Here we go again . #2 son scored a 91 buick road master s/w & gave it 2 me . The engine is chevy 305 thats seen better days but thats not the main problem.The s/w has auto heating climate control .The damn thing works (fan motor runs) with the key on &motor not running , u start the car and speed up the fan & nothing happens .After the engine has warmed up u can feel warm air at the vent but cant speed up blower.This sounds like a sensor some place , any ideas? the only thing i dont like about this s/d is that auto climate control, are they relieable ? or are they junk? thanks bunchs later bake.
Your problem is most likely the control module or the blower motor resistor. I would suggest that you get a GM chassis manual for your car, I have one for my Electra and it has been very helpful. I bought my manual from a couple of guys here in B.C. that have a part time business selling used manuals. If you are interested I can probably dig up the phone number, PM me if you want it. Greg