30D won't focus w/o battery grip
Took out my 30D yesterday to shoot pics of my kid and low and behold it would not focus. Focus motor just goes and goes but never locks in. Full manual works fine. I thought it might have something to do with my shutter button because I've been having some issues with it (like MANY others have reported) where the shutter button has become less and less responsive over time. So I attached my battery grip to see if the auto focus would work on the battery grip shutter button. Worked like a champ so with the battery grip still attached, I try the normal shutter button and it WORKS!! Take the battery grip off and go back to normal battery and it will not focus again.
Is it possible that I need to replace the battery? (it is fully charged)
Anyone have any other ideas what this could be?