2004 chrysler sebring, the air won't blow when i turn on the a/c. it will only blow when i turn the knob all the way to the number 4 setting. help please!

blower resistor

blower motor resistor, had the same issue replaced blower motor resistor

Pls be more specific, doe's this fuse keep blowing or what? Fuse blows and your car won't start. I have a 2004 GTC and the #8 fuse kept blowing, had to replace the starter, (it was pulling 80amps instead or the normal 30-35) once the starter was replaced, no more starting issues and the fuse no longer blows. Hope this helps, good luck

A mechanic would check for voltage at the ac compressor and the freon charge when the ac stops working.
If the compressor is cutting on and off the idle speed will change.

I would expect this is more to do with a low coolant level than an electrical issue. If your coolant is low when you turn off the headlights your engine revs will increase slightly increasing the pressure in your coolant system and pushing fluid into your heater core.
Check your coolant reservior when your car is cold (first thing in the morning), it should be at max cold. If it is lower than this you may not have warm coolant in your heater core.
If this is the case...then where did your coolant go?
Most likely the thermostat/temp housing is leaking...replaced both on my two 2001 sebrings...common issue..~$150 for parts and a little awkward to install but fairly easy fix.

check theromstat, radiator has correct amount of coolant , water is flowing thru radiator. :heater core maybe bad

If the ac is turned on and it comes threw the defrost,then it is not the cooling fans,but check them to see that they are coming on,and they are turning fast,the control head is more likely the problem.

Cooling fans working? If you notice the air getting warm mostly while stopped, probaby cooling fans not turning on. if the fans are working properly, may be low on freon and need a recharge.

Ok Curtis... There may be a problem with the relay switch on this Sebring also check if the heater core is all the way open there should be a valve on the inline under the hood.

You need a new blower switch.