JLUR battery flatlining when flat towing

Onthego

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I'm towing my JLUR behind a 35' gas-powered Class A. I'm using a Blue Ox baseplate, tow bar and umbilical but a Roadmaster Invisibrake. I also use the additional Roadmaster wiring kit that illuminates a red light RMI on my dash when I press the brake on the motorhome to indicate that the Jeep brakes are also being applied. The Jeep has Push-to-Start and automatic transmission.

Three times last summer the Jeep battery was drained when I drove the motorhome for more than one day without unhooking and driving the Jeep. At first, I thought I might have left the ignition in ACC, and it was a user error. After the second time, I made a point of starting the Jeep and letting it idle for 5 minutes before towing it each day, but the battery died again after towing it four days in a row.

Roadmaster says they have another wiring kit I can buy to provide a trickle charge to the Jeep when I'm driving, but they said I needed to disconnect it when I'm parked overnight or it might drain the motorhome battery! Another RV owner suggested a solar charger to provide the trickle charge.

Does anyone have any thoughts or suggestions? I'd like an idiot-proof way to make sure the Jeep battery stays charged and I don't need to do anything special when I'm towing multiple days. In your response, please keep in mind that I know more about how the systems work in my motorhome than I do about how a car works under the hood!





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grady2hig

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Why do you need the Jeep on to tow it? Can you just find some brake likes that attach to the back and just not wire anything to the Jeep itself?
 

OrangeWave

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Why do you need the Jeep on to tow it? Can you just find some brake likes that attach to the back and just not wire anything to the Jeep itself?
You need some sort of powered supplemental brake system to activate the brakes on the towed vehicle. I assume this is what is draining the battery. I'm about to set mine up for flat tow and bought the CoolTech deluxe kit that included the cable to charge the JLUR battery from the coach.
 
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Onthego

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Why do you need the Jeep on to tow it? Can you just find some brake likes that attach to the back and just not wire anything to the Jeep itself?
I rarely see a towed Jeep with auxiliary lights on the back. It's definitely an option. Thanks for your input!
 
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Onthego

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You need some sort of powered supplemental brake system to activate the brakes on the towed vehicle. I assume this is what is draining the battery. I'm about to set mine up for flat tow and bought the CoolTech deluxe kit that included the cable to charge the JLUR battery from the coach.
I already have a lot of the components of the CootTech Deluxe kit.

I just found the RVi Towed Battery Charger online for $55. I already have the umbilical they suggest using, so I'm leaning toward that one.

I appreciate your input!
 

Jmonroe

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I use the RVI toad charger. 10 minute install. No more dead battery
 

zjaw

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I Tow mine a lot. Over 7000 miles on this jeep. I had them run a charge line on mine. But I do not unhook it when we stop if we are back on the road the next day. Do you cut the Jeep off when towing? I do unplug my brake buddy sometimes when I stop. But have forgot before and didn't cause any problems
 

Jmonroe

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The RVI "toad brake" mentioned earlier has a "brain" that will monitor charge level.
 

RubiJR

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I've heard of the manual cable that routes into the Jeep and then what looks like a metal piece clamps to the brake pedal. Is that not a good option? Or is it better to go with wiring to the Jeep so you get the lights working with the RV? I haven't decided which route to go but I do kind of like the Jeep lights and RV lights synchronized. Suggestions appreciated
 

Jmonroe

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I've heard of the manual cable that routes into the Jeep and then what looks like a metal piece clamps to the brake pedal. Is that not a good option? Or is it better to go with wiring to the Jeep so you get the lights working with the RV? I haven't decided which route to go but I do kind of like the Jeep lights and RV lights synchronized. Suggestions appreciated
Your brake lights will work anytime the brakes are applied, regardless of which suplimental system you use. We've been using the SMI Airforce One system for years and yes, it does use a cable attached to the brake pedal, pulled by a cylinder mounted under the dash. In a typical installation you won't see any of it unless you lay on the floor and look up.

You need a special harness (or supplimental sockets) to have working tail lights and signal lights. This will activate whenever you use either of these features on your coach.
 

wolfdog

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Someone mentioned about the JL with Stop/Start has two batteries, this certainly could effect separate chargers I bet? I have no RV experience but do know this "two battery" is going to be a problem for all of us...wanna bet?? lol

Funny our 2015 Cherokee Trailhawk has Stop/Start with one large battery and the S/S works smoother and faster than our JLU??? The battery however is really expensive to replace!

Go Jeep!!!
 

twisty

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Someone mentioned about the JL with Stop/Start has two batteries, this certainly could effect separate chargers I bet? I have no RV experience but do know this "two battery" is going to be a problem for all of us...wanna bet?? lol

Funny our 2015 Cherokee Trailhawk has Stop/Start with one large battery and the S/S works smoother and faster than our JLU??? The battery however is really expensive to replace!

Go Jeep!!!
No the info I recall is the starter battery lead goes to the big battery so that one charger should do both. What seems to be a bigger problem is jump starting. It seems you need to keep the jumper cables on for a bit before it will start. The is the latest info I have heard.
 

wolfdog

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I think there are some threads on this forum here, I also believe some stuff on you tube about it.

My opinion is that Jeep made a big bob boo using this two battery set up setup, kinda complicated, why? Trying to figure which one is bad, changing out etc. I am not a great one to talk electrical, just saying!

As said before, our Trailhawk has one battery, works super! I do understand however that replacement batteries cost $180 to $250, so...??

Hope someone on forum has a solution for Onthego??
 
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Onthego

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I think there are some threads on this forum here, I also believe some stuff on you tube about it.

My opinion is that Jeep made a big bob boo using this two battery set up setup, kinda complicated, why? Trying to figure which one is bad, changing out etc. I am not a great one to talk electrical, just saying!

As said before, our Trailhawk has one battery, works super! I do understand however that replacement batteries cost $180 to $250, so...??

Hope someone on forum has a solution for Onthego??
Thanks for the discussion. I had the RVi Towed Vehicle Charger installed earlier this week. I'm heading out on an RV trip on Monday and will be towing the Jeep for three days straight until I get to my destination on Wednesday, the Albuquerque Balloon Fiesta. Since it is a big city and I can get AAA to come charge the Jeep battery if it's dead when I arrive, I plan to set the transfer case to Neutral, the gear shift to Park (as I've been doing all summer) and see if the new RVi Charger does what it's supposed to do without any intervention from me (no disconnecting the umbilical, no starting the Jeep each day to let the engine idle, etc).

For the response that hinted about disconnecting the wire around the brake, that's not what I want to do. The whole idea is that I hoop up the Jeep, drive the RV for one or more days, then disconnect the Jeep and have it start. If you haven't driven an RV, there are a lot of details to manage. I don't want to add any more details for the Jeep.

The RVi charger was wired into the socket for the umbilical that I already use, so there isn't anything additional for me to do. I hope!
 

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