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2017 Chevy Bolt LT
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Faulty OBD 2 adapter?
Yeah, maybe that's what I'm seeing too. MyGreenVolt is just... wrong... to me. The readings are never, ever the same as with my bluetooth OBD/apps, which always match up with each other. I think my ancient WiFi OBD might be bunk at this point or else MGV just isn't trustworthy. Either way I'm back to OBD Fusion and staying there for it's superb logging.
 

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Something is very odd. None of your voltage values make sense. The MGV app is too low, and the TP max and average can't be the same. Faulty OBD 2 adapter?
All of the other values in Torque look correct. I looked at one earlier post in this thread that showed someone else's ave and high to be the same also.
 

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MGV is showing 30mv from max to low. Torque is showing 20mv from ave to low. And max and ave the same. Maybe my pid for max cell is corrupt and showing the same as ave. Although if I sit and watch the live values, sometimes they differ and can actually show ave as higher than max. That is the first time I started MGV and didn't pay.
 

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12/16 build, 2017, white LT
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Well, today was an interesting day. I have been logging cell voltage delta since 2018 when we got Torque Pro, and Telek's PIDs. The same three cells were always highest, and the same three cells were always lowest. Total cell voltage delta from highest to lowest cell, from 100% SoC down to 5% SoC was never more than 0.025 volts. The last time I grabbed a screen shot was 02-20-22 for Torque Pro

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and 08-01-21 for MyGreenVolt.

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But I monitor them every few weeks.

Today we went on an errand. My wife was driving so I pulled up Torque Pro, and noticed it was showing cell #47 as the lowest. That never happens. So I added a gauge to see what it was showing. Yikes!

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Next I pulled up MyGreenVolt.

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I wonder if I am the first to catch a cell failing in real time? Back in 2017, a total cell delta of 0.030 volts would get you a new battery section.

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Later, they hugely increased the spread to 0.070 volts from the average cell voltage!

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This means that cell #47 is not officially crap. But you and I, and GM, know the truth.
 

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12/16 build, 2017, white LT
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I noticed you mentioned wife driving - but if data collected while driving, the 96 values are collected not all at same time. I assume you know that and will have done more checking before worrying too much.
The screen shots are all with the car at rest with everything off. Normally, while driving, it will bounce around between the three highest and lowest cells. Cell #47 is so bad now, it is always way below the others while driving, at rest, and while charging. It is toast.
 

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2017 Bolt
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The screen shots are all with the car at rest with everything off. Normally, while driving, it will bounce around between the three highest and lowest cells. Cell #47 is so bad now, it is always way below the others while driving, at rest, and while charging. It is toast.
Clear, and I did expect you were doing at-rest data collections. Recognized you from the busy TorquePro-PID-days when I was also using and learning the TorquePro and PID system, at least at a basic level. After getting my 2017's battery replaced a few months ago I did only a few new PID-data collections for the 96 cell groups and all looked fine, meaning closer voltage values than the old 60 kWh battery. Your values are for the original, un-replaced battery, I think. A new battery one would give you boost ?
 

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Your values are for the original, un-replaced battery, I think. A new battery one would give you boost ?
Yeah. Will be getting it replaced once they sort out all the software problems.

Here it is plugged in, in the garage, after charging to hilltop, and the AC chiller cooling down the battery. It is running the 4 hour diagnostic check from our last software update. Clearly, it made no attempt to balance that failing cell. You can still see the eight high, and eight low, cells we noticed as a pattern years ago, but #47 has collapsed.

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Funny/sad side note: Right after discovering the failing cell, got our August Diagnostic Report email from OnStar.

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Lithium-Ion Battery

No issues found with the lithium ion battery. They can tell if my tire is low, but the battery is a total mystery to them.
 

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2021Bolt to 2022EUV
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@GJETSON's MyGreenVolt screenshot made me realize that there is a "MyGreenVolt" android app, so I downloaded it and paid the insignificant amount to enable the cell graph. Here's mine, a 2017 Bolt, original battery, with 112K kilometers (about 70K miles):
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@GJETSON's MyGreenVolt screenshot made me realize that there is a "MyGreenVolt" android app, so I downloaded it and paid the insignificant amount to enable the cell graph. Here's mine, a 2017 Bolt, original battery, with 112K kilometers (about 70K miles):
View attachment 45520
Wonder if the max voltage variation is the same as a Volt. For a Volt the max is about 122mv, so your ok at 21mv. But this needs to be measured on the down side or low SOC level.
Exactly what mv variation will trip a code can vary from 121mv to some say as high as 300mv. This is all hearsay and not a official GM criteria.
 

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"MyGreenVolt" android app, so I downloaded it Here's mine, a 2017 Bolt, original battery, with 112K kilometers (about 70K miles):
Yup. Your cells look exactly like ours did until #47 collapsed. Notice your highest is #9, and your lowest is #67. I had gauges for my three highest and lowest cells. Notice which ones.

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Yup. Your cells look exactly like ours did until #47 collapsed. Notice your highest is #9, and your lowest is #67. I had gauges for my three highest and lowest cells. Notice which ones.
9 and 67 have always been the extremes whenever I've checked using TorquePro, and from what I've seen in various posts including yours this is pretty much standard across the fleet. It really makes me wonder why that is. Something about the cells, or something about the BMS sensors and interconnecting wiring that makes those cells look lower than usual? I could maybe understand if the limits were always in particular modules, but that they're always the exact same cells seems odd to me, particularly since they're so significantly different than the average.
 
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