Sounds like you have a blower motor resistor that has gone bad. Basically the fan 4, or high postion bypasses the resistors, and gets full power. In position 3, current goes thru 1 resistor, and in 2 it goes thru 2, and in 1 it goes thru all three. This slows the speed of the fan. A break in the second resistor will kill power in the 1 and 2 speed postions, but allow 3 and 4 to still be powered. Replace the resistor pack and it will be fixed.
This resistor is located on the right side of the airconditioning ducting under your dash. It is below the blower itself mounted right beside the recirculation control motor. If you remove your glove box, you might have a straight shot at replacing it. Remember when you tighten the screws, that this part is made of plastic, and do not over torque the screws. You can damage the new part and still have problems. They mount the resistor pack in the ducting to keep the heat down while power is going thru them at different speeds.
Good luck, and this should be an easy fix for you to do.
Saturday, July 29th, 2006 AT 4:28 PM