99 jimmy

The blower moter only operates on the 3rd speed .1rst,2nd and 4th no longer work.Ive looked at the fuses,cleaned wiring contact going into the blower.Any other ideas would be appreciated--thanks

Your Heater/AC has a resistor, actually a set of coils of resistance wire that limit the current through the blower motor. The blower control selects them to control the speed that the motor runs. My bet is that one or more of the resistors has burned open. Check your service manual (I like haynes, $20 and well worth it), find the resistor and check it out, everything should be visable. It could also be the blower control switch, who knows.
Check Rockauto.com the resistor sells for $9.18 there, but there's always shipping. They are good, there's have everything from Acuras to YUGOs by year, by system, by part and pictures to boot. Great if for nothing other than refference.
See ya
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