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11-25-2017, 08:07 PM   #1
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540 II flash will fire on camera but not with Cactus V6 transceiver

I am totally stumped. I own a Pentax K-1 (fully updated), 2 X 540FGZII flashes and 3 X Cactus V6 transceivers (updated to work with 540FGZII). I have a good handle now on how the cactus transceivers work. The problem is that one of my flashes works on the cactus, but the other does not. The one that fails to fire has failed when both are meant to be firing at the same time, when it is the only flash meant to be firing and when I just press the test button on the cactus unit. It has yet to fire once on a cactus. That being said, it does fire when it is on my K1!

Any ideas? ? Is it possible to "reset" a flash?

Thanks. Any ideas are welcomed!

---------- Post added 11-25-17 at 10:19 PM ----------

New observation: When I turn on the flash that DOES work on the Cactus, it reads "P-TTL" on the screen. When I turn on the flash that DOES NOT work on the cactus, it reads "TTL". Not sure if this is significant,

11-25-2017, 09:42 PM   #2
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For sure the Pentax flash requires that you are in P-TTL mode, but there are many other function settings (master vs. slave, etc.) that you need to check are set correctly. Read your owner's manual and all the details you need to have it set for use as a slave.

I don't think it's a firmware issue and I'm not aware of any way to update the firmware with your flash unit.

Last edited by Alex645; 11-25-2017 at 09:48 PM.
11-25-2017, 10:11 PM   #3
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Make sure the flash is not set to slave mode 2

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