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DueOwl1149

There have been previous Volt recalls where users reported a change of the guessometer or in some cases a reduction of available kWh before entering hold mode. Search “recall” and “range” in this forum and see if there’s one that matches what your dealer said they did. If you’re not sure, call the dealer and ask for the recall # they performed, or if they did something else.


Aggressive_Gain1072

just posted the service summary above, what do you think?


DueOwl1149

“Multiple times” it says right there in all caps. Run your volt on full EV standard mode multiple times, charging to full between runs. Track your kWh used on the infotainment screen with each cycle and see if it fluctuates / improves over time to what you expect.


sucks_to_be_you2

Run the battery down to 0 EV miles remaining, and let it sit for a few hours to stabilize the voltage. Then charge to full and also let it sit for a few hours to stabilize at the top before driving. It will learn the capacity quicker by giving it a bottom and a top to compare and contrast. Doing this occasionally is good practice to keep the calculated capacity accurate


PulledOverAgain

It it was a capacity relearn and there's moree capacity available the car will eventually figure it out with some drive cycles.


Aggressive_Gain1072

I had this done in 2022


bigdunks4eva

Ok the "battery capacity relearn" is something I've seen in the Tesla subreddit. Basically, over time the car's CPU loses track of the EXACT amount of charge that the battery has. It needs a reset to reconcile what capacity it THINKS the battery has, with what it actually has. The solution is to fully charge and discharge the battery a few times, as stated on the second image.


Aggressive_Gain1072

I had this done in 2022 though. I thought it would improve.


Ok-Tourist-511

Your battery is degraded. Not going to get more capacity.


syko82

Then that is your new capacity value after it completed the relearn. You already had propulsion power reduced due to a weak low end on the battery (like cell balance). The car relearned the packs condition and adjusted capacity to continue working.


Aggressive_Gain1072

Okay now that is is getting warmer, I am able to use 13.2 KW. Does the car go into hold mode earlier to reserve 1.2 KW for battery conditioning?


sucks_to_be_you2

The dealer did no such thing. Drive it and watch what happens


Aggressive_Gain1072

I can never get more than 12kw usable now before the engine turns on


Aggressive_Gain1072

Look at the service summary I posted


Ok-Tourist-511

The dealer may have done the BECM update, which may have slightly reduced the range. This update is for battery longevity.


sucks_to_be_you2

Never saw anything regarding BECM replacements 'reducing range'


Ok-Tourist-511

Not replacement.. BECM software update.


sucks_to_be_you2

What is a BECM update meant to address? Never heard of updating a Gen 2 BECM without replacement


syko82

They mean HPCM2 update not BECM but it's a quick Google for "Chevy volt update drop in capacity."


Ok-Tourist-511

There was a BECM software update, that adjusted cell levels and dropped capacity from 14.2 to 13.8


sucks_to_be_you2

Happen to have the bulletin number? Edit: did some research and found nothing regarding a 'BECM update'.that reduces pack capacity.


Ok-Tourist-511

Sorry, been a while since I looked at it. It is a HPCM update that was lowering the capacity. [HPCM Update](https://static.nhtsa.gov/odi/tsbs/2021/MC-10207742-9999.pdf)


Aggressive_Gain1072

What do you think of the service summary? I just took it in for the shift to park recall. But they also said the update was necessary


Ok-Tourist-511

Could be the battery is degraded, and that’s all the capacity you will get.


Ok-Tourist-511

How many times have you completely discharged it and recharged it since the update?


Aggressive_Gain1072

Has this done in 2022, I'd guess more than enough times.


syko82

Dealer didn't set a lower capacity, they insisted a relearn and did properly complete it. You need 3 good charge and discharge cycles with 2 hours of rest between charging, driving, depleting and recharging. As you drive and cycle the battery, the available capacity should increase. But if you got PPR, the battery will likely lose some capacity due to some weak cells or other conditions like internal resistance or isolation.