I am posting this out of my experience that I had today, In hopes this might save someone a very costly repair at a shop or dealer. PROBLEM: Blower motor for AC/HEAT only works on setting number 5 (highest) Research: I did some research and found basically either the blower motor is bad, OR the resistor goes bad. REMOVAL: Disconect negative battery cable first. So I took the passenger side knee bolster off, and removed a few other plastic pieces under the dash which were held in by 7mm screws. Now I layed on my back on the floor and looked with a flashlight up under the dash, there is a large 5 wire harness going up into the bottom of the heater core. It is held in by two 5.5mm screws, the front one is easy but the back one requires finesse! 1/4" drive ratchet w/24" extension hooked to a swivel adapter into a 5.5mm socket. Basically guide the setup against the firewall, and it will basically line itself up with the screw. Remove this screw, and pull the resistor straight down. Unplug the large connector off of the resistor, and remove resistor from under dash. Design Flaw: Basically it is a circuit board, with copper metal contacts that in my case were all green and corroded. The board itself was burnt and obviously scored, but just to make sure it was the board I checked one more thing. With the car on and the connector in hand I used my testlight to find the hot wire, and then one by one I checked each of the other terminals to make sure when I turned the knob on the dash it was sending a signal to the resistor. The switch checked out 100%, so I was sure the resistor was bad. New Design: Autozone sold me a new one, which happened to be an updated design, larger circuit board for better cooling and beads of silicone where there never was before. Also the prongs which were metal are now silicone, looks like GM finally adressed this issue. $18.99 later I was back in business. Solution: For $18.99 and 2 hours of my time I fixed my blower problem, now all speeds 1-5 work perfectly. Always make sure you use dialectric grease when plugging this back in, good heat dissapation qualities. I just hope this can help somebody who might not think that they can do it, but really it wasn't that bad for my first time doing this. I should also mention that this car had the manual control panel, and not the fancy electronic climate control as I have never messed with one of those!!