If your Heat/AC fan only works on high speed then the blower resistor is bad. I have a brand new one for sale. It should fit 2000-2006 Wranglers with the 4.0 L (unsure if it will work on the 2.5). Part number 973-025. I bought this as a spare for my '04 TJ but have since traded it for a JK. $10 and FREE shipping!