02 Suburban blower motor wont turn off

I have a 02 Suburban. For awhile settings 1 and 2 did not work and I lived with it fine. Yesterday the blower starting working on high all by itself and it couldn't be switched off. When I turned the car off it continued to blow. I removed the fuse under the hood to disable it. Now I neeed to put the fuse back whenever I need the fan. Is this an expensive deal to repair Is this an auto temp control system?

 

no, not an Automatic temp control. Basic heat/ac
Which fuse are you removing the 25amp or the 30amp?

 

If it was the 30 (underhood) that you pulled, put it back and try the 25 (under dash) and tell me what happens.

 

First, thank you for your assistance.
There are two fuses inside the truck. One is HVAC1-Climate Control System. 10A The second is HTR/A/C Climate Control Sysyem 30A. You mentioned the 30A so I assume the HTR/A/C fuse is it.

When I reinstalled the 25A under the hood the blower didn't come on and the selector switch did what is was supposed to do. I will not be able to test your thought process. However this has been the 3rd time this has happened to me. Once I returned to start it after a week of sitting to a dead battery and the battery is new. I am cautious about leaving the 25A fuse in while its parked. The truck is only used on weekends.

Can you tell me what you were thinking so when it happens again I will know which fuse to pull first.
It sounds like you have a bad blower motor resister. The relay is built into it and it sounds like the relay is energizing on it's own.
The resister is located in the blower housing, right next to the blower motor.

 

And the blower motor. Is it accessible because it's not under the hood. Do I need to remove the dashboard to get to it
Under the dash on the passenger side, easily accessible.

 

you have been a great help. I checked and the resistor is less than $50.. well worth changing it to not have this problem again. Thank you again
Your welcome. Be sure to post the results so others can see.

 

I removed the resistor as you thought, the electric board that goes inside the housing was melted, exposing the contacts inside. It was easily accessible and the new part was $30 so it was well worth it. Because it was burned through I'm hopeful that was the culprit. Thanks for the advice it saved a lot of money