Large rear eTorque battery to run auxiliary items?

JeepinJason33

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I have a 2021 JLUR 3.6 with the eTorque and am finding conflicting information out there regarding which battery bleeds down first. There are two batteries on my JLUR, the front main battery under the hood, and the rear large battery between the frame rails. There is not a third small aux battery under my battery in the engine compartment as in some of the other JL's. My question is, do the charging ports and accessories pull off of that battery when the vehicle is not running? If so, I have to imagine there is a fairly large reserve to run something like a ARB refrigerator. Does the reserve battery pull off the main battery once it is depleted? How would you hook solar up to this to ensure you are charging that battery?
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CptFloridaMan

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I have a 2021 JLUR 3.6 with the eTorque and am finding conflicting information out there regarding which battery bleeds down first. There are two batteries on my JLUR, the front main battery under the hood, and the rear large battery between the frame rails. There is not a third small aux battery under my battery in the engine compartment as in some of the other JL's. My question is, do the charging ports and accessories pull off of that battery when the vehicle is not running? If so, I have to imagine there is a fairly large reserve to run something like a ARB refrigerator. Does the reserve battery pull off the main battery once it is depleted? How would you hook solar up to this to ensure you are charging that battery?
All accessories run off the 12v battery. The 48v will charge the 12v while the jeep is running. I had my 12v battery go flat and stop holding a charge. Needed a jump like any other car. The interesting thing would be tapping into the 48v to actually use it for other things.

https://www.jlwranglerforums.com/fo...hybrid-system-components-mgu-cables-ppu.2140/
 
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JeepinJason33

JeepinJason33

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If the 48 volt battery charges the 12 volt battery there has to be a line coming in that you would think you could tap off of some how that is at 12 volts. It would be interesting to see if you could also charge it.
 

CptFloridaMan

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It would be very cool to see the aftermarket develop a voltage controller, that supports charging and discharging the 48v other than assisting the engine for half a rotation on the crank. If somehow we crammed larger batteries, and had a controller managing it all to run auxiliary things, and be able to charge from say solar. That’d be a sweet setup.

With the current dc converter Im sure it’s locked in for safety etc however.
 

Gee-pah

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All accessories run off the 12v battery. The 48v will charge the 12v while the jeep is running. I had my 12v battery go flat and stop holding a charge. Needed a jump like any other car. The interesting thing would be tapping into the 48v to actually use it for other things.

https://www.jlwranglerforums.com/fo...hybrid-system-components-mgu-cables-ppu.2140/
So Gabriel, in the spirit of the adage, "G-d helps those who help themselves," the 48 volt battery will only help the 12 volt battery if, at least from the factory, the 12 volt battery of the eTorque has, all on its own, enough power to initially effect the engine crank?

True?
 

don2510

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This is the same eTorque system used on the Ram pickups. When the engine is running, the motor/generator is supplying 48 volts to the 48 volt battery module. Inside the module, the 48 volts is stepped down to 14.2 volts and supplies the Jeep battery with a charge. If the engine is not running, no charging voltage is supplied. This is a function of the 48 volt battery module.
 

CptFloridaMan

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So Gabriel, in the spirit of the adage, "G-d helps those who help themselves," the 48 volt battery will only help the 12 volt battery if, at least from the factory, the 12 volt battery of the eTorque has, all on its own, enough power to initially effect the engine crank?

True?
Correct. So the 12v is the “normal” battery starts the jeep as normal. As @don2510 mentioned, the 48v generator charges the 48v battery and that charges the 12v. However, the 48v generator also acts as an assist up to 1500rpm. And also can apply sort of a regen mode when coasting and supplement the engine braking.

FCA initially said the generator unit can’t cold start the engine due to cold start characteristics. So the conventional starter is used for the first crank event when starting it.

Interestingly enough, Mercedes is doing this with newer cars and they seem to be using their 48v system to start the engine for any start up event.
 

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Anyone find a way to use the 48 bolt battery to power accessories yet?
 

PaulW

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How the JL & JT '21 3.6 Etorque battery system really functions. It works just like the Ram Etorque, but with different size 48v battery.

Yes the 12v battery will slowly loose its charge with time and with starting the motor. The 12v battery is not like previous JL batteries because it is bigger. In theory all the issues with dead batteries on older JLs should be gone.
The 48 v lion battery is disconnected by theJeep electronics until the motor is started . Then the 48 v battery charges the 12v battery thru an dc-dc charger device. The MGU which replaced the alternator charges the 48 v battery directly then if the 12v needs more energy when the motor is running the 48 v provides the power.
Hacks to get power from the 48v battery when the motor is off is not something that sounds realistic.
 

Derf123

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How the JL & JT '21 3.6 Etorque battery system really functions. It works just like the Ram Etorque, but with different size 48v battery.

Yes the 12v battery will slowly loose its charge with time and with starting the motor. The 12v battery is not like previous JL batteries because it is bigger. In theory all the issues with dead batteries on older JLs should be gone.
The 48 v lion battery is disconnected by theJeep electronics until the motor is started . Then the 48 v battery charges the 12v battery thru an dc-dc charger device. The MGU which replaced the alternator charges the 48 v battery directly then if the 12v needs more energy when the motor is running the 48 v provides the power.
Hacks to get power from the 48v battery when the motor is off is not something that sounds realistic.
Not to hijack this thread but I have a 3.6 with torque coming soon. From reading other post. Is there a clear answer if you can jump start a 3.6 with e torque?
 

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Member Oceanblue2019 has used the 48 volt battery to run a fridge and other 12 volt accessories with a DC to DC converter. Sort of wish I had gotten an e-Torque but it is not available with the 6 speed.
Gregj
 

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If you have evidence you took it in for an issue before the warranty expired, you are covered until the issue is resolved.
 

PaulW

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There is a thread on this forum that details how to use the 48v battery for accessories by using a DC-DC converter. Search it out
 
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