Blower motor runs on high while the car is running.
While the car is running, the blower motor runs on high. The high/low control nob does not change the speed of blower. It will not turn off. It will fluctuate between vents when pressing the off button and the automatic button (A/C vents, floor vents, defrost vents).
It depends on weather you have ATC (Automatic Tempature Control) or not if you do I think your climate control unit needs to be rebuilt (100.00 for rebuilt 600.00 for NEW) one. They are noted for going bad especially in that year I think it's from 2000 on up that had the problem ones. Oh they even made it more difficult because the older ones (which work better) aren't interchangeable with newer ones. There are all kinds of companies on E-Bay that rebuild them check them out.
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