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Rear cargo 12V oulet usage/battery recharging

ipizzaipizza

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Does the 12V battery automatically get top off from the main pack battery when it hits a certain voltage? Question is in regards to using the rear always on 12V outlet while vehicle is off to power my National Luna fridge.

Normally in my LX, it's plugged in while driving and then switched over to my external portable LiFePo4 battery (3kw). If the 4XE main pack automatically tops off 12V battery, I'm less incline to bring the external battery esp if there's 15kw of potential energy usable. Read the supplement owner's manual but didn't find anything.
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cutandrun

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Does the 12V battery automatically get top off from the main pack battery when it hits a certain voltage? Question is in regards to using the rear always on 12V outlet while vehicle is off to power my National Luna fridge.

Normally in my LX, it's plugged in while driving and then switched over to my external portable LiFePo4 battery (3kw). If the 4XE main pack automatically tops off 12V battery, I'm less incline to bring the external battery esp if there's 15kw of potential energy usable. Read the supplement owner's manual but didn't find anything.
I hope so. I will be using my powered cooler while at the beach tomorrow. If not, does anyone know how to jump start a PHEV? :jk:
 

Jeeperz Kreeperz

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Bumping this thread, as I’m curious about this as well. Had a 2018 JLUS, and I could run down that main battery pretty quick with my fridge running in hot weather.

Anyone have any insight on this?
 
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ipizzaipizza

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Bumping this thread, as I’m curious about this as well. Had a 2018 JLUS, and I could run down that main battery pretty quick with my fridge running in hot weather.

Anyone have any insight on this?
Read some posts on FB groups where it's been mentioned it doesn't auto top 12V battery.
 

Black96z

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In my testing, the 4XE does not auto top off the battery while parked. When it is plugged in and charging, it also charges the 12V. If you put the jeep is ACC mode or Run mode, it charges the battery. I'd guess that as long as you don't run down the battery enough that the 12V can not close the contactors inside the battery pack, then you should be fine. I do not know how much current it takes to close the contactors for the traction pack though. Also, unlike a gas model, just sitting there the charging module can provide the full charging current, unlike an alternator that has to have the engine revving a little bit. So just clicking on the jeep to ACC mode or run mode, you will be applying 2400 watts to the battery. It should be able to top off the battery in 10-20 minutes. Also, if you click the jeep on to ACC mode, it will stay on for 15-20 minutes and then shut off.

I am thinking about just swapping the 12V for a deep cycle and letting the voltage drop to a pretty low cutoff and seeing if it still has the power to close the contacts and start charging.
 

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ipizzaipizza

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In my testing, the 4XE does not auto top off the battery while parked. When it is plugged in and charging, it also charges the 12V. If you put the jeep is ACC mode or Run mode, it charges the battery. I'd guess that as long as you don't run down the battery enough that the 12V can not close the contactors inside the battery pack, then you should be fine. I do not know how much current it takes to close the contactors for the traction pack though. Also, unlike a gas model, just sitting there the charging module can provide the full charging current, unlike an alternator that has to have the engine revving a little bit. So just clicking on the jeep to ACC mode or run mode, you will be applying 2400 watts to the battery. It should be able to top off the battery in 10-20 minutes. Also, if you click the jeep on to ACC mode, it will stay on for 15-20 minutes and then shut off.

I am thinking about just swapping the 12V for a deep cycle and letting the voltage drop to a pretty low cutoff and seeing if it still has the power to close the contacts and start charging.
Maybe in future, Jeep will do a software update to make this possible. So much energy under those seats for other outdoor applications.
 

michail

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Already been a report of an overnight dead 12v, so the system doesn't prevent it. I suspect ACC mode would correct it. But that only will run for 15 minutes or so.
 

SnB4xe

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I purchased a Domeric refrigerator to take camping. My plan is to turn off the climate control and remote start the Jeep once a day. That should allow the vehicle to top off the LVB.
 
 



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