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Other than the Batt Res PID, which isn't working for some reason, everything else is amazingly good. So something else is going on. Maybe GM has a new problem with the new packs.
I'm pretty sure I've never seen a different value in Batt Res. I wonder if I need to update the PID list or something. What values are considered "nominal" there?
 

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I'm pretty sure I've never seen a different value in Batt Res. I wonder if I need to update the PID list or something. What values are considered "nominal" there?
Telek has only had the PID available for a little while. I have seen values from 93.0 to 147.5

not balancing 2.jpg

The first mention of it that I saw was from BlackBolt in 2017. He saw 122.5

 

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Great. I charged to 90% last night...just to do something different. I also updated to the latest list from Telek. Now the Ah number reads 167.7 - down 1 Ah from yesterday. What should I do to verify this is a real thing? Run down to "empty" and charge to 100?
 

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Great. I charged to 90% last night...just to do something different. I also updated to the latest list from Telek. Now the Ah number reads 167.7 - down 1 Ah from yesterday. What should I do to verify this is a real thing? Run down to "empty" and charge to 100?
Just driving from 90% to 10% will give you a very accurate idea of your total usable capacity. The energy detail screen will show the kWh used since last charge.

Home from Peaks of Otter.jpg

0.90 - 0.10 = 0.80

XX kWh used divided by 0.80 = total usable capacity

Your current Ah reading of 167.7 Ah, should yield somewhere between 53.6 and 55.9 kWh total usable, depending on whether we use Wesley's low multiplier, or Telek 's original high multiplier.

If your measured capacity is in this range, this says that the Ah reading is correct, and your battery is crap.
 

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Just driving from 90% to 10% will give you a very accurate idea of your total usable capacity. The energy detail screen will show the kWh used since last charge.

View attachment 34161

0.90 - 0.10 = 0.80

XX kWh used divided by 0.80 = total usable capacity

Your current Ah reading of 167.7 Ah, should yield somewhere between 53.6 and 55.9 kWh total usable, depending on whether we use Wesley's low multiplier, or Telek 's original high multiplier.

If your measured capacity is in this range, this says that the Ah reading is correct, and your battery is crap.
I'll give that a try. That would be quite the sudden swing...21 Ah in three months. Anything else I can look at? Pack voltage at 100%, etc? So strange. For two and a half years I thought I had a pretty decent pack.
 

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Pack voltage at 100%, etc? So strange. For two and a half years I thought I had a pretty decent pack.
Pack voltage at 100% will be 399.xx volts.

not balancing 3.jpg

If the loss is real, there is definitely something going on with your battery. Our pack was a runt from day one. The highest it ever saw was 180 Ah. It now sits at 163.3 Ah. That is a drop of 9% from the theoretical max 185 Ah on a 2017. On the larger 2019 pack, a drop of 21 Ah would be 10.5%.
 

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I'll give that a try. That would be quite the sudden swing...21 Ah in three months. Anything else I can look at? Pack voltage at 100%, etc? So strange. For two and a half years I thought I had a pretty decent pack.
This is what prompted my concern about something going on since the recall. I am seeing the same quick drop in ah capacity.

FYI: my battery resistance figure is broken too. I wonder why. I have a 2019 Bolt.
 

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This is what prompted my concern about something going on since the recall. I am seeing the same quick drop in ah capacity.

FYI: my battery resistance figure is broken too. I wonder why. I have a 2019 Bolt.
That's interesting. The conventional wisdom has been that Chevy can only update the entertainment system remotely.
 

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That's interesting. The conventional wisdom has been that Chevy can only update the entertainment system remotely.
Given the various things that have gone on with Bolt batteries over the last four years, I would suspect failing batteries before I would imagine secret over-the-air updates.
 

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Given the various things that have gone on with Bolt batteries over the last four years, I would suspect failing batteries before I would imagine secret over-the-air updates.
I agree. It’s just a curiosity.

I finally grabbed some screen shots off torque pro. There are a couple PID’s I am curious about what it tells me.

question: does torque pro automatically data log everything? Or do I need to tell it what to log? thanks.

i set it up to send telek the logs per instructions on the site. However, when i email the logs to myself, they dont have any data. So i think im missing a step is why I ask.

still learning this thing.
 

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Given the various things that have gone on with Bolt batteries over the last four years, I would suspect failing batteries before I would imagine secret over-the-air updates.
Agree...the timing is probably purely coincidental. I'm running down the battery to check the capacity manually but it may take days considering my current driving habits. If the pack is actually bad, it'd be nice if it exhibited some of the telltale signs (cell discrepancies, etc). There's nearly six years left on the warranty. A new battery might be nice.
 

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I agree. It’s just a curiosity.

I finally grabbed some screen shots off torque pro. There are a couple PID’s I am curious about what it tells me.

question: does torque pro automatically data log everything? Or do I need to tell it what to log? thanks.

i set it up to send telek the logs per instructions on the site. However, when i email the logs to myself, they dont have any data. So i think im missing a step is why I ask.

still learning this thing.
You need to long press on a screen then find the PIDS you want to log. Try to decide what you want then test load a couple and then log and email like you did and using a spreadsheet you can import the files to view.
 

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You tell it what to log, and when. I have only ever logged the 96 cell voltages over a minute or so, to get a graph of cell voltages.

View attachment 34175
The OBD II can sample something like six times a minute, if you go into OBD II setting in Torque Pro and check fast sampling, or some such. So I manually told it to start a scan, and manually told it to stop sampling after about 30 seconds. You get a file which is just a long list of voltages. You load that file into a spreadsheet, and select the kind of chart you want to generate. I had it average the three samples for each cell, and created this bar graph. Not being a computer person, I sweat buckets.
 

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Great. I charged to 90% last night...just to do something different. I also updated to the latest list from Telek. Now the Ah number reads 167.7 - down 1 Ah from yesterday. What should I do to verify this is a real thing? Run down to "empty" and charge to 100?
I'm starting to get worried. Yesterday, the capacity pid showed 167.1 aH - a drop from 167.7 four days ago. Today it's at 167.0. I'm running GJETSON's suggested 90% to 10% test. I'm not there yet but at 28%, the calculation is 55.3 kWh. Maybe that number will climb as I get closer to 10% but I'm doubtful. 167.0 is a huge drop (from 189 aH) in December.

The SOC Var is low at 0.8 and I've checked the cell voltages and I don't see an issue. Batt Res is showing -128.5 mOhm; someone describe that value as "broken". Could that be the problem?

I'll continue running the test down to 10% or less. Should I get it close to empty and charge to 100% to see how much goes in? I haven't charged to 100% in ages - probably well before the recall. Could that matter somehow?

Anyway, I'm trying to decide what to do. Would Chevy give me an honest diagnostic or would they describe the sudden drop as normal degradation? If I bring it in, I'll be forced to get the recall (and 90% of 55 kWh will not work for some trips I make). Assuming these tests show an issue, I'm thinking I should wait to see what the final fix for the battery recall will be.
 

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I'm starting to get worried. Yesterday, the capacity pid showed 167.1 aH - a drop from 167.7 four days ago. Today it's at 167.0. I'm running GJETSON's suggested 90% to 10% test. I'm not there yet but at 28%, the calculation is 55.3 kWh. Maybe that number will climb as I get closer to 10% but I'm doubtful. 167.0 is a huge drop (from 189 aH) in December.

The SOC Var is low at 0.8 and I've checked the cell voltages and I don't see an issue. Batt Res is showing -128.5 mOhm; someone describe that value as "broken". Could that be the problem?

I'll continue running the test down to 10% or less. Should I get it close to empty and charge to 100% to see how much goes in? I haven't charged to 100% in ages - probably well before the recall. Could that matter somehow?

Anyway, I'm trying to decide what to do. Would Chevy give me an honest diagnostic or would they describe the sudden drop as normal degradation? If I bring it in, I'll be forced to get the recall (and 90% of 55 kWh will not work for some trips I make). Assuming these tests show an issue, I'm thinking I should wait to see what the final fix will be.
It might be worth charging to 100% at least once. There's some discussion that it may reset the Battery Management System's internal measurement somehow.
 

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Yeah that's significantly expanded from the original 0.03V from high to low. So it's 0.07V now from AVERAGE to low, or almost 5x the deviation previously permitted. Interesting. Also saw the 6.5% SoC variation in the list as warranting a module replacement.
Check out the new "standard" of excellence for section replacement. o_O

 

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Check out the new "standard" of excellence for section replacement. o_O

It's a gong show. I'm really not happy.
 
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