Faulty flashgun.  Failed to fix this one. Always bugs me when I don't manage to sort stuff. But we all have to admit defeat sometimes, and move on to other things.

The little white box shaped thing is a fuse, and it had blown. The '2A' being a big clue (to me - as in two Amps). The letter 'T' above the 2A tells me that it's a 'time delay' or 'anti-surge' type. The other symbols to the left of the T are an 'L' and a small 'F'. In this case they identify the manufacturing company, somewhat appropriately (if not the correct spelling)  - "Littelfuse".

The fuse could be identified, but various frazzled parts couldn't.