Fan only works on highest setting
 

Was driving my son's escape the other day and noticed the fan only blows when the setting is on 4. No other setting produces airflow at all.

Any suggestions as to why this would occur?

Hi fan speed is usually controlled by a separate relay because of the hi current required.
All other speeds usually go through a resistor that is generally mounted near the fan motor usually held by 2 small screws, easy to replace.
Most auto supply stores have those ,Blower Motor Resistors and not expensive..

Thanks so much, hanky. That makes sense.

Hanky, you hit the bullseye. Replaced the resistor yesterday--took all of 15 minutes. Now my son has his fan back for a long trip in a couple weeks.