[bdery]

I had posted a thread some time ago, after getting a used Pentax AF540 FGZ flash. I thought there was a problem with the zoom head, then thought it was user error. Now I know it's not, and I have narrowed the problem.

When the sync is set at first curtain before turning on the flash, the zoom sets itself to manual, 16mm and it will not zoom whatever I do. Zooming an attached lens, pressing the zoom button will not zoom the head. The focal length display will update but the head won't zoom. Opening the wide diffuser updates the display to 13mm but again no zoom.

Setting the sync to any other mode (like second curtain or HSS) before turning on the flash seems to be the solution. When I do that, everything operates as expected, in manual zoom or auto. I can then switch back to first curtain if I want without problems. Turning the flash on or off repeats the same observations.

Everything else about the flash works as expected.

I have read on the web about broken tabs/levers on the wide diffuserr but this is not the problem. I have also read about the zoom motor getting stuck but it does not seem to be the problem either.

I can use the flash as is, but I worry that it might suggest a deeper problem.

Any opinions?

[SOldBear]

Very interesting. I have no clue as how to attack the problem.

If the flash is out of warranty, I'd use it as is. The symptom is annoying but bearable. I don't think it will get worse (but I've been proven wrong many times).

[bdery]

Yep, the flash is out of warranty. The seller and me are in contact about this. I also wrote to Pentax, the answer so far is that there's no easy troubleshooting left to be done and I should send it for repairs. I might use it as is indeed but it's annoying to say the least.

[bdery]

A little more info on this. Pentax USA said I should contact Pentax Canada or send them the flash. Pentax Canada never replied. (kudos)

However, after using the flash a few times on second curtain, it appears that for now at least I can go back to using first curtain... Maybe a contact was poorly made, but now after moving the sync button a lot it seems the flash operates as normal... Strange to say the least.