5d shutter problems!

I have had my 5d for 2 years now with no problems. Recently I have had a problem develop with the shutter. The first time it happened was when it was really cold and the battery ran down quickly. The shutter did not fire properly and only a slim line of the image taken was showing up on the lcd. Then this weekend it did it again when the battery got low and would not quit when I put in a fresh battery. Is this a battery issue, maybe not charging fully now that they are 2 years old, or is there a reset that will be needed possibly at Canon?

If it were just a battery issue I would think it would self resolve with a fresh battery.. Since it did not it sounds like a shutter problem. How many actuation's? I would send it to Canon for help.

It has less than 20,000 actuations. Thanks Ed.
Both batteries are the same age, and I had the problem with both batteries when it was cold.

I would say get another battery and test it out before sending it to Canon. You're probably going to need a new battery eventually so why not get it now and be done with it? I would suggest Opteka batteries. My 50d runs better with them than the original canon battery. It is also SIGNIFICANTLY less expensive. I hope this helps.

Thanks for the help, Erik.