Hello all.
Although this item has become cold, I would like to add my two cents, since I was facing the same issue and I couldn't find much usefull information apart from "get a new camera body since repair is too expensive".
I experienced the same problem while on a trip; suddenly the camera freezes black when taking pictures, restarting 3 seconds later. The camera did not suffer any aparent stress before. Changed the lense, took the battery out , shook it a while, gentle taps in the bottom of the camera, and the problem dissapeared but only for another 4 pictures.
I let it rest for some weeks afterwards but the problem seemed not to subdue, so I started looking around internet and could find that it happened to several other people with several PL5, PL6 or PL7 but none was the wisest.
As posted above, videos work fine, since the camera doesn't need to operate the shutter (it is open, obviously, to see what you are pointing to)
After some months I finally had some time on my hands and decided, since warranty was long gone, to open it up and check it, black friday is near anyway should I eventually destroy it.
What I found was, that suddenly, with the back cover opened, the camera started working fine. Took several pictures, even bursts, and the camera was behaving properly. I put everything back, and once I was done, I managed to take a single picture before it stopped working again.
What I found is that there is a flex cable that operates the shutter that is folded in a 90º angle. When I put some pressure at that point, it works; if I fiddle with it, it doesn't, so I am guessing that the cable, the bent or some connections are not working.
I found a replacement in aliexpress (non original) for 10€; I am waiting for it, and I will let you know if I have any luck, but I am quite hopeful.