Blower fan only works on the high position?

Hello,

Sounds like you have an issue with the blower motor resistor.
The resistor is what controls the fan speed. Many times, when the resistor fails, it will only blow in one speed, typically in the highest setting.

The blower motor resistor is located on the blower motor housing. To access it you will have to remove the glove box.

Here is a helpful article:

https://www.2carpros.com/articles/blower-fan-motor-works-on-high-speed-only

I have attached diagrams for your reference.

Please let me know if you have any questions.
Thank you.