Paul C. Buff, Inc. Technical Forum

i only used this once. now when i connect it to my 5DII hot shoe, it doesn't show anything that it's on. i pressed the test button and it didn't test fire. there are no indication of any sort of red light coming from the CST unit. i thought it was the battery but that ended up nothing. could there be a defect because i tried on both my bodies. 40D was the original that i used it on, and my 5DII.

-chris

first try flipping the battery over. Often when a new battery is used, it is installed upside down. When the battery is installed properly, the LED will blink 3 times when the battery drawer is shut, then once for each activation (either by the test button, or by camera contact). If it blinks 3 times when activated, then the battery is getting low.

err thanks. it works, i felt stupid. i thought i had it the right way. thanks again.