The blower motor is the fan that pushes conditioned air through your vents. When it goes, both your A/C and your heat go with it. It rarely fails without warning.
- Airflow that only works on the highest fan setting, a classic failing resistor or motor.
- A whine, squeal, or rumble from the dash that rises with fan speed.
- Weak airflow at every setting while the compressor still cycles normally.
- A burning-dust smell shortly after switching the fan on.
- Fan output that cuts in and out over bumps, pointing at wiring or the connector.
Caught early, this is a same-visit repair in your own driveway. Left alone through a Texas summer, it usually takes the resistor and sometimes the wiring harness with it.