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AndySpill
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If you wish to jumpstart the dual AGM battery JL from solely the auxiliary battery I would be inclined to locate the two factory black cables that are on the main battery’s negative post.
One of those cables has as its distal end the body ground on the front passenger fender. That cable should remain connected. It is the other cable that I would disconnect and attach temporary to the negative side of your jump starter.
The jumpstarter’s positive side can go on the main battery’s positive post.
That is not a typo. I did mean to say the main battery.
There may be better options here depending on what you are seeking to accomplish.
Once cranked reconnect that cable back.
One of those cables has as its distal end the body ground on the front passenger fender. That cable should remain connected. It is the other cable that I would disconnect and attach temporary to the negative side of your jump starter.
The jumpstarter’s positive side can go on the main battery’s positive post.
That is not a typo. I did mean to say the main battery.
There may be better options here depending on what you are seeking to accomplish.
Once cranked reconnect that cable back.
Ratbert
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Am I missing something? You jump start a vehicle, not a battery.
If the aux battery is dead then the main is dead too. Ignore the aux in the equation and treat it like it's not there.
If the aux battery is dead then the main is dead too. Ignore the aux in the equation and treat it like it's not there.
Terrymo
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Just to clarify, are you asking about using an N1 N2 fused jumper to defeat the aux battery, or actually jump starting your Jeep from the aux battery?
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Jebiruph
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Jumpstarting through the N1 terminal bypasses the aux battery.
https://www.jlwranglerforums.com/forum/threads/ess-jumpstarting-main-battery-vs-n1-terminal.87726/
AndySpill
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In light of Sari's @SariK additional info are we not missing the point?
Sari: if your Aux is dead and you want to get going, please consider bypassing this battery. The steps are straightforward and can be provided on request.
If you don't want to run ESS events I'd suggest effecting this bypass permanently. If not, then at least for long enough to get you going.
You have a 2019 correct? It was my understanding that only in early model 2018s would an Aux battery (without TSB 18-092-19) not attempt a crank if this battery lacked ample power. Later model years, on second crank attempt would bypass this Aux battery voltage requirement and attempt to crank off the main battery. So if you can't crank maybe both batteries are dead and possible shot.
Sari: if your Aux is dead and you want to get going, please consider bypassing this battery. The steps are straightforward and can be provided on request.
If you don't want to run ESS events I'd suggest effecting this bypass permanently. If not, then at least for long enough to get you going.
You have a 2019 correct? It was my understanding that only in early model 2018s would an Aux battery (without TSB 18-092-19) not attempt a crank if this battery lacked ample power. Later model years, on second crank attempt would bypass this Aux battery voltage requirement and attempt to crank off the main battery. So if you can't crank maybe both batteries are dead and possible shot.
AndySpill
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I'm beginning to think https://www.jlwranglerforums.com/forum/threads/3-6l-ess-battery-diagram.14401/ the above an adequate way to charge an Aux battery otherwise capable of accepting charge, but am concerned that at the point of crank, where the Power Control Relay (PCR) is energized for a moment, and this normally closed relay is opened, that the positive side of the jumper starter's connection to the Aux battery vis a vis the main battery's positive terminal may be broken.
And again, even if was an unbroken connection, I'm not sure that charging, rather than bypassing the Aux battery here is the best way to go.
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Ratbert
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The aux battery doesn't / can't start the Jeep. It's nowhere near powerful enough.
It's at 98%. What makes you think it's faulty?
AndySpill
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One, granted with ample power, which I doubt our OP has, alone, can.
(After the PCR separates the batteries for an instant to effect its voltage test, all the (connected) batteries are brought back together to effect the cold crank.)
AndySpill
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I'm confused Jerry @Jebiruph
https://www.jlwranglerforums.com/fo...ry-consolidated-information.25377/post-602294
As per the diagram, and provided the PCR isn't stuck open, wouldn't hooking the positive side of a jumpstarter to N1 be a direct connection to the positive terminal of the Aux battery, not bypass it, that along with hooking the negative side of the jump starter up to a disconnect cable "A" in the above linked diagram, directly energize the Aux battery?
Jebiruph
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The link I provided explains the difference. When you jumpstart connected to the main battery, the jumpstart power has to go to the aux battery before it goes to the electronics. When you jumpstart connected to N1, the jumpstart power is directly connected to the electronics.
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