2005 Altima Heating fan problem

[ras_oscar]

Driving home this afternoon with the defrost fan set to medium. For no apparent reason, the fan incfreased speed to near full. Now the fan remains near full speed even when set to the off position. Problem occurs whether the selector is set to heat, or cooling, and whether the diverterr is set to windshield, vent or floor. From full to 5 detents below full the speed adjusts correctly, but below 5 the speed remains high.

[MaximA32]

That sounds like your blower motor resistor has taken a dump. It's a pretty common issue for pretty much all vehicles and the symptoms present themselves exactly as you described. It's fairly easy and shouldn't be too expensive.

[ras_oscar]

Yup, thats got it. Lesson learned, go aftermarket. The OEM part was twice the price.