+ I definitely agree with the answer from rj713 and just want to add to it. Remember though that bad resistors can be caused by blower motors with a lot of mileage on them.They build up higher resistance and that extra draw can destroy resistor. replacing the resistor may solve the problem for the short time but may re-occur. If that should happen, you may need a new blower motor. To get to the resistor, open your glove box, squeeze in both sides and let it drop down. You should now see the resistor directly behind there. It is about 3" x 1.5" with a 5/16 screw on each end and two wiring connectors. (one big one small). There is also a thermal fuse that I would replace as well since you are already there and the price for it is minor. It is a thermal fuse that goes bad often. you can fairly easy replace that one with a thermal fuse from Radio Shack or DigiKey has it as well on http://parts.digikey.com/1/parts/726775-thermal-fuse-144c-10a-axial-sdf-df144s.html. So you could replace that as well, but it needs to be soldered. for your resistor repair, there is a [http://www.youtube.com/watch?v=AS2mVNV2NFk|Video] that will help you with it. the part is readily available at places [http://autoshepherd.com/product/Standard-HVAC-Blower-Motor-Resistor/4074/STD/RU-362?sku=STD:RU-362&utm_source=google%20product%20search&utm_medium=cse&utm_campaign=HVAC%20Blower%20Motor%20Resistor|like this] Hope this helps, and I did not mean to bump rj713's answer, but can not attach images to comments. So, my apologies.
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