2000 Dodge Stratus Q&A
2000 Dodge Stratus Question: Suddenly my heater fan only works on high speed. What could be the problem?
Sounds like the fan speed relay is giving you the problem. This is the part that contols the speeds of the blower motor by changing the resistance or the power going to the motor. It could also be the speed control switch on the control head but the resistor is the most common problem. - torque wrench
maybe your blower motor resistor is not good - Tomiko