Sponsored

Rhinebeck01

Well-Known Member
Joined
May 9, 2018
Threads
155
Messages
11,871
Reaction score
17,110
Location
Multiple places..
Vehicle(s)
'18 JL Rubi, '22 Prevost M H3-45,'01 Harley FatBoy
Yes , you can get at the Aux battery, from above but..... A lot more to the exchange, going from up above though.. A lot more to screw up, too.

The Factory Service Manual has you fooling with the fender liner.... yuk...

Anyway, when I watched my tech friend changing out the Aux battery on a JL, he mentioned to me, that he would rather just pull the whole fender flare, versus fooling with the fender liner in order to get to the Aux battery... He told me it would be so much easier/faster..

Oh, prior to ever pulling a JL fender flare, you might just want to purchase a couple of fender flare clips, just in case you break one.

You can get them here for less than a dollar each. https://www.quadratec.com/p/omix/fender-flare-clip-wrangler-jl-gladiator-jt-11609.41

So, I remembered seeing this video a year or so ago and geeez, my tech friend had the right idea, in regard to just easily pulling the flair to gain easy access to the Aux battery.

Here is the video... it is worth the time to watch it, in it's entirety.. ESPECIALLY, if someday you yourself might want to replace your Aux battery yourself.

Sponsored

 

Dkretden

Well-Known Member
First Name
David
Joined
Jan 29, 2019
Threads
57
Messages
2,533
Reaction score
3,527
Location
Denver, CO
Vehicle(s)
2020 JLUR 3.6L
This is very good. I learned something. Thank you.

this is the same YouTube dude who had the original video out to go through the fuse box.

this seems a whole lot easier with less chance of damaging anything. And the clips for a buck a piece is great to see as well.
 

rustyshakelford

Banned
Banned
Banned
First Name
Brett
Joined
Sep 14, 2018
Threads
41
Messages
2,430
Reaction score
3,016
Location
Navasota, TX
Vehicle(s)
2019 JLUR-8 speed 2020 F-350
Absolutely, can pull a front fender in 2-3 mins. Much easier than fighting with everything else! Great tip!

brett
 

Htfan

Well-Known Member
First Name
Jeff
Joined
Nov 18, 2019
Threads
18
Messages
1,183
Reaction score
1,134
Location
Orange County, CA
Vehicle(s)
2018 JLU Sport S - 3.6L
Vehicle Showcase
1
This is great info! I didn't realize that you could get at the aux/ess battery that way. However, it seems stocking up on plastic clips is the way to go. I imagine clip breakage is probable.
 

ErAcEr

Well-Known Member
First Name
Matthew (Mateo)
Joined
Jun 6, 2019
Threads
4
Messages
334
Reaction score
460
Location
Indianapolis, IN
Vehicle(s)
2018 JLU, 2021 ZH2 , 2018 Z900, 2013 Vulcan 1700
Occupation
Engineer/Technician
For those that are interested, here is a pic of the Aux battery and the part # of the Aux battery.

Aux Battery - JL.jpg
How do I know if my aux battery is bad? Im sure its in another post somewhere but lazy to go searching.
 

Sponsored

OP
OP
Rhinebeck01

Rhinebeck01

Well-Known Member
Joined
May 9, 2018
Threads
155
Messages
11,871
Reaction score
17,110
Location
Multiple places..
Vehicle(s)
'18 JL Rubi, '22 Prevost M H3-45,'01 Harley FatBoy
OEM Aux battery. It's Mopar part # is 56029759AB

For an aftermarket Aux battery for your JL, ask the parts guy for an
Group Size 400, "AUX14" battery.

Aux battery aftermarket replacements:

DieHard Platinum AGM Battery, BCI Group Size 400, 200 CCA
Part # AUX14-1

Super Start Platinum Auxiliary Battery Group Size 400
Part #AUX14

Interstate MTX-AUX14

ACDelco Professional Gold 88866185 AUX14-200 battery

Braille (Part# B14115) I5Ah 360CCA
Tests from factory at 483 Crank Amps. Wt. 11.5 lbs.


.
 
Last edited:
OP
OP
Rhinebeck01

Rhinebeck01

Well-Known Member
Joined
May 9, 2018
Threads
155
Messages
11,871
Reaction score
17,110
Location
Multiple places..
Vehicle(s)
'18 JL Rubi, '22 Prevost M H3-45,'01 Harley FatBoy
Here is a snip from the Factory Service Manual.. Note, that the service manual says to first, Disconnect and Isolate the negative battery cable(s) . IMPORTANT --They are referring to the negative battery cables up top / in the engine compartment, on the Main battery!

After doing that, you remove the 3 bolts from the supplemental battery tray (Aux's battery tray) and lower the Aux battery down a bit.... just enough so that you can get to and disconnect the pos and neg cables (then isolate them) from the Aux battery. After both the cables are disconnected, your Aux battery is free to drop down and to be replaced.

Jeep Wrangler JL Aux Battery replacement the easy way... pull the fender flare aux-replace
 
OP
OP
Rhinebeck01

Rhinebeck01

Well-Known Member
Joined
May 9, 2018
Threads
155
Messages
11,871
Reaction score
17,110
Location
Multiple places..
Vehicle(s)
'18 JL Rubi, '22 Prevost M H3-45,'01 Harley FatBoy
For those that are interested, here is a pic of the OEM Aux battery and the part # of the Aux battery.

For an aftermarket Aux battery for your JL, ask the parts guy for an
Group Size 400, "AUX14" battery.

Jeep Wrangler JL Aux Battery replacement the easy way... pull the fender flare Aux Battery - JL
 
Last edited:

EU_Wrangler

Well-Known Member
Joined
Feb 29, 2020
Threads
6
Messages
196
Reaction score
104
Location
Norway
Vehicle(s)
MY20 JLUR 2.2 EcoDiesel
Here is a snip from the Factory Service Manual.. Note, that the service manual says to first, Disconnect and Isolate the negative battery cable(s) . IMPORTANT --They are referring to the negative battery cables up top / in the engine compartment, on the Main battery!

After doing that, you remove the 3 bolts from the supplemental battery tray (Aux's battery tray) and lower the Aux battery down a bit.... just enough so that you can get to and disconnect the pos and neg cables (then isolate them) from the Aux battery. After both the cables are disconnected, your Aux battery is free to drop down and to be replaced.

Jeep Wrangler JL Aux Battery replacement the easy way... pull the fender flare Aux Battery - JL
Is the Factory Service Manual available to download? I can't find any thread in the forum related to the manual
 
OP
OP
Rhinebeck01

Rhinebeck01

Well-Known Member
Joined
May 9, 2018
Threads
155
Messages
11,871
Reaction score
17,110
Location
Multiple places..
Vehicle(s)
'18 JL Rubi, '22 Prevost M H3-45,'01 Harley FatBoy
Is the Factory Service Manual available to download? I can't find any thread in the forum related to the manual
@EU_Wrangler


Sure, if you want, you can buy the Factory Service Manual....

Get it here or do a Google search and find it/buy it elsewhere:

For 2018 SM:
https://www.factoryrepairmanuals.co...tory-service-manual-usb-original-shop-repair/

For 2019 SM:
https://www.factoryrepairmanuals.co...Omas4X0mHDbcR1GlHFXKyGgzxSrPMrKhoCGtUQAvD_BwE

For 2020 SM:
https://www.factoryrepairmanuals.co...Omas4X0mHDbcR1GlHFXKyGgzxSrPMrKhoCGtUQAvD_BwE

Past forum thread talking SM:
https://www.jlwranglerforums.com/forum/threads/2018-wrangler-jl-factory-service-manual.2637/
 

Sponsored

Rubi

Well-Known Member
First Name
David
Joined
Dec 25, 2016
Threads
3
Messages
447
Reaction score
218
Location
Connecticut
Vehicle(s)
‘18 Jeep JLR
Yes , you can get at the Aux battery, from above but..... A lot more to the exchange, going from up above though.. A lot more to screw up, too.

The Factory Service Manual has you fooling with the fender liner.... yuk...

Anyway, when I watched my tech friend changing out the Aux battery on a JL, he mentioned to me, that he would rather just pull the whole fender flare, versus fooling with the fender liner in order to get to the Aux battery... He told me it would be so much easier/faster..

Oh, prior to ever pulling a JL fender flare, you might just want to purchase a couple of fender flare clips, just in case you break one.

You can get them here for less than a dollar each. https://www.quadratec.com/p/omix/fender-flare-clip-wrangler-jl-gladiator-jt-11609.41

So, I remembered seeing this video a year or so ago and geeez, my tech friend had the right idea, in regard to just easily pulling the flair to gain easy access to the Aux battery.

Here is the video... it is worth the time to watch it, in it's entirety.. ESPECIALLY, if someday you yourself might want to replace your Aux battery yourself.

Excellent write-up, thanks.
 
OP
OP
Rhinebeck01

Rhinebeck01

Well-Known Member
Joined
May 9, 2018
Threads
155
Messages
11,871
Reaction score
17,110
Location
Multiple places..
Vehicle(s)
'18 JL Rubi, '22 Prevost M H3-45,'01 Harley FatBoy

rubileon

Banned
Banned
Banned
Joined
Jun 30, 2019
Threads
27
Messages
728
Reaction score
551
Location
Water over dirt planet
Vehicle(s)
JLUR RHD 3.6
For those that are interested, here is a pic of the Aux battery and the part # of the Aux battery.

Jeep Wrangler JL Aux Battery replacement the easy way... pull the fender flare Aux Battery - JL
Thanks for posting these!

It says the max charging voltage is 14.4 but I remember seeing mine at 14.5 or maybe 14.7 at times.

Also, to effectively bypass this but not to over tax the alternator, can't we replace it with a sufficient capacitor?
Sponsored

 
 



Top