Originally posted by amg2000 Thanks for the clear instructions! I bought a new K70 in November 2017 and have been seeing signs of the aperture problem. So far it only seems to happen when the camera has bee turned off, the first exposure after I turn on the camera is either way underexposed if I'm using the optical viewfinder, or way overexposed if I'm using live view. After the first exposure it seems to be fine. I'm going to wait until the problem gets worse before I attempt this. I own both a K-10 with a damaged sensor, I can get the white solenoid from there.
Of course I bought this camera because I owned a K50 and wanted a backup (actually the K50 became the backup, and so far doesn't seem to have the aperture problem.) Kind of ironic that I was worried about my K50 getting the problem, and the K70 ends up with the problem.
Check via this method, and do it right away after your K-70 wasn't in use for a few days, because it is typical for the problem arising after a period when the camera was not used:
How to detect aperture-block failure/stuck solenoid on Pentax K-70 - PentaxForums.com
Do first the check via Live-View because it is very obvious to see the fully closed aperture instead of f4,0!
But don't release, switch LV off and then via OVF (opt. view-finder) take a photo in AV or TAV full open such as f1,8 with the DA50
My experience with the K30/50/500/K-S1/S2 is, that LV does work for a while and gives alright exposures (but not perfect!)
while you are the 4.th person I know of having overexposed photos with the K70 in LV-mode with stuck solenoid.
Now, also take into account:
The longer one runs a car with a fault in the engine, the higher the risk of further damage.
It isn't that dramatic with those Pentax bodies and stuck solenoid but it did happen.
Also you might be frustrated if the problem occurs just then when you have a good photo-session.
So you have the solenoid almost ready, now we have days of curfew, so a good time to meet that challenge?