I have seen a lot of posts about not getting a full range charge. I am having a similar problem. I live in Massachusetts. We've had the usual cold days, but lately it's been in the 40's and 50's. Even though it has gotten warmer, I can no longer get fully charged over the 29 miles range. I did get 35 for a while until it started to get really cold in the 20's and 30's and ever since then, never got 35 again.
Sometimes I get an alert message that my charge was interrupted but then another alert right after saying my charging has completed. I did not drive my car today so I unplugged it when I got home, ran it for a bit with the heat and it dropped to 28 miles. I plugged it back in to be sure there was no interruption. It charged again and stopped at 29 on a "complete" charge. Outside temp was 50 degrees.
Other interesting thing is that my husband just purchased a Volt and picked it up on Monday. We charge on 110v outlet. He charged the last two nights and got 35 and 36 mile range on a full charge. I charged all day today at 50 and higher, and once again only got 29.
Since we have tested with the same outlet and I even tried with his new cable and he used mine, he still gets 35 and I still get 29.
I've had my Volt since December 1, 2011 (2012 model) and I have about 3k miles. I am concerned that there is something wrong with my Volt. The difference between my Volt and his Volt is that he has a lot more options like the stereo upgrade, I don't.
Does anybody have a clue why this is happening?