580exII Won't Fire AF Beam in Manual Mode.

[TurboDSM91]

As the title states, I'm shooting with a 7D. The AF Beam fires in full auto mode but nothing else. I would rather not shoot in full auto but, I was in a squeeze and had to do it. I set the C.Fn setting correctly to get the AF Beam to fire but it doesn't.

 

[Overread]

Change your focusing mode

The AF assist beam only fires when your focusing mode is set to single shot, if you have it set to either of the continuous modes the AF assist beam won't fire.