I had the same problem with my 2003. The blower control only worked on 1 and 5. Also, when this began happening, the headlights would not automatically turn on when dark. Checked the fuse block with a multi-tester and narrowed the problem to the ignition switch. I actually dismantled the switch - I found a tutorial online showing how to dismantle and reassemble it. Half the contacts were carboned-up. I cleaned the contacts with a small brass brush and Radio Shack contact cleaner. The ignition switch is really poorly designed. Instead of self-wiping rotary contacts there are approximately six sets of contacts (six separate switches) that are opened or closed depending on the position of the ignition key. As each set of contacts opens or closes, there must be some arcing that causes the contacts to carbon up.
