Similar to the method(s) for entering the debug mode of most later Pentax DSLRs, here is the latest disclosure, for the K-x:-
http://forums.dpreview.com/forums/read.asp?forum=1036&message=33494665
Quoted:-
But there is just one interesting and valuable thing Pentax has officially warned us in the above thread, that is, before you are to send your cam under warranty back to servicing, do remember to deactivate the debug mode!
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UPDATED: New Method to Access the Debug Mode of Various Pentax DSLRs
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