Auto stop-start auto-disabled

[Malachi]

My primary battery died. It gave us 4.5 years of service, so I am OK with that. I've heard that the AUX battery can contribute to this and that you should change both out, but at $~280 for the H7 I needed to gamble that that would be enough.

New battery in, Jeep runs happily - I didn't realize it was "hard starting" but it was, it starts MUCH more smoothly than before. Great!

With that stage set, as the title indicates, I do get a warning light indicating auto stop-start is basically offline. Now, in fact, I love this. I have never been a fan of auto stop-start. But I have to ask, is this a symptom of another issue? Should I fix this?

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[The Last Cowboy]

Since you're not going to replace the aux battery, it will quickly draw down your new H7. The quick and easy solution is to remove the ground cable from the aux at the main battery terminal making sure to tape it well over the exposed metal on the end of the cable, then pull fuse f42. Now, the aux battery will be permanently removed from the circuit, unless you want to reconnect it for some reason.

 

[DaltonGang]

Since you're not going to replace the aux battery, it will quickly draw down your new H7. The quick and easy solution is to remove the ground cable from the aux at the main battery terminal making sure to tape it well over the exposed metal on the end of the cable, then pull fuse f42. Now, the aux battery will be permanently removed from the circuit, unless you want to reconnect it for some reason.

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What he said

 

[Ratbert]

Yes, it's a symptom of another issue.

You have four options:

1. Replace the aux.
2. Bypass the aux, leaving it in place.
3. Bypass and remove the aux.
4. Do nothing this iteration, resulting in trashing your new main and starting again with these four options. Don't choose this one.

 

[Malachi]

Thank you everyone for your feedback. If it's not too heinous I think I'll try changing out the aux battery myself

EDIT:

I remember reading back in the day it was a tedious process. Watching the videos yeah I think I'm gonna hire someone to do change it out.

 

[Ratbert]

Thank you everyone for your feedback. If it's not too heinous I think I'll try changing out the aux battery myself

EDIT:

I remember reading back in the day it was a tedious process. Watching the videos yeah I think I'm gonna hire someone to do change it out.

Maybe you have an EcoDiesel and it's simple to get to?

If not, many here advise to go through the wheel well and not risk damaging parts of the electrical system by going from above.

 

[The Last Cowboy]

Thank you everyone for your feedback. If it's not too heinous I think I'll try changing out the aux battery myself

EDIT:

I remember reading back in the day it was a tedious process. Watching the videos yeah I think I'm gonna hire someone to do change it out.

I’ve never heard of a positive outcome from charging the aux.

You don't have to remove it, just disconnect it and pull a fuse.

You’ve convinced yourself that the simple solution is more complicated than attempting to maintain the complex, failure prone OEM setup.

 

[Malachi]

I’ve never heard of a positive outcome from charging the aux.

You don't have to remove it, just disconnect it and pull a fuse.

You’ve convinced yourself that the simple solution is more complicated than attempting to maintain the complex, failure prone OEM setup.

Incorrect. I am assessing my options. The aux battery serves a purpose. Your suggestion negates some OEM abilities. That's fine for you, I'll decide for myself if it's fine for me. I will agree it's an overly complicated arrangement.

In the short term in fact I will bypass the AUX so that I don't immediately wipe out the new main battery.

 

[alphawolff]

Incorrect. I am assessing my options. The aux battery serves a purpose. Your suggestion negates some OEM abilities. That's fine for you, I'll decide for myself if it's fine for me. I will agree it's an overly complicated arrangement.

In the short term in fact I will bypass the AUX so that I don't immediately wipe out the new main battery.

The aux is used during stop/start events to preserve complete voltage integrity of the interior electronics during the stop/start event and eventual re-start of the engine. Without the isolated circuit, the interior electronics could power cycle during the re-start depending on the SOH of the primary. That is the OEM design function.

If you delete the aux battery, it is assumed you are also not using the stop/start functionality. You should not use stop/start regardless of which solution you pick.

 

[The Last Cowboy]

You can lead a horse to water…

 

[Malachi]

There's some good information here, thank you.
There's also some unnecessary attitude. Can we chuck that already.

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