[pwd847]

I have had a few instances (in winter) where my 2018 Compass wouldn't start. Neighbor came over with jump start pack and it started right up the first time. Last couple times I put a 12V 6A charge on it for an hour and it started up.

Went to Sams and bought a size 47 Duracell. Called Jeep dealer service dept and asked if changing main battery would cause issures. They said no. So I installed it. Brought Mopar battery to Advance Auto, and it tests fine. Now I wonder about the Aux battery.

I've heard about battery management systems, and charge controllers, etc... Is this Aux battery linked to the computer somehow? Like with a serial number? The dealer said yes.

Anyone know how to replace it?

Also, would be interested in a OBDII programmer to turn off the start/stop and tinker around. I did uninstall the entry level infotainment stereo and replaced with nice Kenwood touchscreen. However stock radio is in my closet so if I need to temp install it to adjust settings I can.

Thanks!

 

[H20DOG]

I have had a few instances (in winter) where my 2018 Compass wouldn't start. Neighbor came over with jump start pack and it started right up the first time. Last couple times I put a 12V 6A charge on it for an hour and it started up.

Went to Sams and bought a size 47 Duracell. Called Jeep dealer service dept and asked if changing main battery would cause issures. They said no. So I installed it. Brought Mopar battery to Advance Auto, and it tests fine. Now I wonder about the Aux battery.

I've heard about battery management systems, and charge controllers, etc... Is this Aux battery linked to the computer somehow? Like with a serial number? The dealer said yes.

Anyone know how to replace it?

Also, would be interested in a OBDII programmer to turn off the start/stop and tinker around. I did uninstall the entry level infotainment stereo and replaced with nice Kenwood touchscreen. However stock radio is in my closet so if I need to temp install it to adjust settings I can.

Thanks!

More information on your Kenwood system would be great to post in another thread. I would like to see a video of it installed and go through the screens especially the ones that goes through the idatalink Maestro interface (assuming that is the case).

 

[arudlang]

Is this Aux battery linked to the computer somehow? Like with a serial number?

Serial number?? It's just a battery. 12.x volts. Positive and negative terminals. It has no special link to anything, its a crude lead acid power storage device.

Anyone know how to replace it?

Unbolt it and bolt a new one in. Red goes to positive... black goes to negative. (sorry for the sarcasm, having a bad day here) Its not a special battery. Same as in your lawn mower if you have a rider probably. Should always change the Aux with the main battery (my opinion).

 

[pwd847]

Serial number?? It's just a battery. 12.x volts. Positive and negative terminals. It has no special link to anything, its a crude lead acid power storage device.



Unbolt it and bolt a new one in. Red goes to positive... black goes to negative. (sorry for the sarcasm, having a bad day here) Its not a special battery. Same as in your lawn mower if you have a rider probably. Should always change the Aux with the main battery (my opinion).

That's what I originally thought..."How can a battery be registered with the computer?", but the dealer says otherwise, and multiple threads I have seen across the internet say otherwise.

 

[arudlang]

I don't think that is a "thing" for FCA vehicles, not yet anyways, but hopefully someone will chime in if I'm wrong. I dug through a few Jeeps on AlfaOBD and did not see any battery replacement/reset procedures and seems like that would be a big one if it were necessary. Could have been looking in the wrong place though. If you can't find any references to it on other Jeep forums or youtube, then I don't think it applies here.

 

[pwd847]

That's a good point.

 

[Baja-D]

There are some other things that have to be disconnected to change the aux battery. Has a relay and other wire connections siting on top of the battery bracket. Need to be extremely careful you do not short anything out and get everything back together right. If you are not electrically savvy I would recommend having a technician do it.

 

[pwd847]

There are some other things that have to be disconnected to change the aux battery. Has a relay and other wire connections siting on top of the battery bracket. Need to be extremely careful you do not short anything out and get everything back together right. If you are not electrically savvy I would recommend having a technician do it.

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Yes I am aware of all of this. I suppose I'll just replace it then. Ideally I can find a better battery with more CCA.

In the future I may upgrade to a larger battery in trunk to support a couple amps and some subwoofers.

 

[pwd847]

Got my ODB MX+ today. Installed the free Mopar module, and there is definitely an intelligent battery system in there. I saw the "IBS reset flag" == FALSE. That must flip to TRUE when I remove the AUX14 battery.

 

[arudlang]

There is a unit called the "Intelligent Battery Sensor" (IBS), but AFAIK it does not need to be reset when the aux battery is changed. There are tons and tons and tons of battery changing videos and resources online for Jeeps, many cover the Aux battery well but none of them I have seen mention any kind of reset whatsoever when swapping batteries. It wouldn't surprise me if it became a thing eventually but I just can't find any evidence for it. Just because a tool or utility has the ability to reset the IBS does not indicate that it is a necessary procedure for a battery change. My OBD tools can reset gobs and gobs of things around the car, sometimes just being able to reset something is an option for when its misbehaving, or when the entire part is being replaced. Please substantiate with further evidence if you can.

 

[Bar&shield]

We've been through a few batteries.
Going back to the dealership next week I'll ask them.