DIY How-to: Take the Aux Battery Offline

[Lunentucker]

OK this is a rant but honestly two years of life for a battery that is essentially inaccessible is ridiculous. And the fact that you don't know when it is failing makes it all the worst.

I agree 100%. It's been said that Jeep OEM batteries are poor quality, but when you dig into it you find that there are really only a handful of battery manufacturers out there, and it's unlikely that Mopar has their own battery factory.
I think it's more of a design issue and the vehicles seem to have some electrical "leaks" that draw power when the vehicle is off.

Heck, our 2019 Subaru routinely does self-diagnostics while it's off, and I can even hear the fuel pump running when it's doing that, and it still has the OEM battery and going strong.

If the AUX battery was easier to access I would have no problems with leaving in the game.

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[Lunentucker]

One more note on this.
I don't have a Tazer, so I don't know a power loss might effect any changes that have been made with one. My tire size and TPMS thresholds were changed with my ECRI, so I'll have to check on those and see if the settings remained. I think they likely will be OK.

 

[sharpsicle]

OK this is a rant but honestly two years of life for a battery that is essentially inaccessible is ridiculous. And the fact that you don't know when it is failing makes it all the worst.

If you pay attention to your truck, you will know when it's having an issue with either of the batteries. The truck does a test every fresh start. It then will exhibit signs or warnings of a battery issue, such as ESS never engaging saying 'not ready - battery charging' or showing warnings about AUX switches not being available due to battery levels. Problem is most people are just ignoring these things and then act surprised when it finally gives out.

Totally agree though that the lifespan of the original batteries is crap. But if you get a good battery in there, the system works just fine.

 

[Cburd61]

Both my batteries lasted up until the day before my 3 years were up. They were replaced the day we bought it by the dealer, due to it not wanting to crank over when we were ready to leave, after signing the paperwork. We had been getting the ESS not ready for about 6 months before they went dead. Luckily, it was sitting in my driveway when it happened. I went ahead and replaced both out of pocket, as they couldn’t get me in for almost 2 weeks, and I needed my vehicle. I plan on deleting the aux battery when the time comes.

 

[Lunentucker]

I’ll probably do this when the batteries die. No need to mess with it now as I’m already in the habit of hitting the ESS button after start up

Having ESS turned off may help some. I habitually disabled it before and have had no issues to date.

 

[smlobx]

This should be made a Sticky!

One question, now that you’ve disconnected the auxiliary battery did you just remove it?

 

[brianinca]

This simply isn't true.

My initial "diagnostic" was the 8.4" UConnect rebooting itself. I waited long enough to replace the pony battery the main battery was damaged. Still no indication of a problem from the system diagnostics.

I'd replaced the pony and left my truck at the airport for five days, had to patiently use a jumper box to get started and get home. Main battery (OEM) was damaged and dead.

The replacement pony lasted less than a year, replaced under warranty from O'Reilly's, but my new bigger Group 94R battery is still going strong.

Diagnostics don't do the job when the big battery camouflages the failing pony battery. Wish that they did, but provably they don't.

If you pay attention to your truck, you will know when it's having an issue with either of the batteries. The truck does a test every fresh start. It then will exhibit signs or warnings of a battery issue, such as ESS never engaging saying 'not ready - battery charging' or showing warnings about AUX switches not being available due to battery levels. Problem is most people are just ignoring these things and then act surprised when it finally gives out.

Totally agree though that the lifespan of the original batteries is crap. But if you get a good battery in there, the system works just fine.

 

[brianinca]

I left it in place, may take it out at some point but didn't see any immediate need. I can do it fast enough now, having had practice, but, meh?

This should be made a Sticky!

One question, now that you’ve disconnected the auxiliary battery did you just remove it?

 

[Lunentucker]

This should be made a Sticky!

One question, now that you’ve disconnected the auxiliary battery did you just remove it?

Not yet. I may do that when the warranty is up and the weather is cooler.

 

[Lunentucker]

This simply isn't true.

My initial "diagnostic" was the 8.4" UConnect rebooting itself. I waited long enough to replace the pony battery the main battery was damaged. Still no indication of a problem from the system diagnostics.

I'd replaced the pony and left my truck at the airport for five days, had to patiently use a jumper box to get started and get home. Main battery (OEM) was damaged and dead.

The replacement pony lasted less than a year, replaced under warranty from O'Reilly's, but my new bigger Group 94R battery is still going strong.

Diagnostics don't do the job when the big battery camouflages the failing pony battery. Wish that they did, but provably they don't.

I have seen numerous similar accounts that mirror your experiences. I'd rather deal with it on my terms and timeline than leave it up to fate.

 

[Lunentucker]

Here's what I meant by subscriptions and themes after 24 hours.
Yesterday I didn't have Off Road Pages or Travel Link. Probably some others too, but I use those the most.

Today everything's back.

 

[legacy_etu]

So I take it when removing the aux, battery one should always deactivate the SS system? Is it possible to set the SS system button to latch and remember its last setting? I was able to latch the button on my Supra thru the use of Bimmercode. I assume I can do this too thru Alfa OBD or jscan or tazer.

Ill be happy to dump this battery and get some of the weight out of this thing, not to mention eliminating a potential trouble spot.

 

[Lunentucker]

So I take it when removing the aux, battery one should always deactivate the SS system? Is it possible to set the SS system button to latch and remember its last setting? I was able to latch the button on my Supra thru the use of Bimmercode. I assume I can do this too thru Alfa OBD or jscan or tazer.

Ill be happy to dump this battery and get some of the weight out of this thing, not to mention eliminating a potential trouble spot.

The ESS system is easily deactivated with the removal of the F42 fuse. No further programming or tricks are needed. If I press the dash button the light on the button comes on. That's it. It's already off.

 

[legacy_etu]

The ESS system is easily deactivated with the removal of the F42 fuse. No further programming or tricks are needed. If I press the dash button the light on the button comes on. That's it. It's already off.

Ah, got it. That’s even better.

 

[Oilburner]

The ESS system is easily deactivated with the removal of the F42 fuse. No further programming or tricks are needed. If I press the dash button the light on the button comes on. That's it. It's already off.

If your small battery is starting to go bad & you pull that fuse, will it disconnect the small battery from the system (as if you pulled the ground cable)?

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