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Hi there, purchased a 2012 Volt about a week ago. Very cool car, it's got everything but navigation. 77,000 miles lifetime 110 mpg. Just had the recall software update done and averaging about 9.4 kwh used per drive. Had the low propulsion power message pop up once same day I got it but not since, scared the **** out of me. But the car had sat along time fully charged and hadn't been driven much.
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Congratulations on your purchase of a 2012 Volt!

I am still fascinated by the 2012 Volt I’ve been driving for over 8 years now. I’m retired, so I rarely drive beyond battery range. That means I arrive home at the end of the day, plug into the wall, and by the next morning without any additional effort on my part, the "fuel elves" have refilled my battery and I have a "full tank" when I drive off the next day!

I myself had the cell balancing procedure done last November on my 2012 Volt. Normally I plug in every day when I get home, even if I haven’t used up much of the battery. After getting the cell balance work done, however, I drove my Volt through 11 full charge/full depletion cycles (even if it took a couple of days to drive far enough to deplete the battery), so that the Battery State Estimate Algorithm could calibrate itself using data gathered from throughout the entire "usable window" of power (read more about that in moderator Steverino’s kWh Used vs. Battery Degradation FAQ: (kWh Used vs. Battery Degradation FAQ).

I recommend you do the same - drive your Volt through a few full charge/full depletion cycles to help calibrate the algorithm used to estimate when it’s time to "switch to gas." As I drove through those cycles, I used an OBD reader and the mygreenvolt app to view the raw state of charge at full charge when I unplugged from the wall, and the raw SOC at the point where the system switched to gas. The Wikipedia page for the Gen 1 Volt says the usable window is 65% of full battery capacity, and I was able to determine over 11 cycles that my "usable window" met that expectation. I was averaging ~65.35%, with an average ~9.39 kWh Used for a full cycle (this was in Dec/Jan - over the years my numbers have ranged from 9.2 to 10.7, with the lowest readings in the colder months). Using those numbers, math says my 2012 Volt’s full battery capacity is ~90% of new after 8+ years of driving (warranty specs say 70% or better).

For more information on what the cell balancing procedure does, I repost this item that forum member JuneBug posted in another thread that he obtained from the Facebook Volt Owners forum:

"Jaryd Carvell->Hi friendly neighborhood Volt tech here! As I have tried to explain to so many people in this group. The recall (GM Program #:N172130462 Issued: Mar 28, 2019) is to correct your vehicle from improperly balancing the cells over time. The balance of those cells is part of what is used to calculate the GOM. When they reprogram the module 2 things happen. The vehicle starts to properly balancing the cells again, and the battery capacity learned values are reset. Over the course of multiple charge/discharge cycles the cells properly balance, and then the module relearns the capacity and the GOM adjusts accordingly. If your GOM goes up or down it means that the car had not been properly balancing the cells for quite some time. This process happens much slower without full discharge/charge cycles and so some people the adjustments happen much quicker than others. Also not all vehicles have the same cell imbalance. Even with the bad software some vehicles were staying close to properly balanced and others were quite a bit off. If yours was one that was close to correct, not much will change after the recall. If your cell balance was off, the more it's going to change after the recall. This is why some people noticed almost no change and others have had a change in the GOM. This is also why some people have seen the change quickly and some it took a while. Complete discharge/complete charge cycles will accelerate this learning process. Oh and one more thing, the 2013-2015 volts have 9 battery temp sensors but really only need 6. There is also software included in the recall that allows the vehicle to ignore up to 3 of the redundant temp sensors if they fail, rather than having to replace them. So there are multiple reasons to have this recall performed."
 

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Got 40 miles today, it was about 95F but I drove it on the backroads mainly with no AC. Got the rpp again the other night after letting set for a few hours, it went off after 30 seconds or so. I've been driving daily to reset the battery balance.
 
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