Do the mild hybrid Jeeps also have an aux batter?

Mousehunter

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Currious, just experianced the joy of a dead Jeep battery. I fought charging it for 2-3 days and finally chump started it. 15 minutes on my dual battery diesel and still needed my wife to gun the motor to pull it off.

Talked to the sales staff at the dealership while waiting for my wife to pick me up, Not a completely waste of time, they were clueless about everything, but did have the heater on.

Second question, but more effort to research, any bets on the diesel having ESS? My 2015 VW and 2017 Fords were immune (and all on their original batteries, errrr).

And yes, not happy with the battery situation. Never imagined a battery on a daily driver to go legs up in less than 6 months..
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Jeepsterfreak

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Yes. The BSG has a regular 12v battery and an auxillary 48V battery under the body near the gas tank.

It does not have an auxillary 12v battery like your V6.
 
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Mousehunter

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That is kind of what I was hoping. I read elsewhere the 12v handles cold starts while the 48 handles hot starts. Kind of odd to me they would want 2 starter voltages, but if true it should be able to run without the 48v battery and should be a normal jump on the 12v if it was dead.
 

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A 12v circuit to handle accessories as well as emergency jumps both to jump other and jump yourself

The 48v is to handle the generator (replaces alternator), when 48v battery is charged it starts sending current to the generator rather than the generator send current to the battery which helps turn the engine over. Hence why it's called a mild hybrid.
 

RussJeep1

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A 12v circuit to handle accessories as well as emergency jumps both to jump other and jump yourself

The 48v is to handle the generator (replaces alternator), when 48v battery is charged it starts sending current to the generator rather than the generator send current to the battery which helps turn the engine over. Hence why it's called a mild hybrid.
@Sheepjeep: thanks for this. Allow me to see if I've got this correct.

The 48v battery's s charge lies solely with the process of converting kinetic energy (the movement of the vehicle) into potential energy via the process of regenerative braking?

And no classic version of an alternator/generator

* found in nearly every other combustion based vehicle, that
* turns the potential energy stored in the chemical bonds of liquid fuel, into the kinetic energy of pistons, tied to a camshaft, tied to a rotating belt, tied to a generator, into the potential energy stored within a battery?

...or at least as the 48V and not the 12V battery is concerned?.... perhaps the latter 12v battery charging from a conventional alternator system.

Sorry--very confusing.:)
 

ormandj

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@Sheepjeep: thanks for this. Allow me to see if I've got this correct.

The 48v battery's s charge lies solely with the process of converting kinetic energy (the movement of the vehicle) into potential energy via the process of regenerative braking?

And no classic version of an alternator/generator

* found in nearly every other combustion based vehicle, that
* turns the potential energy stored in the chemical bonds of liquid fuel, into the kinetic energy of pistons, tied to a camshaft, tied to a rotating belt, tied to a generator, into the potential energy stored within a battery?

...or at least as the 48V and not the 12V battery is concerned?.... perhaps the latter 12v battery charging from a conventional alternator system.

Sorry--very confusing.:)
That's a really odd way to break things down.

The 48V system is just a generator/motor. Watch: for a brief overview. It's really simple technology.
 

RussJeep1

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That's a really odd way to break things down.

The 48V system is just a generator/motor. Watch: for a brief overview. It's really simple technology.
So

* no alternator
* the 48V battery gets it's power solely from regenerative braking, and
* makes its first priority charging the 12V conventional battery (given the absence of the alternator), and
* takes what's left over to help the engine overcome the inertia of being at a standstill, and not have to work as hard getting the rig moving, solely after a start stop event, or spinning yet another belt (the alternator)?

Is that right? If so, haters of ESS need "not apply" for 2.0L club membership? Can you even turn ESS off on these rigs?

Simple, as you say, at least IMHO, at 60,000 feet. On closer examination though there appeart to be a LOT of parts to this, and I only hope proven enough technology to not cause failure given all the additional communication between components.

Still more I hope FCA spelt out the troubleshooting of problems with this system for techs in case there are issues.
 

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And more. The second one is very informative.


 
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ormandj

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So

* no alternator
* the 48V battery gets it's power solely from regenerative braking, and
* makes its first priority charging the 12V conventional battery (given the absence of the alternator), and
* takes what's left over to help the engine overcome the inertia of being at a standstill, and not have to work as hard getting the rig moving, solely after a start stop event, or spinning yet another belt (the alternator)?

Is that right? If so, haters of ESS need "not apply" for 2.0L club membership? Can you even turn ESS off on these rigs?

Simple, as you say, at least IMHO, at 60,000 feet. On closer examination though there appeart to be a LOT of parts to this, and I only hope proven enough technology to not cause failure given all the additional communication between components.

Still more I hope FCA spelt out the troubleshooting of problems with this system for techs in case there are issues.
It replaces the alternator, and in the Jeep's case, supplies 70ft/lb of near instantaneous torque in this application until the engine comes up to speed. Yes, it serves as the alternator for the 12V system as well as the 48V system. It does support regenerative braking to assist in charging as well as reduce brake wear (effectively engine braking).

It's connected directly to the crankshaft via a belt. It's an electric motor. There's a secondary battery pack for it, which has charging and thermal control circuits. There's a coolant system to keep the heat managed properly. None of this is horribly complex, even from a less than 60k ft view. IMO you're making a mountain out of a molehill, but we're all entitled to our opinions. Time will tell how this works out, but so far, the folks with RAM trucks have been happy with it and haven't encountered any major issues that I've seen. Haven't seen any with the Jeeps in owner's hands yet, but it's only been 4 months or so. We'll know in a year or two more. FCA has an 80k warranty on these systems, so I'm not terribly concerned.

As for ESS, I think it can still be defeated, but there's really no point. It's almost imperceptible unlike vehicles with traditional alternators. Go test drive one so you can see for yourself.

Re: troubleshooting, of course FCA did. All auto manufacturers create relatively detailed service manuals which cover just about any failure you can think of. The problem is, most techs don't seem to read or use these, and if they encounter anything even remotely different than the exact scenario listed, they have absolutely no idea to reason about the problems mechanically anymore. Everyone seems to hire people with no ability to use logic to solve problems, so it's rare to find good techs who can even follow a service manual well, let alone diagnose/troubleshoot something that isn't a 100% for something in it.

I would hope an entry level tech would be able to look at a simple motor, battery, and coolant system with a charging controller and cooling controller and diagnose issues. If the controllers are faulty, you'll see it in coolant pump operation or voltage supply, so it's not some magical tech that nobody can understand, it's all stuff that's been in cars since we went away from air cooling systems. If the controllers fail, you'll be able to see the symptoms. It's not like the techs have to debug the circuits and repair the controllers; they'll just swap them out _if_ they fail. Those failures should be infrequent considering the (my assumption) hardened design that is likely present in this system.

Also consider that the failure of the 48v system shouldn't kill the vehicle, it will still operate. You just won't have the benefit of the full system during the time until you have it repaired under the 80k warranty. I believe it also falls back to the 12v starting system when the temperatures drop fairly low, likely due to the 48v battery composition not being as efficient when cold.

We could go back and forward on this for eons, we'll just have to see what happens in a year or two. FCA seems to have remarkable talent in finding ways to make something simple/easy fail (see: welds on frames) so I'm not about to say it'll be perfect. I will state the technology itself is relatively simple, and shouldn't prove to be a major problem unless FCA made some serious missteps with the implementation on the Jeeps. It's already doing fine on the RAMs.
 
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RussJeep1

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Thanks @Jeepsterfreak

So energy comes from shift changes too, not just braking, at least on the Ram trucks discussed.

;)And in the first video, Mark Williams of PickupTrucks.com could have done (IMHO) the Voice over the 1960s version of Rudolph the Red Nosed Reindeer, narrated by Burl Ives:;)

 

RussJeep1

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IMO you're making a mountain out of a molehill, but we're all entitled to our opinions....
I'm only concerned that the added features *might* be something else to go wrong, and that a tech will have trouble fixing. I'm not forecasting bad outcomes with this design...and I like systems, including this one, that cause vehicles to better manage their energy and consume less fuel. In fact the ESS battery here (the 48V) is larger than the conventional one, opposite to the Pentastar based JLs ESS battery. As the second video @Jeepsterfreak posted details, that means longer times without need for the engine to recrank at stops, and when ESS recrank does occur, it will like become less perceptible than in the Pentastar based JLs.

I'm an engine braker when it comes to slowing the rig. I wonder how my driving habits might change under this system. Will downshifting to slow down be sent, rather than to the transmission and engine, to the regenerative braking system even though the brake pedal hasn't been pressed.

In fact, this stuff in time will likely stop becoming a rig's features and become standard, and rigs that don't have it will likely stand out for such deficiency.

I'm sorry if I left the impression that I was more down on this tech than simply interested in understanding it. You've got to love a system that not only captures wasted energy, but in doing so reduces wear and tear on moving parts like brake pads.
 

ormandj

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I'm only concerned that the added features *might* be something else to go wrong, and that a tech will have trouble fixing. I'm not forecasting bad outcomes with this design...and I like systems, including this one, that cause vehicles to better manage their energy and consume less fuel. In fact the ESS battery here (the 48V) is larger than the conventional one, opposite to the Pentastar based JLs ESS battery. As the second video @Jeepsterfreak posted details, that means longer times without need for the engine to recrank at stops, and when ESS recrank does occur, it will like become less perceptible than in the Pentastar based JLs.

I'm an engine braker when it comes to slowing the rig. I wonder how my driving habits might change under this system. Will downshifting to slow down be sent, rather than to the transmission and engine, to the regenerative braking system even though the brake pedal hasn't been pressed.

In fact, this stuff in time will likely stop becoming a rig's features and become standard, and rigs that don't have it will likely stand out for such deficiency.

I'm sorry if I left the impression that I was more down on this tech than simply interested in understanding it. You've got to love a system that not only captures wasted energy, but in doing so reduces wear and tear on moving parts like brake pads.
What a classy and well reasoned response. I apologize for being a bit harsh in my own.

There are (absolutely) areas for improvement, and I suspect over another ten year cycle, we will see hybrid electric or full-electric vehicles start taking over. I am completely excited about this; many view electrical systems as an area of complexity to fail, I view it as an area of complexity to remove. Wear and tear on mechanical systems is what gets you eventually, electron migration is a slow process and not something we need to worry about. Battery technology will get there, and when we have a motor in each wheel and software controlling it, Jeeps become an entirely new beast.

I just hope I see the day it becomes available, affordable, and reliable. No first year (or two) with Jeep when it comes to a full electric drivetrain, hah. It isn't the complexity that worries me, it's the lack of attention to detail. Shareholders in the short-term-gains world kill companies and good things. Penny wise, pound foolish.
 
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