Aux battery - Missing F42 fuse

[jag]

2021 Jeep Wrangler JL 3.6 (no etorque)
My auto start stop and aux switches have quit working so I'm assuming the aux battery is bad. I've seen posts about pulling the F42 fuse and removing the aux battery negative to isolate the aux battery and avoid killing the main battery. My problem is that I'm missing that F42 fuse and the fuse terminals. Does anyone know why this would be? Again I don't have etorque. How would I go about isolating the aux battery in this situation without removing it? It's still under warranty but I can't get it into the dealership for a while.

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[Rhinebeck01]

2021 Jeep Wrangler JL 3.6 (no etorque)
My auto start stop and aux switches have quit working so I'm assuming the aux battery is bad. I've seen posts about pulling the F42 fuse and removing the aux battery negative to isolate the aux battery and avoid killing the main battery. My problem is that I'm missing that F42 fuse and the fuse terminals. Does anyone know why this would be? Again I don't have etorque. How would I go about isolating the aux battery in this situation without removing it? It's still under warranty but I can't get it into the dealership for a while.

@jag

Go out to your JL and take a picture of your Main battery. Pic straight down at the battery so I can see your pos and neg terminals. Post the picture here.

 

[jag]

@jag

Go out to your JL and take a picture of your Main battery. Pic straight down at the battery so I can see your pos and neg terminals. Post the picture here.

 

[Rhinebeck01]

@jag

Based on your picture, contrary to your belief your JL is an etorque JL.

 

[jag]

@jag

Based on your picture, contrary to your belief your JL is an etorque JL.

Interesting. I don't see any torque badging at all. Maybe I need to go over the window sticker again.
Do you know if there is a way to bypass the aux batter with etorque?

 

[Rhinebeck01]

Interesting. I don't see any torque badging at all. Maybe I need to go over the window sticker again.
Do you know if there is a way to bypass the aux batter with etorque?

You have an eTorque, JL...

To tell ... eTorque or not...

Pop the hood and in say 15 seconds you can take a looksee and tell if it is an etorque JL or not....

With eTorque ........and the JL, you will see the factory has placed a solid metal jumper between N1 and N2 in the Power Distribution Center (PDC).

You will also find that there is NO, Aux battery negative cable attached to the Main batteries Neg terminal... you will just see an available stud on the Main battery neg terminal, with no cable attached to it...

And indeed, the plastic box under the PDC/ hiding behind the passenger fender flare, is there... but it does not have an Aux battery in it.. it is just an empty box.

And of course, if you crawl under... with eTorque, you will see, the 48v battery box will be these... - (with battery) just ahead of the rear axle on the drivers side.

 

[Rhinebeck01]

Interesting. I don't see any torque badging at all. Maybe I need to go over the window sticker again.
Do you know if there is a way to bypass the aux batter with etorque?

An etorque JL does not have an Aux battery so you cannot bypass the aux battery.

 

[jag]

OK. Thank you.

 

[Rhinebeck01]

More then likely your Main is on the way out / is iffy and that is why you are getting seeing the ESS and Aux switches related messages. Pretty typical.

Buy and install a new Main yourself..... unless your JL is still covered under the 3 yr. 36,000 mi. warranty.

Read here: https://www.jlwranglerforums.com/forum/threads/??-main-battery-replacement-talk-jl-jt-?.100534/

By the way, you are not the 1st to not know they had etorque..

 

[jag]

Good to know. It's still under warranty. Only 2 years old. Thanks again!

 

[Rhinebeck01]

Good to know. It's still under warranty. Only 2 years old. Thanks again!

Since under warranty, have dealer eval.
At a dealership for a battery thing, it is wise to ask to talk to the Service Manager... again talk to the Service Manager and not the Service Writer.

Politely ask that he/she have the Tech, load test your battery and to provide you with a printout of load test in regard to your MAIN battery.

IF the battery fails the load test, then indeed you have an iffy battery and you can get the dealer to replace under warranty.

The load testing takes a couple of hrs. of shop time, so very often they will not do proper load testing, but say they did or not even mention load testing to you.

IF you do not see the load test printout you cannot be sure they actually did do load testing..

No load test done... showing bad battery ...... then they will just send you away and you will deal with the iffy Main til your warranty is no more then you will be stuck with paying for the battery.

 

[jag]

Sounds just like something that my dealership would try to pull. I will do that ASAP. Thank you for all of your help. By the way, I checked my sticker and sure enough it says etorque.

 

[Rhinebeck01]

Sounds just like something that my dealership would try to pull. I will do that ASAP. Thank you for all of your help. By the way, I checked my sticker and sure enough it says etorque.

No problem, I will send you a bill in the mail..

Again, politely ask to speak to the Service Manager. Swoooze him/her a bit and ask that the load test results be provided to you. That kinda puts the Service Manager on notice that you are not naive.... that you know load testing is needed when battery related issues are at hand..

Also.... if, if you are driving that JL little ... doing just short little trips, it could just be the battery is ok but you are not driving long enough for the alternator to charge the Main and that is the why for the ESS and aux messages.

 

[jag]

Thank you

 

[OBD]

One quick question.I have a 2021 3.6 non e-torque I plan on deleting the auxiliary battery.The ground on my main battery has a smaller ground cable on the inboard side of the engine attached with a small nut and the larger cable attached to the large stud towards the outside closest to the fender.I thought the larger cable was the main ground to the body? Mine looks like the opposite.I'm confused....lol which is not unusual!I can remove the large cable from the terminal easily,the small cable ....not so much.The small cable looks to be attached and on top of a sensor.Thanks in advance.

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