Repair of a Sunpak PZ42X Flash aka. FujiFilm EF-42

[chefkoch84]

Hello all,

please help me with some thoughts on a repair of a
Sunpak PZ42X Flash aka. FujiFilm EF-42.

The symptoms are:
- Powers up normally
- Loads the cap. (incl. typical flash load sound)
- Screen and menue is normal
- Does not fire the flash. (manual via button)

Images:

High voltage Board

Backside:


Cap:


Flash tube


Dimensions


What I tried for debuging:

First Rule of debugging: "Measure voltages first"

--> Battery Volage ( 4*1.5 V good) 
--> High voltage after flash loaded (~330 V ) (measured on the cap) <-- should be good?

I found this curcuit...


I unpowerd the system and use one of this crappy china component testers to test:
- the huge diode on the flash board : seems good
- both sides of the inductor on the flashboard "transformer" : seem good (detects inductors)

So I thought I am a smartass and just try to mimick the swich by shorting the gray and the white cable on the connector to the high voltage board. (I used a screwdriver) ... no flash .. no discarge .. nothing happend.

So I thought I perhaps mixed up the trigger line and shorted the pink cable and the white cable. --> huge discharge explosion on the screwdriver tip... very very load ...   now I realy beleve that this thing can kill you.
I just hope that I did not destroy something here... but I guess I just discharged the cap...kind of fast.

Summing up:
----> Is the flash tube dead?
Do you have any further ideas how to test if the flash tube is kaktus?

There are very little replacement tubes around. Do you have an idea how to find the correct one?
Shouldn't be there some kind of power rating?  Aparently ther is no official replacement part available.

Could this be usefull?
eBay auction: #http://www.ebay.de/itm/Xenon-Flash-Tube-lamp-repair-Flashtube-4x40mm-Photo-strobe-eclat-Blitzrohre-/111510728317?hash=item19f68eae7d

Any further usefull steps for debugging?
I sadly did not find a service manual.  All those testpoints looked somehow very promising.

Thanks so much.
Greetings
Max


edit: image of cap was missing

[singapol]

Hi, Very sorry to hear of your flash's demise. On hindsight perhaps before the explosion the fault could be a simple one.Either there is a break in the wire harness or a faulty momentary manual switch which
I hear is fairly typical.In cases like this I think it's not worth the time because there may be collateral
damage especially to the contriller chip so it's best to write it off.However you can keep the flash for parts to do projects when you need something of a photographic nature. A new flash is rather cheap and you can get back to photography again.

Edit: If the lcd does not come on or it displays rubbish then the controller chip may have sustain damage.

[chefkoch84]

currently I do not have any hints that the explosion destroyed something. Operation and symptoms are still the same.
Controller chip is for sure still working.
Btw. I did those picures after the "explosion".

[ElektroQuark]

You say you can't fire it in manual (pushing the test button), a camera can fire the flash?