Just to be sure... your batteries are all ok? Maybe try some new AA's in the grip in case it's a problem with the Canon battery?
I took the grip off and used the Canon battery in the slot as per standard. Also tried an unbranded battery. Still no joy. Have not tried the AA route, I will do, but cant see that helping.
As stated try a set off AA's in the grip and do a full reset on the camera, see if that helps
That sounds like your charger has cooked the batteries as they dont work in grip or body.
Cheers for the reply. I can see what your saying, but they worked fine all weekend, and now done work, havent had a charge between. I follow your logic, maybe a drain and recharge might solve it?