I have a 2001 Sebring Convertible and the fan switch does not work on 1 and 2, but does work on 3 and 4. I see from a previous post that if only setting 4 works the ballast resistor needs to be replaced. Could the ballast resistor be partially broken causing only 1 and 2 to not work?

Theoretically yes :)

On my 2001 4 door, the first time only the low speed burned out. The second time all three lower speeds burned out. Sounds like same old problem.

Regards:
Oldengineer