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I recently had a wiring issue at my house so I couldn't charge my Volt for approx a month. I have multiple vehicles so I only put about 800 miles on it during that time on the ICE.

This past weekend I fixed my house and gave the volt a full charge... I get in the car Monday morning and the expected range is showing 30 instead of the usual 38. Figured it was because it was the first charge and drove on... I was getting better than expected range (i.e. I was 9 miles into my trip to work and it still showed 27 miles remaining so I was doing better than the computer expected). I drove to dinner, then home, plugged in and forgot about it. Then this morning I get back in and it's fully charged showing the same 30 mile range. I did better than expected again just like yesterday.

So... is this something I can reset? Any thoughts in general? I could see if it was showing a 10 percent loss but it's showing well over 20 percent down on battery.

My car IS part of the recall (just found out). If the battery is hosed at what threshold will GM replace it under warranty?
 

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I believe that your "expected range" (also known as Guess-O-Meter) will eventually work itself back to normal. Obviously if you are getting better than "expected range" it is not a battery degradation issue. What was the normal expected range before the house issue? I would bet that it will return to that number after a week or two of normal driving conditions. And no, it is not something you can reset, it will work its way back up. Let us know.
 

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Keep in mind that the range projection is based on ALL driving history. So if you were driving on the ICE like it was a race car then the range projection will reflect that as well.

VIN # B0985
 

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I've had my 2013 for just over a month. It started at 47Km. and after several less than half battery trips it eased up to about 53 Km then 57Km. where it stayed. I did my first full battery to depletion last week and got 65Km. Next charge it showed 65 Km. Do one or two full to empty runs and it will correct itself pretty quick. On partial runs it takes longer.
 

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On my 2013 I am getting more range on the guess o meter and actual range than ever before. I get an average range of around 88-90 Km. I drive very carefully and do not use the HVAC system at all. Recently, the guess o meter was showing 98 Km but I have not achieved that actual range as I have shorter trips and charge often. The range really drops when my son and wife drive as they accelerate hard and use heating/cooling. I think it's awesome and just love squeezing out more range, especially when the advertised range is in the low 60's. I'm hoping it get's to 100 one day.
 

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I know it is odd but

the range will go up more based on your number of posts :)

we have the data to prove it :)))
 

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Bought a 2012 about 6 weeks ago. It probably hadn't been driven much since winter so originally the estimated range wasn't even 30 miles at full charge. Within a week or so it was up around 40.

I also believe that the previous owner rarely charged the Volt by the time they traded it in based on the lifetime mpg. At first I wanted to reset it, - I don't want to be judged on someone else's poor charging habits. :) But I think there's value in having that information, plus I get a small amount of satisfaction from watching it tick upward.

You should be seeing normal range estimates before long.
 

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I recently had a wiring issue at my house so I couldn't charge my Volt for approx a month. I have multiple vehicles so I only put about 800 miles on it during that time on the ICE.

This past weekend I fixed my house and gave the volt a full charge... I get in the car Monday morning and the expected range is showing 30 instead of the usual 38. Figured it was because it was the first charge and drove on... I was getting better than expected range (i.e. I was 9 miles into my trip to work and it still showed 27 miles remaining so I was doing better than the computer expected). I drove to dinner, then home, plugged in and forgot about it. Then this morning I get back in and it's fully charged showing the same 30 mile range. I did better than expected again just like yesterday.

So... is this something I can reset? Any thoughts in general?
A fuel tank holds units of fuel, not units of driving distance. A range estimate is obtained by multiplying the available units of fuel by a mileage estimate (how far you drive per fuel unit).

The full charge, start of day range estimate uses data gathered during your previous drives, weighted for the more recent data, to create a mileage estimate to use for the range calculation. The computer is not really disappointed with you if you don’t get that range, or happy for you if you do "better than expected."

The start of day range estimates are fuel-specific. EV range estimates are based on recent ev driving. If you have a 20 mile commute you drive at 40 mph or less, your full charge range estimate is going to be good because the computer thinks you drive at or below 40 mph all the time. If you habitually drive beyond battery range, but switch to Hold Mode whenever you drive faster than 40 mph, you’ll have a similar good full charge ev range estimate because the ev range estimate is based on the slower-speed ev driving. The other driving you did using Hold Mode and gas will influence your gas range estimate. It’s not how far you drove recently, it’s how efficiently you drove using the given fuel.

You, however, haven’t been able to charge for a month, driving on gas. The algorithm that calculates the ev mileage used to calculate the full charge range is using data from a month ago, but little or no "more recent data." Lack of current data might be the reason for the more conservative range estimate. Creating current data by driving in Electric Mode will help produce an ev range estimate that more accurately reflects your driving habits.
 

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A fuel tank holds units of fuel, not units of driving distance. A range estimate is obtained by multiplying the available units of fuel by a mileage estimate (how far you drive per fuel unit).

The full charge, start of day range estimate uses data gathered during your previous drives, weighted for the more recent data, to create a mileage estimate to use for the range calculation. The computer is not really disappointed with you if you don’t get that range, or happy for you if you do "better than expected."

The start of day range estimates are fuel-specific. EV range estimates are based on recent ev driving. If you have a 20 mile commute you drive at 40 mph or less, your full charge range estimate is going to be good because the computer thinks you drive at or below 40 mph all the time. If you habitually drive beyond battery range, but switch to Hold Mode whenever you drive faster than 40 mph, you’ll have a similar good full charge ev range estimate because the ev range estimate is based on the slower-speed ev driving. The other driving you did using Hold Mode and gas will influence your gas range estimate. It’s not how far you drove recently, it’s how efficiently you drove using the given fuel.

You, however, haven’t been able to charge for a month, driving on gas. The algorithm that calculates the ev mileage used to calculate the full charge range is using data from a month ago, but little or no "more recent data." Lack of current data might be the reason for the more conservative range estimate. Creating current data by driving in Electric Mode will help produce an ev range estimate that more accurately reflects your driving habits.
I think you are wrong. When you are driving on the ICE you are really driving on electric miles produced from burning gas in the ICE. The ICE creates electricity which temporarily passes through the battery system. So the algorithm looks at energy use per mile regardless of the source. The EV range is based on ALL driving not just pure battery electric energy use.

VIN # B0985
 

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I think you are wrong. When you are driving on the ICE you are really driving on electric miles produced from burning gas in the ICE. The ICE creates electricity which temporarily passes through the battery system. So the algorithm looks at energy use per mile regardless of the source. The EV range is based on ALL driving not just pure battery electric energy use.

VIN # B0985
I could be wrong in my analysis, indeed, and my 2012 Volt has no Hold Mode, so I can’t test it out by starting out with a full charge, drive carefully for a few low speed miles on grid battery power (for the good ev mileage), then switch to Hold and drive 30+ miles of high speed driving on the freeway using the ICE, and then fully recharge to see if my full charge ev range estimate drops because of the high speed, "low electric mileage," driving.

I have, on the other hand, driven from Oregon to Michigan with no recharging stops, using the range extender, and after recharging at my destination, obtained a full charge ev range estimate consistent with my around-home, slower speed driving habits, clearly not modified by days of freeway speed travel.

In Extended Range Mode, the engine’s function is to use MGA to generate electricity, but the Gen 1's "seamless transition to gas," is, in effect, a seamless transition from grid electricity to gas-generated electricity. The generator output does not necessarily pass through the battery at all (that would be less efficient). Wikipedia says that when the battery is depleted, "the electrical power from the generator is sent primarily to the electric motor, with the excess going to the batteries, depending on the state of charge (SOC) of the battery pack and the power demanded at the wheels." Reviews of the Gen 2 Volt say "MGA’s electric output is sent down to MGB to power the wheels," indicating a similar process in the Gen 2 Volts, generator output powering the motor, not merely recharging the battery.

Electric Miles are miles driven using the grid power stored in the battery. A good portion of Gen 1 Gas Miles may, indeed, be miles driven using only the electric motor running on gas-generated electricity (in single motor configuration), but I suspect it’s not easy to estimate kWh Used for Gas Miles when the battery state of charge remains relatively steady. If the estimated EV range is an estimate of how far I can drive on the grid electricity in the battery, it should be derived from my grid electric use only.
 

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I know it is odd but

the range will go up more based on your number of posts :)
Absolutely. I'm getting 600 miles on my 2011 Volt, haha
 

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I'll let it ride for a few days and see how it goes. I didn't drive it today so I won't know more until tomorrow anyway.
 

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I could be wrong in my analysis, indeed, and my 2012 Volt has no Hold Mode, so I can’t test it out by starting out with a full charge, drive carefully for a few low speed miles on grid battery power (for the good ev mileage), then switch to Hold and drive 30+ miles of high speed driving on the freeway using the ICE, and then fully recharge to see if my full charge ev range estimate drops because of the high speed, "low electric mileage," driving.

I have, on the other hand, driven from Oregon to Michigan with no recharging stops, using the range extender, and after recharging at my destination, obtained a full charge ev range estimate consistent with my around-home, slower speed driving habits, clearly not modified by days of freeway speed travel.
2012 seems to maintain two histories for estimating range: A charge-depleting one for pure EV and a charge-sustaining one for MM and normal "out of battery" operations. They don't influence each other much if at all -- I can swing the EV one up or down up to 8 miles per charge by varying my driving, but the estimate on a full tank of gas won't change more than maybe five miles total until I actually use some. During ERDTT season, it'll be about 300 miles per tank, and when the weather warms back up and I take the first 150+ mile trip of the spring, it's back up to just under 400 miles for a full tank, where it stays all summer.
 

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I recently had a wiring issue at my house so I couldn't charge my Volt for approx a month. I have multiple vehicles so I only put about 800 miles on it during that time on the ICE.

This past weekend I fixed my house and gave the volt a full charge... I get in the car Monday morning and the expected range is showing 30 instead of the usual 38. Figured it was because it was the first charge and drove on... I was getting better than expected range (i.e. I was 9 miles into my trip to work and it still showed 27 miles remaining so I was doing better than the computer expected). I drove to dinner, then home, plugged in and forgot about it. Then this morning I get back in and it's fully charged showing the same 30 mile range. I did better than expected again just like yesterday.

So... is this something I can reset? Any thoughts in general? I could see if it was showing a 10 percent loss but it's showing well over 20 percent down on battery.

My car IS part of the recall (just found out). If the battery is hosed at what threshold will GM replace it under warranty?
don't panic, yet, remember that there are 2 range estimation modes, the one in effect when you turn on the car, which seems to me to average the last 2 weeks or so, and the "in-trip" mode, which seems to me to be calculated from the last 3-5 miles and is time weighted to favor the last few minutes. climb a long hill and the estimated remaining range will plummet, drive down a long gentile slope and it goes up...
 
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