Your blower motor is getting ready to fail, it is usually gradual. I have replaced 2 on my 200 Kia Sportage and in both cases the low sppeds failed first. This may also require the relay be replaced as when it finally fails it can take the relay out.
blower motor resistor is burned out
Bad blower resistor. I just replaced mine.
Heater blower resistor is what controls the low medium high speeds...
The most common cause of the heater blower being on high only is the blower resister failing. The second most common problem is the blower switch going bad.
The blower motor speed resistor is burned out.
the heater resistor needs to be replaced it is mounted in the heater box next to the blower motor
Under the hood, on the firewall, passenger side, close to the blower motor. If the blower motor resistor is burned out, you should still have the high speed function.
A bad heater blower motor resistor would effect one or more blower speeds other than high.
Probably the blower motor resistor is shot.
try replaceing the switch that controls the low to high for heater It's gonna be the blower motor resistor (near the blower motor).
from what i have read it is the blower motor resistor it goes bad and only lets the fan run on high google blower motor resistor and read on
The blower motor speed resistor is burned out.