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Auxiliary Battery Delete Poll

Have you deleted the auxiliary battery from the electrical system pulling fuse 42


  • Total voters
    187

In3briatedPanda

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I did the genesis dual battery kit and used a taser to disable ESS. This wasn't an option so I couldn't vote lol
i plan on the genesis setup as well. i turn my ESS every morning. I have a jscan, just havent messed with it.
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Lunentucker

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Our 2019 Subaru battery is now in year 6 and doing fine.
Never had to charge it once. Sits for days with no use.
The car routinely runs self-diagnostics. I can hear it testing the fuel pump and other systems when I walk by it.
Either Subaru has a much better battery supplier or they know more about making cars.
Maybe it's both. 🤔
 

Greg_L

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As someone new to Jeep world this feature/problem/solution intrigues me on so many levels.

For one...can't you just turn this feature off? I have. Mine stays off. My JT never shuts off at stops. I also live in a location where we use AC damn near 24/7/365 so the engine shutting off at red lights never happens anyway.

Secondly...what is the symptom/problem that causes people to gut this system? This seems like a solution looking for a problem. If you don't like the auto stop/start just don't use it. I don't use my pinky toes but I'm not removing them. I admit I don't know anything though. So the auxiliary battery dies and takes out the main battery with it?

The first time I was ever in a car with stop/start I hated it, so I do get that. It reminds me of some of the totally stupid halfassed ways auto makers tried to get under emissions standards in the 80s.
 

Lunentucker

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As someone new to Jeep world this feature/problem/solution intrigues me on so many levels.

For one...can't you just turn this feature off? I have. Mine stays off. My JT never shuts off at stops. I also live in a location where we use AC damn near 24/7/365 so the engine shutting off at red lights never happens anyway.

Secondly...what is the symptom/problem that causes people to gut this system? This seems like a solution looking for a problem. If you don't like the auto stop/start just don't use it. I don't use my pinky toes but I'm not removing them. I admit I don't know anything though. So the auxiliary battery dies and takes out the main battery with it?

The first time I was ever in a car with stop/start I hated it, so I do get that. It reminds me of some of the totally stupid halfassed ways auto makers tried to get under emissions standards in the 80s.
Turning the feature off doesn't decouple the two batteries from each other.
Having them tied together in parallel for most of the time exposes each battery to issues that could be caused by one or the other failing to hold a charge.
The failing battery will continuously draw down the good battery, leaving you with no battery power to start or operate the vehicle. There's nothing in the onboard systems to warn you that it's happening.
Disconnecting the Auxiliary battery in the proper manner cuts your chances of unexpected failure in half AND it lets you see the true voltage readings of the main battery all of the time, without special tools or meters.

My GMC has an auto start-stop system, but everything runs on the one battery.

Some will argue that the auxiliary battery is there to keep your electronics stable during auto start-stop sessions. That may be the intent, but handing off the full load of sensitive electronics to a little lawnmower battery tucked away behind a fender liner is dumber than a bag of hammers.
 

Greg_L

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Turning the feature off doesn't decouple the two batteries from each other.
Having them tied together in parallel for most of the time exposes each battery to issues that could be caused by one or the other failing to hold a charge.
The failing battery will continuously draw down the good battery, leaving you with no battery power to start or operate the vehicle. There's nothing in the onboard systems to warn you that it's happening.
Disconnecting the Auxiliary battery in the proper manner cuts your chances of unexpected failure in half AND it lets you see the true voltage readings of the main battery all of the time, without special tools or meters.

My GMC has an auto start-stop system, but everything runs on the one battery.

Some will argue that the auxiliary battery is there to keep your electronics stable during auto start-stop sessions. That may be the intent, but handing off the full load of sensitive electronics to a little lawnmower battery tucked away behind a fender liner is dumber than a bag of hammers.
Ok I understand.

How much electrical "load" does the vehicle really place on a battery? Spinning an engine against compression to start does draw some amps. But everything else is or mostly digital. LEDs and screens and onboard computers don't draw amps like old school incandescents and analog switching and relays. Once a vehicle is actually running, if it has a healthy and adequate alternator then the electrical system just purrs along easily.

Seems to me that the problem is batteries. Batteries do suck these days. If I remember correctly there's really only a few companies that actually manufacture batteries and they're sold to other companies to slap their own own branding on them. Duralast, Interstae, Everstart, Exide...they all come from the same places. Maybe that's changed recently I don't know I haven't kept up.
 

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Lunentucker

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Ok I understand.

How much electrical "load" does the vehicle really place on a battery? Spinning an engine against compression to start does draw some amps. But everything else is or mostly digital. LEDs and screens and onboard computers don't draw amps like old school incandescents and analog switching and relays. Once a vehicle is actually running, if it has a healthy and adequate alternator then the electrical system just purrs along easily.

Seems to me that the problem is batteries. Batteries do suck these days. If I remember correctly there's really only a few companies that actually manufacture batteries and they're sold to other companies to slap their own own branding on them. Duralast, Interstae, Everstart, Exide...they all come from the same places. Maybe that's changed recently I don't know I haven't kept up.
Yes, there are very few battery makers in the world.
I suppose it's possible for one automaker to specify something different than others for their batteries, but it doesn't make much sense, because then the battery maker is building different tooling and using different components, which would be the exact opposite of saving costs.
The more likely explanation is that most batteries are created equal, but how they're integrated into different vehicles, and how those vehicles manage themselves and the batteries is where the differences lie.
 

gonemad

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If you don't like the auto stop/start just don't use it. I don't use my pinky toes but I'm not removing them.
Ah, but you DO use your pinky toes. I broke one of mine in about 1969. You have no idea how much they impact your routine balance.
 

DankjeeP

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You might want to chill out for a second and learn what AGM batteries are actually made of.
Maybe you missed my bigger point about putting more batteries into everything like they are going to save the planet.
 

DankjeeP

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Ok I understand.

How much electrical "load" does the vehicle really place on a battery? Spinning an engine against compression to start does draw some amps. But everything else is or mostly digital. LEDs and screens and onboard computers don't draw amps like old school incandescents and analog switching and relays. Once a vehicle is actually running, if it has a healthy and adequate alternator then the electrical system just purrs along easily.

Seems to me that the problem is batteries. Batteries do suck these days. If I remember correctly there's really only a few companies that actually manufacture batteries and they're sold to other companies to slap their own own branding on them. Duralast, Interstae, Everstart, Exide...they all come from the same places. Maybe that's changed recently I don't know I haven't kept up.
This!
I went through a few "DuraDontLast" in my other Jeep before I went to an Optima RedTop. It lasted much longer and is a much better battery. This is not as simple now because of the Aux battery fuckery. I will do the elimination mod as soon as this battery dies and upgrade to an Optima.
 

Liftr

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I just patiently waited 4 years, and replaced both batteries when I got the “Stop/Start not ready” message.
I belong in the Dull men’s club, I suppose.
 

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biodiesel

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I belong in the Dull men’s club, I suppose.
I'm in the same club. When it's time to replace the batteries, I'll buy Odyssey for both the main and auxiliary. Just like in car audio, sometimes having extra juice on hand comes in handy.
 

DankjeeP

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I'm in the same club. When it's time to replace the batteries, I'll buy Odyssey for both the main and auxiliary. Just like in car audio, sometimes having extra juice on hand comes in handy.
But you don't really have extra juice on hand, do you, it's a myth.
 

DankjeeP

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I just patiently waited 4 years, and replaced both batteries when I got the “Stop/Start not ready” message.
I belong in the Dull men’s club, I suppose.
What does it mean? Dull men’s club just curios
 

biodiesel

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But you don't really have extra juice on hand, do you, it's a myth.
It's not a myth. Since the two batteries are paralleled together, the auxiliary battery provides reserve capacity.
 
 







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