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Take it for a few battery exhausted to ICE turn on cycles and see if it goes up.
 

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The fuel tank holds units of fuel, not units of distance. How far you can drive on each fuel unit depends on your driving. Instead of depending on the full charge estimate, how far can you normally drive on the battery before the car switches to the internal combustion engine (ICE)? Has anything changed recently that might affect the mileage (e.g., new tires, use air conditioning more, more time driving at high speed, etc.)?
 

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Discussion Starter #5 (Edited)
I can normally drive on the battery ~34 miles unless I'm using the A/C. Nothing else has changed. I meant to say that the EV range after a full charge is now saying 27 miles only when it normally says 30+. Once I start driving the EV range would normally increase to ~ 32 and decrease from there; now, it just drops from 27 to zero. That's what I don't understand.
 

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By any chance, did you replace the tires? Did you check the tire pressures? New tires and/or low pressure can significantly affect the range and gas mileage.
 

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You're doing something different (or the car is).

- stuck/dragging brake caliper (just dealt with this on my sister's Volt)
- using more AC
- driving faster
- low air pressure in tires
 

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I can normally drive on the battery ~34 miles unless I'm using the A/C. Nothing else has changed. I meant to say that the EV range after a full charge is now saying 27 miles only when it normally says 30+. Once I start driving the EV range would normally increase to ~ 32 and decrease from there; now, it just drops from 27 to zero. That's what I don't understand.
The full charge range estimate is based on driving data collected by the computer, weighted for the most recent driving. The computer calculates an "historical use" ev mileage number from this data, then multiplies that by the amount of usable power in a full charge to create the start of day estimate.

Once you unplug and drive off, the computer makes "on the fly" estimates of the battery state of charge and current mileage to produce ev range estimates as you drive.

If "normal" driving is ~34 miles on a charge when not using a/c and ~28 when using the a/c, then the full charge estimate could be less following a few days of driving with the a/c running than after a few days of driving without a/c.

If your range estimate normally increased from 30 to 32 shortly after you started driving away from home, you likely were driving to a lower elevation (i.e., slightly downhill). Driving downhill gives you better ev mileage than the calculated mileage used for the full charge estimate, so it’s possible that multiplying the remaining usable power by the increase in mileage will produce an increase in driving range.

For example, My grocery store is 3.8 miles from my home at a lower elevation, and often my estimated ev range increases by 1 mile by the time I get there... the energy usage screen, however, shows me I’ve used 0.6 kWh to get there. The range increase is derived from the "downhill driving" mileage improvement. The range estimate return to normal as I drive further on level terrain.

If your range increase doesn’t happen anymore, then either you’ve changed the normal route so it isn’t so "downhilly," or the amount of power consumed during that portion of the drive is greater than it was before, so the increase in mileage from driving downhill no longer offsets the power used to drive that far.

In that case, what now consumes more power during that portion of the drive than it did before? Does the range estimate increase from 30 to 32 if you don’t use a/c and does not if you do? Have the traffic conditions during that portion of the drive changed (e.g., new road construction)? Tire pressure still where it was?

Some drivers have lost range when brake problems developed. Do you brakes remain fairly cool as you drive and you mostly use regenerative braking to slow down?
 

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Sorry, don't quite understand your response. The last 2 times, the battery was fully exhausted. What is ICE?
Internal Combustion Engine. ICE for short.

The range is only an estimate based on driving history. How much range does it actually get? How many KWh has it consumed when the charge is used up?
 

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Discussion Starter #11 (Edited)
Wow, that's a totally complicated mess lol! :p I had no idea that it makes these estimates based on the prior day or days range estimates. It would seem that we're being cheated every now and out of a few miles on pure electric if that's the case! I believe it must be due to the increased AC use or maybe leaving the car in idle when parked with the AC on. The ranges were very stable before the hot summer months (no AC). Other than than that, nothing else has changed. I mostly use the regen brakes as much as possible.
 

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Discussion Starter #12
I was consistently getting ~34 miles on pure electric up until the last few days or so. Why it took that long for the AC to lower my range average is a mystery, if, in fact, it's due to that. Where do I find how many KWh it uses up?
 

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It would seem that we're being cheated every now and out of a few miles on pure electric if that's the case!
It's an estimate based on history. How are we being cheated? If your driving is more efficient than what the estimate is based on, you'll get more EV miles. If it's the day you decide to have a lead foot you'll get less.
 

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I believe it must be due to the increased AC use or maybe leaving the car in idle when parked with the AC on. The ranges were very stable before the hot summer months (no AC). Other than than that, nothing else has changed.
See? Easy to figure out.
 

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Wow, that's a totally complicated mess lol! :p I had no idea that it makes these estimates based on the prior day or days range estimates.
Estimates are just that - estimates. If you fully charge your car, then head out on the freeway and test out how it feels to drive 100 mph, you’re not going to get very far on that full charge... or if you instead head out in the cool of the morning and dawdle along at 35 mph on back roads through the countryside, you’ll probably go much farther than the estimate was estimating... And think of what the Volt’s computer must be going through trying to calculate a full charge range estimate for a vehicle regularly driven by two or more drivers, each with their own set of driving habits...
 

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You're really not being cheated. It's just that the computers are taking into account your total energy usage and displaying a reasonably accurate estimate of how far you can go based on your usage. It's like saying that you fill up your gas tank and sit and idle all day long running the A/C and then complaining that you can't get the 30mpg your window sticker says you can get. It's all based on your usage. As operating conditions change, so does your mpg, or in this case your AER (All Electric Range). If the car is requiring more electricity to operate your heater or A/C, it leaves less available for travel which means you can't go as far and the system readjusts your range to better reflect what you CAN do rather than displaying what you CAN'T do.

You should fully charge your battery and look at the total kW used in the energy usage screen. This takes into account all energy including that used for propulsion as well as climate control. It should read in the 10-11kw range. If it's less, that could indicate a charging or battery problem. Do it multiple times to confirm.
 

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Discussion Starter #17 (Edited)
IMG_6921.jpg
As pictured above, this is today's usage - only got a little over 17 miles on a full charge which is the lowest I've ever gotten on a single overnight charge. The EV Range before I started driving read 26 miles; it keeps dropping a couple miles each day now. As you can see, it reads 0.5kW. I will check the kW and post when it's fully charged. The dealer said if there's no error messages, there's nothing they can do. With the battery only giving me ~ 50% of its usual EV range, something still doesn't smell right; it can't be that much of a computer usage adjustment, can it? I haven't driven it differently or done any modifications to the car since I bought it.
 

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The missing information is how much power you used to drive those 17.4 ev miles... the energy usage display on the center console should have that information. My understanding is the ELR has a 16.5 kWh battery, with ~12.5 kWh of usable power from a full charge.
 

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The missing information is how much power you used to drive those 17.4 ev miles... the energy usage display on the center console should have that information. My understanding is the ELR has a 16.5 kWh battery, with ~12.5 kWh of usable power from a full charge.
Yeah but unless the OP is driving 90mph up a mountain, I can't see how he would only be getting half his expected range. I can attest to the fact that the recent high temps coupled with more AC use has impacted my EV range on the GOM slightly (and by that I mean dropping it from 60 miles to about 57).

When you are driving, on average what is the kW usage? I know you said at rest it's 0.5 but what about when you are moving? This is an indication of how much power the car needs to move. If it's a lot higher than normal (assuming you are not driving it like a race car), it's an indication that you may have a sticking caliper as the car needs to expend more energy to get to and maintain speed.

Typically going from a stop, I use about 60kW to get up to speed (short burst) and then once at cruising speeds (on level ground), it's about 13-18kW when not coasting.
 
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