My 2010 GC's smart key started working only intermittently to unlock the doors and trunk a week ago, but appears to consistently start the car. I thought maybe the internal battery needed replacing but asked the store clerk to test it before selling me a new one. Well, it moved the needle to the limit of the green indicating a strong charge. Clerk suggested I clean the battery thoroughly with a soft cloth and blow out any dust w/in the interior of the key. I did that and even went around the interior of the key with a lightly moistened Q-tip. Still works intermittently on the doors and trunk, but started the car immediately. I can always use the spare regular key holstered in the smart key to open the doors, but would rather it worked as before this intermittent problem came up. The other smart key in my wife's possession works fine. Anyone have any ideas what's wrong with the one I use?