I understand that range is expected to be less during the winter, but the way my range reduced has me wondering.

Here's the story:

I got my 2012 Volt in September, and drove it excusively in town without using the IC engine for the first two months. I was getting 41-42 miles of range, in temperatures that went from 80's down to high 50's.

Then I had to go on a road trip to Florida and back, so I started using some gas.

On the trip home, the check engine light came on. (side note: at first, I just thought this meant "gas engine operating", the symbol could be clearer). So when I got back to town, I scheduled an appointment with the dealer.

On the morning of the appointment, of course, the check engine light was no longer on. The technician ran all the codes and they were all "communications failure" codes. Neither he nor the people at Chevy he consulted could find any problems with the car other than this transient issue. The car was plugged in at hotels each night, maybe it was caused by a power glitch, who knows?

Car gets returned to me, and all is fine -- except my range is 34 or 35 miles. And nothing I do gets the range to budge. It was 35 miles in late November (temps in the 50s), it's 35 miles now (temps in the 30s and 40s). The car gets 3.4 or 23.5 m/kwH no matter what.

Now, if the range had gradually reduced as we went into winter, that would be one thing. But it was 40+ miles before the light came on, and 35 miles right after the dealer visit, and the weather was about the same.

Can anyone shed some light on this?

My understanding is EV range is estimated based on recent driving. The long road trip would lower the EV range calculations as you mostly drove highway and infrequent charges. Before you were in a repeating pattern with actual EV range. I'm sure others will fill in things I've missed.

Your Check Engine could have been caused by interrupted charge cycles on the motel plugins on the trip

I understand that range is expected to be less during the winter, but the way my range reduced has me wondering.

Here's the story:

I got my 2012 Volt in September, and drove it excusively in town without using the IC engine for the first two months. I was getting 41-42 miles of range, in temperatures that went from 80's down to high 50's.

Then I had to go on a road trip to Florida and back, so I started using some gas.

On the trip home, the check engine light came on. (side note: at first, I just thought this meant "gas engine operating", the symbol could be clearer). So when I got back to town, I scheduled an appointment with the dealer.

On the morning of the appointment, of course, the check engine light was no longer on. The technician ran all the codes and they were all "communications failure" codes. Neither he nor the people at Chevy he consulted could find any problems with the car other than this transient issue. The car was plugged in at hotels each night, maybe it was caused by a power glitch, who knows?

Car gets returned to me, and all is fine -- except my range is 34 or 35 miles. And nothing I do gets the range to budge. It was 35 miles in late November (temps in the 50s), it's 35 miles now (temps in the 30s and 40s). The car gets 3.4 or 23.5 m/kwH no matter what.

Now, if the range had gradually reduced as we went into winter, that would be one thing. But it was 40+ miles before the light came on, and 35 miles right after the dealer visit, and the weather was about the same.

Can anyone shed some light on this?

35 miles with temps near freezing is normal

The CEL comes on when you use the delayed charging and do the "plug-unplug-plug" too quickly for an immediate charge. Do you have the delayed charging turned on?



On the trip home, the check engine light came on. (side note: at first, I just thought this meant "gas engine operating", the symbol could be clearer). So when I got back to town, I scheduled an appointment with the dealer.

On the morning of the appointment, of course, the check engine light was no longer on. The technician ran all the codes and they were all "communications failure" codes. Neither he nor the people at Chevy he consulted could find any problems with the car other than this transient issue. The car was plugged in at hotels each night, maybe it was caused by a power glitch, who knows?

Car gets returned to me, and all is fine -- except my range is 34 or 35 miles. And nothing I do gets the range to budge. It was 35 miles in late November (temps in the 50s), it's 35 miles now (temps in the 30s and 40s). The car gets 3.4 or 23.5 m/kwH no matter what.

Now, if the range had gradually reduced as we went into winter, that would be one thing. But it was 40+ miles before the light came on, and 35 miles right after the dealer visit, and the weather was about the same.

Can anyone shed some light on this?

Can anyone shed some light on this?It's probably just the estimate not the actual range. After a trip to the mountains which involved driving in EV mode back down the mountain the range estimate was 58 miles (someone told me the range estimate doesn't go this high but that's what I remember). The actual range didn't really change, it was just the prior driving boosting the estimate. You may have done the same thing with highway driving in CS Mode.

Funky chargers have been known to set off the CEL but usually closer to the time the charger was in use. But I wouldn't worry too much about it. The CEL seems overly temperamental.

For anyone who uses level 1 charging and are afraid of a range reduction, they should really use one of these:
http://www.amazon.com/P3-International-P4400-Electricity-Monitor/dp/B00009MDBU

That way you can easily calculate your energy consumption in watts/mile. A good range would be between 280-350 watts/mile.

A optimal value would be around 295 watts/miles.

Calculated as 10.4 kWH DC divided by 0.88 (88% AC to DC Charging efficiency) divided by 40 miles EV range.
So (10.4/0.88)/40 = 295.

If you EV range drops significantly but your energy used to charged remains the same, that basically means you're just using more energy per mile, but your battery capacity remains the same.

I don't pretend to know all the details of the 10 million lines of code in the Volt, but I can tell you one thing: If the car calculates that it's out of juice, it switches to ICE no matter what.

It sounds like somehow your car thinks it has 35 miles of range so that's what it's going to give you no matter what.

I have had my range fluctuate wildly for only brief moments at times: 21 miles one to 42 miles the next without significant changes in temp, terrain, or technique. Normally, it's in the low 30's, and those spikes up or down are anomalies that have no explanation from what we know as owners.

Lot's of people will talk on here like they know exactly how the car works, but there's no way unless you wrote all those lines of code. The car clearly works pretty well, but it has its idiosyncrasies.

An interesting experiment for you: Put on the cabin heat on full with seat heaters and defrost (open the windows to cool yourself down), turn on sport mode, and drive agressiving in acceleration and braking, and include lots of highway speeds to see how many miles you get. At some point it has to give you less than 35 miles.

P4460.01
I like this one better
P3-International-P4460-Electricity-Monitor

has a memory to hold the data when the power is off.

viewability and readability are still not up to par -

I don't pretend to know all the details of the 10 million lines of code in the Volt, but I can tell you one thing: If the car calculates that it's out of juice, it switches to ICE no matter what.

Switching over to CS mode is based on measurements of the battery state of charge. Range remaining has to be an estimate based on lots of variables, but the actual switchover is based on hard data.

The other day in NJ I started a trip on New year’s Eve and it showed an estimated a range of 35 miles. I ended up with 44.5 miles and the temp was in the 40's with an overnight stay. That range estimation is just that.

Then my wife made her normal trip to work yesterday and blew out the charge and got 25 miles on electric.. it was in the teens and the car sat outside all in the cold. I have never had that type of range before.. But still that is an estimate.

It all depends on current driving techniques and temperature for that day.. I never have the same results when I start on the estimate and what actually what ends up happening.

Switching over to CS mode is based on measurements of the battery state of charge. Range remaining has to be an estimate based on lots of variables, but the actual switchover is based on hard data.

So you're positive that it doesn't use tea leaves to determine the switchover? ;)

VBG!!!!!!!!!!!!!!!!!!!!!!!!!!!11

Thanks for the replies. I do use delayed charging and IIRC did do the plug-unplug-plug trick while on the road.

Don't quite understand why using the gas engine would potentially change the range estimate (as one posted suggested) though. These would seem to be independent variables.

I'll monitor the range estimate and if it doesn't climb in the spring, revisit the issue.

On the bright side, my free Progess Energy 240v charger got installed yesterday, so now I can do an almost complete recharge during the 3 hour off-peak afternoon window.

I live in Montreal as you can imagine it gets quite cold here, when I first got my Volt in September the car had 39 mile range I am now down to 24 miles and dropping. I have brought the car back to Chevrolet dealer and the response was GM is looking at the problem. I have since then called my ambassador and i am still waiting for response. I tried putting the car in the garage at 60 degrees and recharging several times and no difference.
Has anyone heard of a fix by Chevy?
Thanks:confused: :confused::confused:

For Chevy to fix it, there'd have to be something broken. Without knowing more about what you've been doing, we can't tell, but so far it sounds fairly normal.

I think all of the Canadian cars are 2012s? If so, look at the energy usage screen on the center console after you switch to gas. If it is showing 9.7-10.6 kWh used, then the car is working normally and your low mileage is a result of weather conditions, climate settings, and driving style. Are you using comfort? Is the temperature cold enough that you're seeing 'engine running due to temp?' How fast are you driving?

This sounds perfectly normal for the Canadian winter. I have not got more than 35km range on my Volt when temps are below 0 celcius. Some days (like when it was -21 C outside) it has been as bad as 25km.

This is completely normal behaviour and is well documented in many online articles and in the owners manual.

Comfort mode is the real kicker, and remember it takes in consideration your last drive(s) with comfort on so you may not get your numbers back up instantly if you found you were running comfort w blower.

My cold weather thinking:
G/F + Comfort = e-range in high 20's, low 30's (deal with it!)
Me alone no comfort, maybe heat on seat and short trips = high 30's
Warm weather we will be back up to 40's but that's what it is.

I am pretty impressed with the range estimates. This AM I did a 34.62 mile round trip defined by a mapquest route, the estimate at the start was 44 miles. The estimate at the end was 8 miles. Pretty damn close, I certainly can't complain.

I have found out that having my wife drive my car lowers the range, I am trying to find the page in the manual that explains why this is. :)

Seriously before you have GM look at the car consider my wife. She just drive it like a regular car if its cold she put the temp at 77 and comfort no consideration for range, she gets 25-28 when its in the 40s. Then when I drive I use 69 and eco and get 33-36 at the same temp. The heat is a real killer of range, I have also noticed that the colder it its the more hit in range you get when driving above 50 mph. The other day I pre-heated used only seat heater to work and drove a little slower maxed out at 60 instead of 70 and then set temp to 68 and ECO back from work and even if it was in the high 30s, I then got 40 mile range.

I went from 29 to 41 in a day mainly based on CLIMATE control settings.


I was getting about 30 EV miles before my update. Estimate for the next several days after were like 37, 37, 34, 32, 31, 32. I actually got 29 actual miles a day or two ago.

Today I got 41 actual miles. I was using ECO this morning but went after work to play racquetball a ways away. On the way back I was still hot so I was using very limited climate controls. Pulled in home at over 41 miles driven and 1 mile left on the battery. It was 43F.