Originally posted by Dtabbler It really blows my mind that these cameras and/or lenses do not simply have a setting to switch to screw drive. Clearly the capability is there... why not make it native?
It really is not needed. Screw drive only cameras (e.g. K100D, *ist D) work fine with the your lens. Those that support motor-in-lens work fine too, assuming the motor is working. I don't understand the frustration and push-back. If you purchased the inoperable lens with the assumption that parts would be readily available for a cheap fix, that was an unfortunate choice. Very few (no?) camera companies sell parts direct to consumers anymore and very few authorized repair shops sell parts as a pass-through. Sometimes U.S. Camera has Pentax parts, but not for your lens; I just checked. KEH may be able to repair your lens, but their pricing is flat rate and would be similar to Precision. The story is similar for Advance Camera in Portland.
If it were me, motor replacement would never have been on the table, knowing that the screwdrive conversion is so highly regarded by owners on this site. I have never read a complaint from anyone that has done it, just gratitude that someone figured out how it might be done. It is a very clever hack, IMHO.
Good luck. I hope you are able to get a satisfactory working lens without a lot of additional expense.
Edit: In regards to simply making screwdrive switchable, the capability actually is not there, natively. The "fix" involves rewriting the EPROM in the lens using a screw-drive-only body running in debug mode to do the write.
Steve