I got this model unfortunately it does not flash. It powers up if I hook it up to my Godox pb960. All the buttons seem to work except the test flash button, or when I PC sync it with my camera. It even reports under exposure (of course) if I use auto as the flash never goes off. Do you know if it's an "easy" fix like opening it up? I am not handy at all. The bulb works even the casing felll off as I put it into my sunpak 120J and it works ... Does anyone know how to open this thing? Or any diagram online? Thanks.