Chrysler Repair: key wont turn, plastic squeeze tube, powdered graphite

Question
why won't key turn?

Answer
Hi Betty,
It could either be the lock tumblers, or it could be the hole in the housing into which the lock cylinder is positioned is excessively "sticky". Either way, I would try some powdered graphite a form of grease that comes in a plastic squeeze tube with a fine applicator tip. Just "puff" some graphite in the key hole and also around the circular edge of the lock cylinder/housing interface crack to force some powder there as well. Once you get it to move, then you can remove the lock cylinder once you get the lock mechanism to the position where it is when the engine is running. Tell me the year, and model of the car and I can tell you how to remove the cylinder.
Roland