Question...

I have a Canon 6d & a Canon T31 .. I also have a NeewerTT560 Speedlite 2 Yongnuo RF-630 C ... I am having trouble making the flash work with the triggers.. I had it once.. on the T3i.. But now I cant get it to work properly on either one.. If you had any suggestions? Everything has new batteries.. Ive even changed the settings in the cameras.. But still nothing..

It won't fire at all? Are the tranceivers on the same channel?

603's channel set is tiny and behind the batteries on the inside.. not much chance of bumping them unlike the 622's..

So then we look at do they talk? if you half press(the shutter), do both lights light up green on the speed light 603 trigger?

If that is yes, then we look at did it seat the foot far enough into the 603 hot shoe?

If yes then is it on the correct way? (yep, I've put one on backwards on a flash.. (face : palm))

If none of this helps.. please post a picture showing the camera and the flash with triggers.. and settings on the camera.

you probably already did these, but I'll state the obvious:

make sure you have fresh batteries in the 603's. This has caught me more than once when the lights worked but wouldn't fire the flash somehow.

I'm not familiar with the speedlite, but just make sure it is on manual model.

I noticed my 603's do this for about the first minute or so after I turn them on. Like if they're searching for a connection. After that initial minute or so I can only assume they've "found each other" because they work like a charm.