Pocket Wizard won't fire my flash with my camera in M mode...HELP !

So like an idiot I went to do a shoot indoors with my 1dMkIII for the first time and for some reason I can't fire my 580EXii remotely with my Pocket Wizards and my camera set to "M" mode. It fires with the camera in AV mode. The sun kept going in and out through a window and it kept changing my lighting all the time.

I NEVER had this problem with my 50D.

Could there be something set on the camera that is preventing firing in M mode ?

Yes I know, I should have tried this BEFORE I went to shoot

Can anyone help ?

Which Pocket Wizards?
ETTL or manual on the flashes?

Heath wrote in post #14412778
Which Pocket Wizards?
ETTL or manual on the flashes?

MiniTT1, FlexTT5.

Manual on the flash also

alexxn wrote in post #14412795
Manual on the flash also

There goes my theory.

For ETTL, my understanding is that in AV mode, the camera uses the flash for fill, but in any other mode, the flash is considered the main light. I was thinking maybe the camera thought there was enough light and would not fire the flash.

It's very likely I just made all of this up.

Looks like it was a good as dead battery - I guess they don't last that long and $7.25 a piece....I just picked up 2 so I have a spare...