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louv

louv

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It’s odd that the 12volt battery doesn’t have cutoff at min cell voltage
To keep from killing the battery by going completely depleted ??
oops not sure you can do that with a LiFe
That is the reported “bug” in the firmware (BMS) of the original 12v battery: It was not reading current correctly, so it allowed itself to be drawn down too far. The new replacement 12v has better firmware. Hopefully.
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My car now has ALL THE CAMPAIGNS!!!

WLE3 - 12v vehicle battery with updated firmware.
WLD0 - Replace hi-voltage line from HV distributor to E-box.
WLF2 - Check & Replace seat belt latches.
WLH5 - Drain plug adjustment (AC condensate drain).

Now I can re-test and see if I can cause the car to drain the 12v battery. Cross your fingers and wish me luck!
I'm assuming your test went okay, correct Don?

Chuck J
 

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That is the reported “bug” in the firmware (BMS) of the original 12v battery: It was not reading current correctly, so it allowed itself to be drawn down too far. The new replacement 12v has better firmware. Hopefully.
Should be an easy fix
 
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louv

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Should be an easy fix
Yes...
(for just the cars in the USA)
1) manufacturer an extra 578 new batteries with correct non-updateable firmware. Write repair orders. Translate & localize.
2) ship them across the Atlantic (by sea, since air shipping is highly restricted)
3) truck them to dealerships (see #2)
4) have customers bring in their cars
5) replace battery in car with part V04-015-001-BA (Shop time: 163 units)
6) Recall all previous battery inventory part 9J1-915-105-EY (ship by ground and sea)

Easy. :cool:
 


B777

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Yes...
(for just the cars in the USA)
1) manufacturer an extra 578 new batteries with correct non-updateable firmware. Write repair orders. Translate & localize.
2) ship them across the Atlantic (by sea, since air shipping is highly restricted)
3) truck them to dealerships (see #2)
4) have customers bring in their cars
5) replace battery in car with part V04-015-001-BA (Shop time: 163 units)
6) Recall all previous battery inventory part 9J1-915-105-EY (ship by ground and sea)

Easy. :cool:
I meant the software fix
But haven’t done any recent research on liFe battery I thought cutoff was based
Yes...
(for just the cars in the USA)
1) manufacturer an extra 578 new batteries with correct non-updateable firmware. Write repair orders. Translate & localize.
2) ship them across the Atlantic (by sea, since air shipping is highly restricted)
3) truck them to dealerships (see #2)
4) have customers bring in their cars
5) replace battery in car with part V04-015-001-BA (Shop time: 163 units)
6) Recall all previous battery inventory part 9J1-915-105-EY (ship by ground and sea)

Easy. :cool:
just meant the software fix
But maybe not
 
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louv

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I meant the software fix
But haven’t done any recent research on liFe battery I thought cutoff was based

just meant the software fix
But maybe not
I think you are correct. The actual software fix was probably changing the value of a constant.

I was being a little silly, because if they had considered that they just might possibly have bugs in the battery’s firmware, then this would have been easier (read: cheaper) to fix.

Maybe it was arrogance in coding, “we are sure this is right. We couldn’t possibly be wrong.” Or maybe it is possible to update the firmware, but it requires some very complex tools (either in disassembly of the battery, or in re-calibrating the battery afterwards, or both) and it cost less to replace them this way than to equip all service departments with yet more very expensive tools.
 


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louv

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Glad to hear! If @louv can’t kill it, this bug may have finally been licked! ✔
Ha! I’ve only tried twice. I’ll keep trying... for Science.
 

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I think you are correct. The actual software fix was probably changing the value of a constant.

I was being a little silly, because if they had considered that they just might possibly have bugs in the battery’s firmware, then this would have been easier (read: cheaper) to fix.

Maybe it was arrogance in coding, “we are sure this is right. We couldn’t possibly be wrong.” Or maybe it is possible to update the firmware, but it requires some very complex tools (either in disassembly of the battery, or in re-calibrating the battery afterwards, or both) and it cost less to replace them this way than to equip all service departments with yet more very expensive tools.
Ha! I’ve only tried twice. I’ll keep trying... for Science.
the discharge curve on a LIFe battery

Porsche Taycan Don Breaks His Taycan - The Saga of the 12v Battery A9975942-2E69-40BC-941E-0A782E692B1D
 
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louv

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the discharge curve on a LIFe battery

A9975942-2E69-40BC-941E-0A782E692B1D.jpeg
Yes. (Mansplaining for the benefit of those curious but unfamiliar with battery tech)...

Because the discharge plot of Voltage isn’t linear with respect to remaining capacity (as is the case with lead acid batteries) capacity must be calculated with a different method. So the BMS (battery management system) measures the accumulated current that has gone in and out.
 

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Yes. (Mansplaining for the benefit of those curious but unfamiliar with battery tech)...

Because the discharge plot of Voltage isn’t linear with respect to remaining capacity (as is the case with lead acid batteries) capacity must be calculated with a different method. So the BMS (battery management system) measures the accumulated current that has gone in and out.
 

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So does everyone think this issue is resolved now, or do people still need to buy a 12v battery charger/conditioner?
 

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So does everyone think this issue is resolved now, or do people still need to buy a 12v battery charger/conditioner?
Well just this weekend somehow I was able to kill mine. Had the car charging on a Profile to 80%. It stopped at 80% according to Connect app. A day later I went to the car and totally dead. Pulled on the cord to disconnect the charger plug. Then went to AutoZone to get NOCO Boost HD GB70 lithium battery jump starter. Will attempt the wake up with it and see if the 800V battery will then charge up the 12V. Not sure why this happened to begin with. The only thing that I remember is that during charging (I think) the Connect app asked me if I wanted to turn on the Bluetooth to have the app connect to the car automatically when approaching it. Naturally I said sure. So I don’t know if that was the cause. I have the updated software and my 12V battery was not part of the replacement campaign.
 

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Seems like it's proven that any use of the Connect app after the initial handshake is risky. I never use mine.

Chuck J
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