99 TA Air Conditioning issue

[stealthtransam]

I'm having an interesting issue with my A/C in my 99 TA. Blower Motor position 3 does not seam to work. 1,2, &4 all work. I'm thinking this is a control problem or wiring issue. Not quite sure which one. Anyone have any insight. An A/C wiring diagram? or where the blower fan speed is actually controlled?

[PeterPar]

Check the fan switch and the blower resistor. I've attached a schematic from the 99 service manual that may help.

[stealthtransam]

Thanks for the schematic PeterPar! Looking at the schematic I can't see it being the Blower resistor. Unless it's a loose or bad connection on the Lt Blue (72) wire on the D contact. Looks like it probably will be the switch but now that I have the schematic I can test the switch and a few other things! Thanks! Does anyone know where the blower resistors are located in the vehicle? That way I can check the Lt Blue (72) wire as well to make sure there isn't a break in the wire.

[PeterPar]

Does anyone know where the blower resistors are located in the vehicle?

The manual doesn't show the location. It is listed as in the HVAC Module, forward and left of temperature control cable attachment. The removal procedure attached may help with finding the location.

[pajeff02]

GM blower resistors go bad from time to time. That would be the first thing to look at imo, so you are probably on the right track.