Originally posted by gp1806 I don't own a K20D, so I tested my trusty old mule, a * ist DL. Tested with a Fluke 110 digital multimeter, I get 'infinity' resistance between the center point of the hot shoe and the base with the camera both on and off. The other contacts get different readings but still in the K-ohm range. If you are getting just a few ohms, I think something is wrong with the K20D. I don't know what Pentax means by 'recession'. If you think it might be wiring, see my album called K200D Repair. It's not a K20D but it should be similar.
Thanks!
very low resistance between central contact and the chassis means that they are connected in some way (shortened). And this is not normal - K10 shows infinite resistance.
Your album shows the white block with contacts, maybe it's the piece that must be replaced.