AC has level 1 for the fan and 2-5 for AC. Cooling system does not turn on until I turn the knob to Level 4. Problem just started.
AC Levels all not working on 2003 Chevrolet Malibu
You need to go to your local autoparts store and replace the blower resistor. It is something you could do and it only cost around $25. It's under the dash on the passenger side. Eventually 4 and 5 will go out too.