Originally posted by Mikhail_Kriviniouk After dying the same death my k5 came back to life after being put into the sensor cleaning mode (the mirror did not go up itself) and lifting the mirror manually about half way then switching the camera off. It worked after this. further info - I seem to have established that if the voltage on the battery's terminals is below 8.1V the multiple mirror slap cannot be repeated... if you exchange the battery for a freshly charged one (8.4V), then It might do it. This is regardless of where the battery is and which one is used - body or grip. If there is a battery in the system with voltage higher than whatever - problems will be there. Under 8.1V and the weird behaviour can't be repeated.
Update: mine died again yesterday. nothing I tried makes the mirror go up or the shutter to open (release/ fire); everything else functions, inc. AF, viewing, editing etc, but the camera would not take a shot.