98' Pontiac Bonneville SE. ... so I replaced the squirrel cage, blower motor resistor, and the switch for the various speeds. I'm very frustrated because I replaced what most people told me, nothing happens when I turn the manual knob from slow, medium, and high. ...the compressor works on the other knob if that helps.

just for info, jump 12 volts directly to blower motor. does it spin up. if yes, and if you have access to a volt meter, measure voltage at the connector to the blower motor. if you have voltage present, the connector may need cleaning or replacing.

if you do not have voltage present at the blower motor connector then you do have problems in the circuits. post results from the above checks and we can go from there with point to point testing.

Yeah, get yourself a cheap multimeter from Radio shack/favorite electronics dealer/walmart automotive dept. You don't need to necessarily have to be able to READ 12v on the scale, but if you have something that can tell you that you are getting power to the circuit, that's going to help a lot. A poor mans multimeter would be to tape wire to a 12v light bulb and ground one end and probe what you expect to be hot with the other. If it lights, you have power( Probably 12v ) If it lights dimly, then you might have 5v, which GM uses in a lot of its circuitry for the various sensor voltages.

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