Jumperless Aux Battery Bypass

[ScotM]

I will add this to my previous comment. Not everything is getting powered during a cold start. Accessories like the heater and radio are not powered during a cold start, unlike an ESS restart where everything is powered. All of the JL/JT battery systems are designed so a that an ESS restart where everything is powered involves 2 batteries, one for the electronics and one to start the engine.

Also, knowing that it's possible for an ESS component to fail and prevent the separation of batteries during an ESS event, the Jeep engineers allow for 6 ESS events from a single battery before disabling the ESS system. They evidentially must not have been too concerned about damage to the system from the 6 single battery ESS restarts.

I installed an auto stop eliminator, just to avoid any ESS issues.

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[AllMoparParts.com]

@AllMoparParts.com
Benny, could you please check if the "metal shunt" between N1 & N2 can be purchased? This shunt is found on etorque Jeeps next to the fuse box (e.g., V6 etorque, cuz no Aux battery)

See photo of shunt/connector between N1 & N2 circled (took photo from someone else's post).

No I am sorry I do not see that being serviced separately from the entire PDC

- Benny

 

[jax501]

No I am sorry I do not see that being serviced separately from the entire PDC

- Benny

Thank you for checking.
That metal shunt might actually be integrated into the fuse array?
https://www.allmoparparts.com/sku/68368854aa.html#col-fitment

 

[AllMoparParts.com]

Thank you for checking.
That metal shunt might actually be integrated into the fuse array?
https://www.allmoparparts.com/sku/68368854aa.html#col-fitment

While it does look like this if you look at the side where the shunt is located its opposite, So I do not believe so.

Below is where I think we are seeing the Array shunt

- Benny

 

[azwjowner]

@AllMoparParts.com
Benny, could you please check if the "metal shunt" between N1 & N2 can be purchased? This shunt is found on etorque Jeeps next to the fuse box (e.g., V6 etorque, cuz no Aux battery)

See photo of shunt/connector between N1 & N2 circled (took photo from someone else's post).

If you don't mind waiting a few months, by the end of the summer (maybe sooner) I will do the aux delete and report back on how well the bus bar I bought from Amazon fits there.

 

[ScotM]

While it does look like this if you look at the side where the shunt is located its opposite, So I do not believe so.

Below is where I think we are seeing the Array shunt

- Benny

If you don't mind waiting a few months, by the end of the summer (maybe sooner) I will do the aux delete and report back on how well the bus bar I bought from Amazon fits there.

I’m ding a N1 to N3 jumper on Monday, I’ll post it once I start the jeep

 

[Jebiruph]

While it does look like this if you look at the side where the shunt is located its opposite, So I do not believe so.

Below is where I think we are seeing the Array shunt

- Benny

There's a good use for all those blown fuse arrays, cut off the N7 to N8 flange to use as an N1 to N2 shunt. It will need shimmed with an appropriate thickness washer to compensate for the difference in height of the terminals.

 

[gm920]

To eliminate some confusion I think the removal of the Aux battery, PCR and wiring should be a separate thread from the "Aux delete", where the battery and wiring are left in place. There has been tons of info on the "Delete" procedure.
If you are "Removing" everything just take the Aux battery positive that is connected to N1 and N3 and connect it to the Main battery positive. Of course you can and probably should still remove Fuse F42

 

[Mguy]

To eliminate some confusion I think the removal of the Aux battery, PCR and wiring should be a separate thread from the "Aux delete", where the battery and wiring are left in place.

Apparently, readers of this thread did a “bypass” of post #780 and what immediately followed.

 

[ScotM]

To eliminate some confusion I think the removal of the Aux battery, PCR and wiring should be a separate thread from the "Aux delete", where the battery and wiring are left in place. There has been tons of info on the "Delete" procedure.
If you are "Removing" everything just take the Aux battery positive that is connected to N1 and N3 and connect it to the Main battery positive. Of course you can and probably should still




A lot of that hijacking is my fault. I could only find 3 threads on removing everything to eliminate the aux battery, and this thread had the most information, despite its title. There were thousands of isolate negative aux cable off of main and remove fuse 42, not to mention the number of videos. At any rate , I think this thread has the most comprehensive information available on how to remove all the cabling, including the aux positive cable. I’m in agreement that it would be nice to have the information in its own thread.

 

[Mguy]

A lot of that hijacking is my fault.

No blame at all. Forums like this are almost always a disorganized mess of good and bad information. Readers in need of good info naturally go where it is most likely to come from, and this thread is clearly amongst the best on this forum.

 

[JK’s Ruby]

This is my first post but I have been using this forum for a while. There is a wealth of information and I really appreciate all of the contributors.

Last year I purchased a used 2020 JLU Rubicon for my wife to upgrade from a 2014 JKU that provided years of reliable service. Since the purchase it has left her stranded three times due to issues described in this thread. The last time it happened it was taken to a dealership where the PCR and alternator were replaced. They said both batteries were good.

Last night it stranded her for the third time. I pulled the F42 fuse, disconnected the auxiliary battery negative, installed a new Group 94H7 AGM Battery, and a fused jumper from N1 to N2 to start the jeep and load it on the trailer.

When I remove the fuse in the jumper the jeep dies. Does this jumper need to remain in place to bypass the Aux Battery? I have read through many of these threads and thought that the removal of fuse 42 eliminated the need for the jumper.

Again, thanks to all who take time to reply to these questions. The dealership has a 3 week wait for repairs and the information provided in this forum saves people like me a lot of time and money.

 

[Jebiruph]

This is my first post but I have been using this forum for a while. There is a wealth of information and I really appreciate all of the contributors.

Last year I purchased a used 2020 JLU Rubicon for my wife to upgrade from a 2014 JKU that provided years of reliable service. Since the purchase it has left her stranded three times due to issues described in this thread. The last time it happened it was taken to a dealership where the PCR and alternator were replaced. They said both batteries were good.

Last night it stranded her for the third time. I pulled the F42 fuse, disconnected the auxiliary battery negative, installed a new Group 94H7 AGM Battery, and a fused jumper from N1 to N2 to start the jeep and load it on the trailer.

When I remove the fuse in the jumper the jeep dies. Does this jumper need to remain in place to bypass the Aux Battery? I have read through many of these threads and thought that the removal of fuse 42 eliminated the need for the jumper.

Again, thanks to all who take time to reply to these questions. The dealership has a 3 week wait for repairs and the information provided in this forum saves people like me a lot of time and money.

Check for a blown N3 fuse, you may have blown it at some point during the process.

 

[Mguy]

Last night it stranded her for the third time. I pulled the F42 fuse, disconnected the auxiliary battery negative, installed a new Group 94H7 AGM Battery, and a fused jumper from N1 to N2 to start the jeep and load it on the trailer.

When I remove the fuse in the jumper the jeep dies. Does this jumper need to remain in place to bypass the Aux Battery?

An N1-N2 jumper bypasses the aux battery cabling, which provides power to the N1 loads (basically, the whole Jeep). As already suggested, seems like your N3 fuse, which is the power source for N1 loads through the aux battery cabling, is blown.

Not totally clear from your post whether your new main battery is still fully charged. If there is delay in getting to the electrical fix, best to bring that battery up to full charge sooner than later.

 

[JK’s Ruby]

The N-3 fuse was blown. Luckily I had a spare fuse array in the glove box. The jeep cranked right up without the jumper.

Thanks again for the assistance!

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