My AC was working fine, then it just stopped blowing air. The system still cycles on, but no airflow when turning the fan on for AC or heat. I suspect the blower motor. Should I replace the blower motor resistor at the same time? Any other thoughts?

Year make and model of your vehicle? Does it use the old style freon or the new 134-A refrigerant? What steps have you taken to make sure there isn't a freon or refrigerant leak? Are there any codes?

You stated no visible signs of leaks.

Did you know that more times than not you can't see a refrigerant leak or freon leak with the naked eye?

It went from blasting cold air to absolutely no air output at all. Same thing if you turn it to heat - not air coming out.

Are you sure about system pressures?
Did you check pressures with a gauge set?
Any blown fuses, master fuses, or circuit breakers?
Maybe a bad blower motor?
Maybe a bad compressor?

sounds like a blower motor problem.

do you need help checking it out, diagrams, locations, ect...?

kirbymc,

Jump the blower motor to any constant 12 volt source and give it good solid ground. If it doesn't come on and continue to run, it's shot and needs to be replaced.

check for voltage at blower motor connector when the blower speed is set at each setting (hi. med. low). If power is there, blower motor is bad.