yup theres a resistor for different settings and thats why high works(12volt switched) and med/high, med/low, and low dont...cause the 12V is fed diretly to the motor without resistance, the others are set lower like, 7.2V and 5. and shit like that, which is how you get the diff speeds. i would buy or get a new blower motor resistor, if its a g body or gm full size the resistor pack is loacted next to the blower under the hood if im not mistaken, its sitting right on top of the fan housing on the pass side of the firewall. call napa they usually deal with these parts, and tell them what you have going on, if it isnt the resistor its got to be the switch that turns the fan speeds on the dash, or a bad connection else where. test lights are 4-6 bucks and save you headaches of testing shit all day. try those options, and report back...Originally posted by Joe5pt0@Aug 12 2005, 02:51 PM~3605103
I remember correctly, there is a resistor that limits current to the blower motor when in any position other then HIGH. So, when on HIGH the current does not travel through the resistor, rather a direct connection from switch to blower motor.
That being said, either your switch itself is bad (not allowing full connection) or you have some wiring issues from that point forward.