Sponsored

Aux Battery Problems

Lost1wing

Well-Known Member
First Name
Tim
Joined
Dec 22, 2020
Threads
24
Messages
2,606
Reaction score
2,845
Location
West Georgia
Vehicle(s)
2020 Jeep Gladiator Rubicon
Occupation
Retired AMT
Start with taking the ground off at either the fender or at the top plate on the main battery neg. If you take it off at the fender, you know you have both batteries disconnected. If you take it off at the top plate on the main neg, it is possible to take off the aux neg cable. Now you are left with holding it out of the way while you take the other cable off. No big deal, just be careful. If you leave these grounds unprotected with either positive cables still connected and touch them to ground, you may see some sparks. That would just be the car trying to energize the circuits. Leaving the grounds connected to the fender and at the top plate and reming the assy from the main neg post leaves you open to the fuse array going bad if a positive cable touches ground. Usually the 150amp N3. Now depending on the state of the Aux battery, you will see different indications of the failed fuse. A dead or very low voltage would give you what I believe the OP had. He correctedthe issue by moving the positive aux cable to the main positive. He shouldn't have to do that if the pcr was deactivated (f42) and N3 was good.
If the aux battery was fully charge with N3 bad, it would have been posible to start and drive but failures would soon arise.

I am the owner of a 2020 with the OEM batteries. With a late 2019 build date, that puts my batteries at 5 plus years.
Sponsored

 
OP
OP

darkstar13

Active Member
First Name
Ray
Joined
Sep 7, 2020
Threads
1
Messages
40
Reaction score
11
Location
Helena, MT
Vehicle(s)
2025 Jeep Rubi Gladiator
Occupation
Old Veteran
I’ll add that I am not trying to be difficult, but as an owner of a 22 with oem batteries, the neg+f42 aux delete at the time of new main purchase is on my own radar in the near future. Beyond being careful with those neg cables and taking off the correct one for your model year, should a prospective performer of this aux delete be aware of any other likely sources of shorts?
I am in parallel as I have a 2020. I made the mistake of not connecting the AUX + to the Main +in my initial AUX delete attempts. I did not want to take the chance of shorting out the "N" array by pulling the AUX + thru that narrow hole ( plus is is attached to another cable) to facilitate connecting it to the MAIN +. Upon doing that my vehicle started and runs fine for the time being. No codes, no lights flashing, windshield wipers going very slow, unable to shut down and my ESS is off. I did fail to initially check voltages as Lost1wing pointed out at the "N" terminals. There is a lot of confusing info coming from different ways to delete. I think I am ok now thanks to the much valued and appreciated straight forward help I have received from all.
 
OP
OP

darkstar13

Active Member
First Name
Ray
Joined
Sep 7, 2020
Threads
1
Messages
40
Reaction score
11
Location
Helena, MT
Vehicle(s)
2025 Jeep Rubi Gladiator
Occupation
Old Veteran
Start with taking the ground off at either the fender or at the top plate on the main battery neg. If you take it off at the fender, you know you have both batteries disconnected. If you take it off at the top plate on the main neg, it is possible to take off the aux neg cable. Now you are left with holding it out of the way while you take the other cable off. No big deal, just be careful. If you leave these grounds unprotected with either positive cables still connected and touch them to ground, you may see some sparks. That would just be the car trying to energize the circuits. Leaving the grounds connected to the fender and at the top plate and reming the assy from the main neg post leaves you open to the fuse array going bad if a positive cable touches ground. Usually the 150amp N3. Now depending on the state of the Aux battery, you will see different indications of the failed fuse. A dead or very low voltage would give you what I believe the OP had. He correctedthe issue by moving the positive aux cable to the main positive. He shouldn't have to do that if the pcr was deactivated (f42) and N3 was good.
If the aux battery was fully charge with N3 bad, it would have been posible to start and drive but failures would soon arise.
I do not want any unforeseen failures awaiting me. I have everything extremely well wrapped and tied. I did not pull the AUX + cable thru. I made another 6 gauge extension, connected it at the bottom in the original AUX battery box and ran it back thru (while disconnected) to the Main +. I want to clarify that I had NO AUX Battery connected then or now. The reason I say that is because there was/is no AUX to talk to the N3. Please correct me to avoid future failure. Thanks again.
 

Lost1wing

Well-Known Member
First Name
Tim
Joined
Dec 22, 2020
Threads
24
Messages
2,606
Reaction score
2,845
Location
West Georgia
Vehicle(s)
2020 Jeep Gladiator Rubicon
Occupation
Retired AMT
I am in parallel as I have a 2020. I made the mistake of not connecting the AUX + to the Main +in my initial AUX delete attempts. I did not want to take the chance of shorting out the "N" array by pulling the AUX + thru that narrow hole ( plus is is attached to another cable) to facilitate connecting it to the MAIN +. Upon doing that my vehicle started and runs fine for the time being. No codes, no lights flashing, windshield wipers going very slow, unable to shut down and my ESS is off. I did fail to initially check voltages as Lost1wing pointed out at the "N" terminals. There is a lot of confusing info coming from different ways to delete. I think I am ok now thanks to the much valued and appreciated straight forward help I have received from all.
You do not have to remove the aux battery to do the delete. Isolating the aux negative and pulling f42 is all that is needed.

Removing the Aux battery will need the aux positive connected to the main positive, like I believe is the way you have it now. Rhis way I believe f42 does not need to be pulled because whe the pcr opens to do the test, it will see the main battery and all will be happy.

If for some reason you only disconnected and removed the aux battery without relocating the aux positive, I can see you have a similar result as the N3 being blown.
 

sharpsicle

Well-Known Member
Joined
Apr 29, 2021
Threads
22
Messages
2,760
Reaction score
6,255
Location
Tampa, FL / Milwaukee, WI
Vehicle(s)
2020 Gladiator Overland, 2002 VTX1800
My two thoughts after reading through all this:

  1. With how you have it set up now, make sure you disable the ESS system at every start, or have something that remembers the last state for you. You do not want ESS active on just the main battery, as the voltage drop from a start event may cause the computers to reboot, leaving you stuck in the road. This is the whole point of the aux battery's existence.
  2. This really seemed like a lot of runaround just to not put in a new aux battery, but that's just me...
 

Sponsored

OP
OP

darkstar13

Active Member
First Name
Ray
Joined
Sep 7, 2020
Threads
1
Messages
40
Reaction score
11
Location
Helena, MT
Vehicle(s)
2025 Jeep Rubi Gladiator
Occupation
Old Veteran
You do not have to remove the aux battery to do the delete. Isolating the aux negative and pulling f42 is all that is needed.

Removing the Aux battery will need the aux positive connected to the main positive, like I believe is the way you have it now. Rhis way I believe f42 does not need to be pulled because whe the pcr opens to do the test, it will see the main battery and all will be happy.

If for some reason you only disconnected and removed the aux battery without relocating the aux positive, I can see you have a similar result as the N3 being blown.
Do you think I should put the f42 back at this point? I AM worried that the N3 is blown. I definitely have the AUX + connected to the MAIN +
 
OP
OP

darkstar13

Active Member
First Name
Ray
Joined
Sep 7, 2020
Threads
1
Messages
40
Reaction score
11
Location
Helena, MT
Vehicle(s)
2025 Jeep Rubi Gladiator
Occupation
Old Veteran
My two thoughts after reading through all this:

  1. With how you have it set up now, make sure you disable the ESS system at every start, or have something that remembers the last state for you. You do not want ESS active on just the main battery, as the voltage drop from a start event may cause the computers to reboot, leaving you stuck in the road. This is the whole point of the aux battery's existence.
  2. This really seemed like a lot of runaround just to not put in a new aux battery, but that's just me...
I have read about so many, many issues about this that I was going to consider the Geniys system, just to get the bigger 2nd battery. And not have to worry about it when overlanding. I agree with you about my lack of knowledge. I have always had dual batteries in my 2012 JK and never had any issues. So you are telling me to be sure and turn off the ESS each and every start. I was under the impression that with the F42 pulled that was not an issue. Please correct me Thank you
 

Lost1wing

Well-Known Member
First Name
Tim
Joined
Dec 22, 2020
Threads
24
Messages
2,606
Reaction score
2,845
Location
West Georgia
Vehicle(s)
2020 Jeep Gladiator Rubicon
Occupation
Retired AMT
Do you think I should put the f42 back at this point? I AM worried that the N3 is blown. I definitely have the AUX + connected to the MAIN +
You essentially just jumpered N1 to N2. That is what other have done and eliminated cables being wrapped up.

When the computer commands the pcr to open, it wil not see if the pcr actially opened. It will assume it opened and look at the voltage. It will see your main battery voltage because that is where your aux positive is. If you leave f42 in, the pcr will open and still see the main battery voltage because you moved the cable to the main positive post.
 
OP
OP

darkstar13

Active Member
First Name
Ray
Joined
Sep 7, 2020
Threads
1
Messages
40
Reaction score
11
Location
Helena, MT
Vehicle(s)
2025 Jeep Rubi Gladiator
Occupation
Old Veteran
You essentially just jumpered N1 to N2. That is what other have done and eliminated cables being wrapped up.

When the computer commands the pcr to open, it wil not see if the pcr actially opened. It will assume it opened and look at the voltage. It will see your main battery voltage because that is where your aux positive is. If you leave f42 in, the pcr will open and still see the main battery voltage because you moved the cable to the main positive post.
I am taking that as you don't have a problem with this method then. Is there a way I can still check the N3 for a blown condition at this point without undoing everything. Let me add I am not trying to waste all of you folks time with this,. I do appreciate your help. I am just a little slower
 

Lost1wing

Well-Known Member
First Name
Tim
Joined
Dec 22, 2020
Threads
24
Messages
2,606
Reaction score
2,845
Location
West Georgia
Vehicle(s)
2020 Jeep Gladiator Rubicon
Occupation
Retired AMT
My two thoughts after reading through all this:

  1. With how you have it set up now, make sure you disable the ESS system at every start, or have something that remembers the last state for you. You do not want ESS active on just the main battery, as the voltage drop from a start event may cause the computers to reboot, leaving you stuck in the road. This is the whole point of the aux battery's existence.
  2. This really seemed like a lot of runaround just to not put in a new aux battery, but that's just me...
Not to confuse anyone on the subject of ESS, sharpsicle you are correct on the purpose of the aux battery. I think there was some discussion on when the pcr actually opens and how long it remains open. From what I remember reading, is that the pcr is actually closed during an ess start letting the aux assist the main.
 

Sponsored

Lost1wing

Well-Known Member
First Name
Tim
Joined
Dec 22, 2020
Threads
24
Messages
2,606
Reaction score
2,845
Location
West Georgia
Vehicle(s)
2020 Jeep Gladiator Rubicon
Occupation
Retired AMT
I am taking that as you don't have a problem with this method then. Is there a way I can still check the N3 for a blown condition at this point without undoing everything. Let me add I am not trying to waste all of you folks time with this,. I do appreciate your help. I am just a little slower
You could remove the aux + from the main + and check voltage at N3. If you don't see battery voltage I would assume it is bad. If you see battery voltage I would assume it is good. The way you have it doesn't really care about the pcr anymore. N1 and N2 tied together took care of that issue.

I would still look at ESS defeat tool. So far you only eliminate that extra power from the aux. Repeated ESS events could get you into trouble down the road in stop and go traffic.
 

Lost1wing

Well-Known Member
First Name
Tim
Joined
Dec 22, 2020
Threads
24
Messages
2,606
Reaction score
2,845
Location
West Georgia
Vehicle(s)
2020 Jeep Gladiator Rubicon
Occupation
Retired AMT
I have read about so many, many issues about this that I was going to consider the Geniys system, just to get the bigger 2nd battery. And not have to worry about it when overlanding. I agree with you about my lack of knowledge. I have always had dual batteries in my 2012 JK and never had any issues. So you are telling me to be sure and turn off the ESS each and every start. I was under the impression that with the F42 pulled that was not an issue. Please correct me Thank you
Excuse me stepping in. F42 only prevents the pcr from opening so that when the computer commands a test, it will compare the main battery voltage to the main battery voltage, tricking the computer that the Aux is fine. The only thing tieing this to ESS is that for ESS to function both batteries must be good. Ess will still function if left on. Defeaters like Tazer are not really defeaters. They only leave the switch in it's last position. Other tricks such as hood switches, don't let ESS work ( prerequisite hood closed).
 
OP
OP

darkstar13

Active Member
First Name
Ray
Joined
Sep 7, 2020
Threads
1
Messages
40
Reaction score
11
Location
Helena, MT
Vehicle(s)
2025 Jeep Rubi Gladiator
Occupation
Old Veteran
Excuse me stepping in. F42 only prevents the pcr from opening so that when the computer commands a test, it will compare the main battery voltage to the main battery voltage, tricking the computer that the Aux is fine. The only thing tieing this to ESS is that for ESS to function both batteries must be good. Ess will still function if left on. Defeaters like Tazer are not really defeaters. They only leave the switch in it's last position. Other tricks such as hood switches, don't let ESS work ( prerequisite hood closed).
I notice you have a a 2020 as well. Have you ever run into any of this type of problem?
 

Lost1wing

Well-Known Member
First Name
Tim
Joined
Dec 22, 2020
Threads
24
Messages
2,606
Reaction score
2,845
Location
West Georgia
Vehicle(s)
2020 Jeep Gladiator Rubicon
Occupation
Retired AMT
I notice you have a a 2020 as well. Have you ever run into any of this type of problem?
I haven't really had any problems.

When I first picked up the Gladiator, I started collecting a few upgrade items, winch aux switches ( aftermarket), and freezer. I started with the S-Tech aux switches. I disconnected the main battery connection at the post. I started working o the install under the hood. I made a bracket for a circuit breaker. This took some time. It was the next day when I finished the install. I hooked up the main neg on the post and jumped in the drivers seat. Everything looked and acted normal until I went to start. I got flicker lights and a no crank. Second attempt was the same.

Found the Gladiator Forum!

Now realizing that I had two batteries and that I completely killed the aux, I separated both negatives and removed the geound at the fender. I then charged the aux battery over night and surprisingly it came back to life and tested good. I then charged the main battery. I had a few weeks of the battery charging message.

Back to the Gladiator Forum!

There I found Mr. Bill and ShadowsPapa's threads on ESS. Others contributed to the thread as well but those two I can recall .

I charged both batteries now with an AGM charger and reset the IBS. I haven't had any issues since. I do notice that if the JT sits for over a week my ESS battery charging message will remain on for a longer period of time. When that happens I plug in my NOCO charger.
 

Jaxmax

Well-Known Member
First Name
Jack
Joined
Jun 28, 2020
Threads
54
Messages
2,856
Reaction score
4,637
Location
Bally, Pa.
Vehicle(s)
Jeeps....... 2021 Mojave , 2019 Wrangler
Occupation
Electrical Manager
Leave F42 fuse pulled for now. Do you have a volt meter and are all the wires off N-3 now? If no wire on there put meter between N-3 and ground wires on fender and you get no reading you probably have a blown fuse, having N-1 which goes to senisitive electronics unfused very long is not a good idea.
You need to be aware of the simple circuit involved with Aux battery and the PCR , N-3 takes fused main battery power down to the PCR to one side, on the other side of this "switch" is terminated N-1 which feeds the electronics and also the Aux battery positive, so during a s ESS event the PCR opens disconnecting main battery power from electronics but Aux battery is still connected. You could have just pulled the wires off N-1 and N-3 and PUT A JUMPER BETWEEN N-1 AND N-3 if your fuse is good, instead of going back down to the battery with another wire. Don't put the jumper between N-1 and N-2 , I think you are getting it that it's unfused then. I would check carefully to see if you have a blown fuse that is an expensive repair I believe.....Jack
Sponsored

 
Last edited:
 







Top