Isolation Solenoid part # TR118665 to turn off/on. You can use any power source on the vehicle that only receives power when the vehicle is on such as the radio. The radio fuse is located in the engine compartment fuse box. It is a 20 amp fuse in the number 26 position. I have attached a photo of this location for you.
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- Pin Functions on the Tow Ready Battery Isolation Solenoid # TR118665The 2 pins on the side of the Tow Ready Battery Isolation Solenoid # TR118665 are the input/output of the 12V power (it doesn't matter which is which) while the center pin is supposed to be connected to your ignition switch. I have attached a photo and review video to demonstrate. Another thing you will need to note is that your 12V power pin and trailer brakes/brake controller signal are on 2 different pins (see attached picture of typical 7-Way wiring) unless you are referring to your...
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- Battery Isolation Solenoid Recommendation for 2014 Volvo XC90Sounds like you are looking for a way to prevent your trailer battery from draining your Volvo battery when the engine isn't running. For that we have the Tow Ready solenoid part # TR118665. You'd need to install this inline with the 12 volt accessory circuit of your trailer wiring. The center pin gets wired to a circuit that only sees voltage when the vehicle is on and you'd be set. The circuit would prevent the battery from being able to drain the other.
view full answer... - What is Amp Draw Rating for Tow Ready Battery Isolation Solenoid # TR118665The Tow Ready Battery Isolation Solenoid # TR118665 that you referenced is rated for up to 80 amps.
view full answer... - How To Charge Auxiliary Battery On Trailer Only When 2018 Audi Q7 Ignition Is OnBased on your information, I believe your best option is to add a solenoid like the Tow Ready Battery Isolation Solenoid, Item # TR118665. This solenoid will shut off the 12-volt feed from your vehicle battery to the 12-volt accessories/auxiliary battery on your trailer when the ignition is turned off. This auxiliary power wire will connect to the 12-volt power pin on a 7-Way connector (see attached picture). I am also attaching a help article and video for you to check out.
view full answer...
- How To Prevent Tow Vehicle Battery From Draining Trailer BatteryAs 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... - Using Battery Isolating Solenoid # TR118665 to Switch off 7-Way Accessory Power FeedYou can install a battery isolating solenoid like part # TR118665. The solenoid would be wired according to the photo I edited for you. When the center pin of the isolator is wired to an ignition powered power source (a circuit that only has power when the ignition switch is turned on), the power feed will only be active when the ignition is turned on. IF wired correctly, the solenoid will automatically power the circuit up when the ignition is switched on. This is not a vehicle specific...
view full answer...
- Does Isolation Solenoid # TR118665 Have to Mount in a Specific OrientationThe isolation solenoid part # TR118665 that you referenced does not have to mount in any particular orientation to work properly. Basically it only needs to be wired up properly and it's good to go. The positions of the solenoid in our pictures are not based on how it has to install.
view full answer... - Solution for LED Taillights that Stay Partially Illuminated When Circuit is OffLED lights can partially illuminate with even the tiniest amount of amperage. What you described isn't super common but we hear about it pretty frequently. What you can use though is the isolation solenoid part # TR118665 which you'd wire in line with the circuit that stays active and then run the center pin to the same circuit on your Dodge. This allows the circuit to be totally dead when not in use.
view full answer... - Troubleshooting Continuous 12 Volt Power to Trailer Connection on 2002 Ford F-350It sounds like you don't like the 12V power to your trailer plug when your key is off because of the possibility of draining your truck battery and leaving you stranded. To fix that issue, the Tow Ready Battery Isolation Solenoid # TR118665 can be used so power can only be drawn at your 7-way when the truck ACC is on at your ignition. This solenoid has a middle terminal that requires a feed from your switch to allow power through and the unit's mounting flange is actually the ground connection...
view full answer... - Installing A Battery Isolator On The Trailer Side Of The Wiring ConnectionI'm happy to help with that isolator and wiring. I checked your invoice and see you went with the Tow Ready Battery Isolation Solenoid # TR118665. This is a good choice and will need to be mounted to the frame because it uses the mounting holes for ground. Make sure you have a clean area with a metal to metal connection for that mount. From your 7-way, you will run the 12V power wire to the left terminal when facing the 3 pins, the 12V accesory terminal in the middle will go to your...
view full answer...
- How to Install Tow Ready Battery Isolation Solenoid TR118665 to Protect Vehicle BatteryThe Tow Ready battery isolation solenoid # TR118665 allows controlling the flow of 12V power by switching on and off (closing and opening) based on the presence of a 12V trigger signal at its center terminal. When this terminal receives power this closes the solenoid which makes the connection from the left-hand input terminal through to the right-hand output terminal. The solenoid will pass the 12V signal ONLY when there is a triggering signal sent to its center terminal. This provides...
view full answer... - Battery Isolation Solenoid for 7-Way of 2012 Ram 2500 to Turn Off 12 Volt Accessory CircuitSounds like you are talking about the 12 volt accessory circuit of a 7-way trailer connector. For some vehicles with factory 7-ways the circuit is only active when the key is on. Most however are on all the time. If the 7-way was hardwired to the vehicle then it will be on all the time unless an isolation solenoid was installed like part # TR118665. Basically this gets wired inline with the circuit and the center pin, when wired to a power source that is only active when the key is on,...
view full answer...
- Where Does Blue Terminal of Install Pic for Isolation Solenoid TR118665 RunSounds like you are talking about the picture of the Tow Ready Battery Isolation Solenoid # TR118665 which I attached. The blue side of the solenoid is to be ran to the 12 volt accessory circuit of your 7-way which is the 1:00 pin.
view full answer...
- Will a 130 Amp Alternator Cause Problems with 80 Amp Rating of Tow Ready Battery Isolation SolenoidAs long as you install the Battery Isolation Solenoid, # TR118665, correctly (see photo) and the items you are powering on the battery isolator output circuit does not draw more than 80 amps you will not have any problems. In most cases the battery isolator is installed on the charge line going to a trailer connector at the back of a vehicle and this circuit is used to maintain the trailer batteries charge and/or power utility lights in or on the trailer. In this situation your alternators...
view full answer...
- Is a Battery Isolator Needed When Using 7-Way Connector To Charge the Trailer BatteryYou will need a battery isolator, like Tow Ready Battery Isolation Solenoid, part # TR118665, if you plan on leaving the trailer connected to the truck when the truck is off. If you unplug the 7-Way, the trailer battery cannot drain the truck battery. If you leave them connected, you would need an isolator to keep the trailer from drawing down the truck battery. The isolation solenoid has three connections. If you are looking at the unit with the dome facing up and the 12v sticker right...
view full answer...
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