Drained Battery, Any jumpstart tips??

[RussJeep1]

So by hooking up jumper cables in the typical fashion, you cannot start a JL? What?

How does the computer know that the 12+ volts coming in is coming from another vehicle battery and not its own vehicle battery? What does it care, as long as it's getting the voltage?

My thoughts.

I have a 110AC to 12V DC car battery charger/jump starter. It has 3 settings. The first delivers power as if the vehicle batteries were charged, for immediate starting. The later two settings are high and low trickle settings for actually battery charging, as opposed to the aforementioned first setting: which is for jump starting the rig.

With the main and ESS battery hooked up parallel, and the aforementioned appliance in jump start mode, hooked up to the positive and negative terminals where both batteries connect, wouldn't the vehicle's computer be "fooled" into thinking both batteries are functional and permit engine cranking?

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[Karl_in_Chicago]

The two batteries are in parallel when ignition is OFF, and you can trickle charge as normal when OFF, when you push the start button they are then independent circuits.

OK, I stayed out of the great ESS debates as I'm really ambivalent about the whole thing. Also knowing that if it did end up really bugging me I can disable it either on a drive-by-drive basis or more permanently with something like the Tazer made it kind of a non-issue for me. But hearing that you can't jump start your vehicle due to this design . . . that's a whole different story. I get that hooking up a charger and *waiting* should eventually resolve it but this assumes that the vehicle is somewhere near electricity. What if, God forbid, the vehicle was in the great outdoors . . . or even the MALL . . . and the objective is to just get it going NOW? That's just crazy/stupid.

 

[AlamedaJeep]

Not being able to jumpstart would seem like an incredible oversight. I haven't had the problem (and am still waiting on delivery of my Jeep) so I have no personal experience, but there are standard jump start procedures listed in the Owners Manual.

Is the manual just not accurate, or is there something else going on?

 

[obwahn]

OK, I stayed out of the great ESS debates as I'm really ambivalent about the whole thing. Also knowing that if it did end up really bugging me I can disable it either on a drive-by-drive basis or more permanently with something like the Tazer made it kind of a non-issue for me. But hearing that you can't jump start your vehicle due to this design . . . that's a whole different story. I get that hooking up a charger and *waiting* should eventually resolve it but this assumes that the vehicle is somewhere near electricity. What if, God forbid, the vehicle was in the great outdoors . . . or even the MALL . . . and the objective is to just get it going NOW? That's just crazy/stupid.

I just checked the owner's manual. Nothing special listed in there about jump starting. Just hook it up like we've all been told to do and fire it up.

 

[RussJeep1]

My thoughts.

I have a 110AC to 12V DC car battery charger/jump starter. It has 3 settings. The first delivers power as if the vehicle batteries were charged, for immediate starting. The later two settings are high and low trickle settings for actually battery charging, as opposed to the aforementioned first setting: which is for jump starting the rig.

With the main and ESS battery hooked up parallel, and the aforementioned appliance in jump start mode, hooked up to the positive and negative terminals where both batteries connect, wouldn't the vehicle's computer be "fooled" into thinking both batteries are functional and permit engine cranking?

Wait. I think I get it now. At the point of attempting a crank, no longer are the two batteries in parallel, but rather isolated.

Ok..what hardware do I need, what procedure do I follow to get the red wire of my jumper cables to N5, (assuming I even need to go to N5) and the black ground goes where....?

Please dumb it down for me. How do I jump start? My jumper cable's alligator clips go where....? I open the main fuse box where...?

 

[GRAK]

Yes please explain and even photos would be warranted - this is incredibly important. Can't believe it hasn't been jumped yet.

 

[Rhinebeck01]

snip:

But hearing that you can't jump start your vehicle due to this design . . . that's a whole different story. I get that hooking up a charger and *waiting* should eventually resolve it but this assumes that the vehicle is somewhere near electricity. What if, God forbid, the vehicle was in the great outdoors . . . or even the MALL . . . and the objective is to just get it going NOW? That's just crazy/stupid.

Reality is no one here has any real first hand experience with this jump start the JL thing...

I'm sure in the coming days/weeks, etc., we will all hear first hand experiences that will make it crystal clear how to handle dead JL batteries and such. Again, not enough first hand info on the subject right now...

.

 

[Rhinebeck01]

Forgot to mention.. There was a forum post a few months ago where a forum member said he had the JL's main battery disconnected and the JL still started. Many of us at that time deduced the ESS/Aux battery was in fact the battery that actually started the JL. Again, the main battery did not have to be present. So we have known this for some time now.

Also, another forum member said he trickle charged the ESS/Aux battery using N4 and a neg.

It might come down to it that if the ESS/Aux battery is dead and thus the JL will not start, that you can just jump start it by hooking up to N5 and negative and the JL will start. Question is will the JL stay running if the JL's system sees the ESS is not charged at the proper level. Will it just shut down... or will it stay running until you turn the vehicle off.. Of course then, the vehicle will not restart as the ESS/Aux battery is depleted.

So, a lot of unknowns here. Hopefully, @RadicalMatt will come back here and tell us first hand what he saw and how he ended up handling the situation he was faced with. Looking forward to his followup post.

.

 

[mazeppa]

See (he knows a lot more the me):

 

[mwilk012]

Where is the video where he goes over the wiring diagram? I'm curious to see this.

 

[JIMBOX]

This is one of the reasons I gotta stick00

You can "POP THE CLUTCH"-

W.E.

JIMBO

 

[RussJeep1]

Some batteries won't take a charge due to defect and/or age. I respect that.

Upon cranking the vehicle the main and ESS/start battery are isolated. I respect that.

But when parked the two batteries in connected in parallel, correct? And wouldn't that imply that either would be capable of charging the other, assuming the failing battery is capable of accepting a charge?

Maybe, as already stated, we just don't know enough about not only the wiring, but the computer's logic on things. For example, as previously mentioned, it seems unknown what a started JL with a dead ESS/start battery does. We've learned ESS won't kick in (I think) when the ESS/start battery's voltage is coming up low, but who knows who happens when that voltage comes back essentially as absent.

I think most of us can agree that we could use a more immediate solution to getting the rig going, particularly when not at home, than plugging our trickle charger into the 110AC outlet that might not be present, and waiting. I just really want to know what it is. And if, for example, in involves carrying a spare ESS battery, charged, in the rig, I'd like to know that and have one, at least for road trips.

 

[mwilk012]

Some batteries won't take a charge due to defect and/or age. I respect that.

Upon cranking the vehicle the main and ESS/start battery are isolated. I respect that.

But when parked the two batteries in connected in parallel, correct? And wouldn't that imply that either would be capable of charging the other, assuming the failing battery is capable of accepting a charge?

Maybe, as already stated, we just don't know enough about not only the wiring, but the computer's logic on things. For example, as previously mentioned, it seems unknown what a started JL with a dead ESS/start battery does. We've learned ESS won't kick in (I think) when the ESS/start battery's voltage is coming up low, but who knows who happens when that voltage comes back essentially as absent.

I think most of us can agree that we could use a more immediate solution to getting the rig going, particularly when not at home, than plugging our trickle charger into the 110AC outlet that might not be present, and waiting. I just really want to know what it is. And if, for example, in involves carrying a spare ESS battery, charged, in the rig, I'd like to know that and have one, at least for road trips.

I think seeing the schematic would help quite a bit in figuring this out.

 

[sarum87]

what did you have plugged into your rear 12 volt that drained your battery????

 

[RussJeep1]

I think seeing the schematic would help quite a bit in figuring this out.

Agreed, but no less important than understanding the computer algorithms followed based upon the currents flowing in those wires/resistors/relays/capacitors etc.

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