JLUR battery flatlining when flat towing

JJT-NC

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Well, while I agree, one probmem if you have a total disconnect is that your EConnect will also flatline. I just added a #10 wire from the plug to the large battery positive. I also installed a 30 amp diode to keep it one way. Had similar in my Jeep Liberty. That one was SUPPOSED to have it all done by the installer as the brake was electric. They wired the Jeep, but forgot to check the RV! Half way between NJ and Tulsa I started getting warnings, I had one spare day there that I spent chasing down teh parts I needed to install a 12v line in the RV. This time its the reverse! I am going to add a 20 amp fuse in the circuit. No way I should need any more than a trickle charge. But I am wondering, what if I installed a 'brake light kill switch? Break the line on the brake light switch and put a toggle in?? If that is the issue, the Jeep 'wakes up' when the brake switch is activated, maybe that would solve the issue??? Thoughts.
If you want the Connect system to continue to run, then it will eventually run down your battery. In this case, it seems to me that putting a charger on it would be best,





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JimN

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If you want the Connect system to continue to run, then it will eventually run down your battery. In this case, it seems to me that putting a charger on it would be best,
Not sure I understand. I shut the Jeep OFF, nothing should be on when I tow. The Ignition is in the OFF setting. However, apparently the darned thing 'Wakes Up' every time you hit the brakes! This is a drain and over 6 hundred mile two is apparently enough to kill the battery. Perhaps there are other issues that also cause a 'wake up. Anyway, right now I just ran a Charge line with a DIode, I was looking at the RVi toad Charger, but it requires a very expensive monitor to see what it is doing, FIne I suppose if you are also buying their TPMS as it is the same monitor, but no good if you are already covered in that area. If they made it so it would read to Blue Tooth I'd have done it, but apparently they decided to lock up the signal with encryption.I suppose I'll fine out this week. We have a several hour tow. I think I'll grab my meter and check the voltage when we start out and when we arrive, although with the charge line it should be fine and I don't want to take the batteries down again.
 

CoolTech

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JimN,

I think you are spot-on in isolating what the problem is. The JL's enter a sleep-state about 3 minutes after the last door is closed. As mentioned previously, you can easily validate this by closing the driver's door and leaving the window down. After ~3 minutes you can stick a broom handle in through the open window and depress the brake pedal - and NO brake lights SHOULD activate. The Jeep is "asleep" and not drawing any power.

You said that you tried this broomstick test and the brake lights work, even though you let the Jeep sit a few minutes after closing the last door. THIS IS A PROBLEM. Your Jeep HAS to go into a sleep state or it will continue to draw power. I would recommend you to try the broom-stick test again. To be safe, wait 10 minutes after the last door is closed before pressing the brake pedal.

I am biased, but I am not a fan at all of the outdated and old-fashioned, diode-based towed wiring harnesses. I guarantee that all these companies did was to send updated electrical plug configuration specs to their China-based manufacturers and they sent over the same, 20-year old diode-based system design... and crossed their fingers. Not one of them has likely noticed an extra, fault-sense indicator wire in the tail light wiring harness - let alone know what it is for. Duh!

For readers here, the reason is that for the last 20+ years it has been rather easy to detect a bulb-out fault condition with a conventional light bulb. The system simply looks for the resistance across the filament. If this resistance goes to an open circuit condition, then the light is out (filament is broken). This method doesn't work for LED lights. Additional, non-trivial circuitry has been added to detect bulb-out conditions with LED lights. So, when you purchase that 20-year old, diode-based circuitry (albeit with new plugs that fit your Jeep), do you think they are properly isolating the fault-sense circuitry? I'm not saying with any confidence that this is the problem here - but we've heard plenty of strange stories of lights flashing and horns honking when connecting/disconnecting some of these antiquated, diode-based harnesses. In brief, buy the MOPAR harness (they know what they are doing) or buy our harness (complete physical isolation without diodes) and eliminate these possibilities. Sorry, rant over.
 

JimN

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JimN,

I think you are spot-on in isolating what the problem is. The JL's enter a sleep-state about 3 minutes after the last door is closed. As mentioned previously, you can easily validate this by closing the driver's door and leaving the window down. After ~3 minutes you can stick a broom handle in through the open window and depress the brake pedal - and NO brake lights SHOULD activate. The Jeep is "asleep" and not drawing any power.

You said that you tried this broomstick test and the brake lights work, even though you let the Jeep sit a few minutes after closing the last door. THIS IS A PROBLEM. Your Jeep HAS to go into a sleep state or it will continue to draw power. I would recommend you to try the broom-stick test again. To be safe, wait 10 minutes after the last door is closed before pressing the brake pedal.

I am biased, but I am not a fan at all of the outdated and old-fashioned, diode-based towed wiring harnesses. I guarantee that all these companies did was to send updated electrical plug configuration specs to their China-based manufacturers and they sent over the same, 20-year old diode-based system design... and crossed their fingers. Not one of them has likely noticed an extra, fault-sense indicator wire in the tail light wiring harness - let alone know what it is for. Duh!

For readers here, the reason is that for the last 20+ years it has been rather easy to detect a bulb-out fault condition with a conventional light bulb. The system simply looks for the resistance across the filament. If this resistance goes to an open circuit condition, then the light is out (filament is broken). This method doesn't work for LED lights. Additional, non-trivial circuitry has been added to detect bulb-out conditions with LED lights. So, when you purchase that 20-year old, diode-based circuitry (albeit with new plugs that fit your Jeep), do you think they are properly isolating the fault-sense circuitry? I'm not saying with any confidence that this is the problem here - but we've heard plenty of strange stories of lights flashing and horns honking when connecting/disconnecting some of these antiquated, diode-based harnesses. In brief, buy the MOPAR harness (they know what they are doing) or buy our harness (complete physical isolation without diodes) and eliminate these possibilities. Sorry, rant over.
I will give teh test a 10-15 minute try to see if it truly goes to sleep. I am also goiong to hook up my dash cam so I can watch the dash, well actually record the dash ans whatever happens while we are underway. I just did a 4 hour tow, no issues with the charge line installed. The tail lights are sealed LED units so no socket. The diode is SUPPOSED to keep the power from running into the Jeep from the RV. The question is WHY? I towed a number of trips in 2019 and 2020, no issues, just happened this year.
 

JJT-NC

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JimN,

I think you are spot-on in isolating what the problem is. The JL's enter a sleep-state about 3 minutes after the last door is closed. As mentioned previously, you can easily validate this by closing the driver's door and leaving the window down. After ~3 minutes you can stick a broom handle in through the open window and depress the brake pedal - and NO brake lights SHOULD activate. The Jeep is "asleep" and not drawing any power.

You said that you tried this broomstick test and the brake lights work, even though you let the Jeep sit a few minutes after closing the last door. THIS IS A PROBLEM. Your Jeep HAS to go into a sleep state or it will continue to draw power. I would recommend you to try the broom-stick test again. To be safe, wait 10 minutes after the last door is closed before pressing the brake pedal.

I am biased, but I am not a fan at all of the outdated and old-fashioned, diode-based towed wiring harnesses. I guarantee that all these companies did was to send updated electrical plug configuration specs to their China-based manufacturers and they sent over the same, 20-year old diode-based system design... and crossed their fingers. Not one of them has likely noticed an extra, fault-sense indicator wire in the tail light wiring harness - let alone know what it is for. Duh!

For readers here, the reason is that for the last 20+ years it has been rather easy to detect a bulb-out fault condition with a conventional light bulb. The system simply looks for the resistance across the filament. If this resistance goes to an open circuit condition, then the light is out (filament is broken). This method doesn't work for LED lights. Additional, non-trivial circuitry has been added to detect bulb-out conditions with LED lights. So, when you purchase that 20-year old, diode-based circuitry (albeit with new plugs that fit your Jeep), do you think they are properly isolating the fault-sense circuitry? I'm not saying with any confidence that this is the problem here - but we've heard plenty of strange stories of lights flashing and horns honking when connecting/disconnecting some of these antiquated, diode-based harnesses. In brief, buy the MOPAR harness (they know what they are doing) or buy our harness (complete physical isolation without diodes) and eliminate these possibilities. Sorry, rant over.
@CoolTech where can this delay setting be found / changed?
 

CoolTech

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@CoolTech where can this delay setting be found / changed?
I wish I knew. I think most modern cars are now doing something very much like this. I would suspect that the interval to enter sleep state is shorter if you exit the vehicle and use the key fob to lock the doors - a confirmation that you are "leaving".
 

zb39

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I am having the same problem. Just got home today. Dead jeep after 2 days of towing. My braking system is all manual, no electric. I have the Mopar tow harness and they installed it.
I know the push button says OFF when I exit the jeep. I did not have this issue last year. Just started this year. I also have the genesis dual battery system. I can jump the dead battery with the other, but I shouldn't have to. Mine is 2019. My brothers 2020 is doing the same thing. His jeep is bone stock. We have both been flat towing for 30 years, no issues untill now.
 

JimN

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I am having the same problem. Just got home today. Dead jeep after 2 days of towing. My braking system is all manual, no electric. I have the Mopar tow harness and they installed it.
I know the push button says OFF when I exit the jeep. I did not have this issue last year. Just started this year. I also have the genesis dual battery system. I can jump the dead battery with the other, but I shouldn't have to. Mine is 2019. My brothers 2020 is doing the same thing. His jeep is bone stock. We have both been flat towing for 30 years, no issues untill now.
I have ordered the RVi charger. Only doing that because I am concerned about boiling a battery. ALso new or maybe connected issue. The Auto Start/Stop and traction lights come on from time to time. Stop, restart, messages gone. Lights out. Might be weeks before they light again. Sad.
 

JimN

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I have ordered the RVi charger. Only doing that because I am concerned about boiling a battery. ALso new or maybe connected issue. The Auto Start/Stop and traction lights come on from time to time. Stop, restart, messages gone. Lights out. Might be weeks before they light again. Sad.
Update. The RVi Toad Charger has arrived and is installed. We shall see. And on a somewhat related note. I HATE METRIC! Had to go out and buy three different small packs of different size bolts and nuts to get it installed. I THOUGHT I bought an American Icon here! If I wanted Metric I'd buy a foreign car! And yes I know much of what is built here is sourced offshore and also things built here are sold offshore, but let the world change to match us! When the SHTF, they will all come running to us!
 

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