Fuji GA645 built-in flash problem

Discussion in 'Medium Format Cameras and Accessories' started by drumlin, May 18, 2011.

  1. drumlin

    drumlin Member

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    I never use the built-in flash on my GA645, but not long ago, I thought it might work okay in a pinch down a dark hallway (it didn't). Still, it seems that pressing that flash button to pop it up has had some nasty side effects. Now, even when the flash is down, it still charges up and fires in all modes and situations. I don't know where the sensor is that tells the camera that it's not in the ready position, but it seems to be malfunctioning.

    I'm thinking of tearing in and snipping some wires, since I don't want flash exposure most of the time, and when I do, I'll bring in the external units. Plus, I'm not thrilled at what this is going to do to my battery life. Anyone else had this issue, and if so, is there something I'm missing so that I don't feel the need to perform surgery on my camera? Thanks in advance!
     
  2. John Koehrer

    John Koehrer Subscriber

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    There's likely to be a simple switch somewhere around the pivot for the flash. sometimes a small hole or protruding pin will be the switch.
     
  3. drumlin

    drumlin Member

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    I thought the same, but I've poked and prodded for something obvious and I haven't found anything. Any switch is probably somewhere inside.

    Just sending out a feeler to see if anyone else has come across this problem before. I've searched the internets for answers and come up short (not that this is a common camera with lots of web presence...)
     
  4. drumlin

    drumlin Member

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    Just to update, I couldn't figure out anything easy or obvious, so surgery was prescribed. I simply took the builtin flash out (4 skrews), snipping the wires along the way. The bulb capacitor still had a little juice in it, so it made a happy popping noise that scared the poop out of me (FYI kids don't try this at home or at least make sure you've got insulated snips, which I luckily did...).

    The flash unit needs to be there for the little clip to catch and keep it in the inactivated position, so black tape is there to keep it down and give me a little more street cred. Probably killed any chances of resale, but it's such a fantastic camera I'll probably run into the ground anyway..
     
  5. John Koehrer

    John Koehrer Subscriber

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    Be surprised how fast your arm can move when you discharge that cap with a screwdriver.
    Damn near put my eye out.
     
  6. Dan Daniel

    Dan Daniel Subscriber

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    Just picked up a GA645 with this problem today. No matter the position of the flash, it would fire if the meter decided it needed it. It had obviously been doing this for a while, looking at the slightly melted plastic from the hot flash tube in the flash cavity.

    With the flash open, there is a plastic piece at the front of the cavity, held in by one screw at the front edge of the upper lip. Remove this screw and fiddle the large plastic piece and it will come out.

    There are four wires traveling from a circuit board up front into the flash head. As these four wires go along the upper shelf and head into the arm holding the flash, one wire had an extra 'loop' in it. Best as I could find, there is a relay switch on this side under the wires. Well, 'under' in my case, since this was the problem. The longish wire had folded itself into the slot. I rearranged all of the wires, getting them clear of the edge (this is the edge closest to the shutter button side of the camera).

    If you look at this edge from both above and below, you'll notice a thin whitish tab of plastic connected to a smallish 'blob' which I think is a relay. I actually didn't ever truly decipher the mechanism, what tab on the arm is hitting the tab on the relay. I do know that now the flash works fine. Off when down, on when up. All is right with the world....

    Yeah, those flash caps are a kick. Taking apart a Polaroid Spectra to get the mirror out, I didn't think about the old film pack keeping the flash charged. Cutting the flash wire put a solid 1/32 inch hole in the metal edge of the stainless steel snips I was using.
     
  7. Steve Smith

    Steve Smith Member

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    Cutting just one wire won't do that. Cutting the right (or wrong) two at the same time will!


    Steve.
     
  8. Dan Daniel

    Dan Daniel Subscriber

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    Maybe I was cutting 2 at the same time. My memory of the event is a bit muddled.... : )
     
  9. drumlin

    drumlin Member

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    Dan, nice work. Seems like you actually fixed the problem rather than whole hog disabling the flash altogether. I'm a bit of a bull in a chinashop sometimes. I do kind of like the electrical tape holding my flash down. That, along with the word "Professional" stamped on the side of the camera lets people know that I mean bizness. :smile:

    Oh, and the tips of my snips are pitted and discolored as well. Them little capacitors pack a punch...
     
  10. Dan Daniel

    Dan Daniel Subscriber

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    drumlin, a little work would probably get your flash back fine. If you take out the cover plate on the flash well interior, you'll see four wires coming off of a circuit board toward the front. These go to a ledge and back to the pivot/base of the flash. It's one of these wires that got caught up in the slot on the shutter button side of the well.

    Looks like it wouldn't be hard to replace all four of those wires and resolder them to the circuit board. Ah, the days before surface mount technology and multi-layered boards..... Or splice on the front edge- lots of spare room in that area.
     
  11. BAB

    BAB Member

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    Don't forget to insulate the splices :smile: !
     
  12. 12th St David

    12th St David Member

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    Sorry to revive this thread after so long, but I just got a GA645 with the same problem. I found this YouTube video that purports to address it, though it's done in a sort of wordless Marcel Marceau-camera-repair style (with amusing characters drawn on the repairman's gloves), and I'm a bit confused as to what he actually did.

    http://www.youtube.com/watch?v=4EXjkDjnzoU

    One helpful diagnostic I noticed was that the flash signal is on in the LCD in M and A mode, even when the flash is not popped up.

    But I noticed that he took off the whole top of the camera, while, if I read your post correctly, you only took off the flash assembly itself.

    I know it's been a while since you posted this, and it might not be fresh in your memory, but any tips for a repair newbie on trying to accomplish this myself?

    Thanks!
    David
     
  13. mr rusty

    mr rusty Member

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    Somewhat of an understatement maybe? You only do this once and surely it is a right of passage to anyone who tinkers with cameras. When I was trying to repair an old flash I knew enough that the capacitor needed discharging, but evidently not enough to do it safely. The bang when I stuck my screwdriver across the contacts was a little more that a happy popping noise. More like an ear cracking explosion that scared the s**t out of me.
     
  14. RattyMouse

    RattyMouse Subscriber

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    My GA645 was worked on long ago when I found that the rotary dial was acting all strange. The tech took apart the top of the camera and cleaned the dust out of that area. I was sitting there while the work was being done when out of nowhere, the MOST HELLACIOUS BOOM you could imagine sounded. BANG!! I thought for sure my camera was reduced to a worthless piece of junk. The tech seemed totally nonplussed, and I had to be firmly convinced that he didnt ruin it. But he didnt and I have operated the camera just fine for several years. He cleaned the dial nicely and it has performed flawlessly.