I have a dodge caravan 2002 and the key won't turn. It has done this in the past and with a few taps with a rubber mallet, it would work. Now its not working at all! Do I need to replace the key lock cylinder or the ignition switch? I am a single mother of 2 and my ex husband stole and sold my new car, so I have had to make several repairs on my older van... by myself because its cheaper, so any help on what's the best best would be appreciated!