Is this typical sign on most or all cars?? I have that happen on my vw and it was the resistor and my moms trailblazer is doing the same thing. Thought it might be the resistor but I wasnt sure since I never worked on a chevy.
Nothing says "were dating" like sticking your dick in her.
the resistor limits the voltage that travels through the circuit for different fan setting so when it goes bad it wont limit the voltage at all thus only working on high.... i think lol
Kind of how it works. There are 4 settings on the blower knob and I'll call them 1, 2, 3, and 4 (1 being "low" and 4 being "high"). When the knob is set on 4, there is no resistor in the circuit and the blower motor receives 12V. When the knob is set on 3, there's 1 resistor in the circuit and the blower motor receives 10V (made up voltage). Since it's only 10V, the blower will run slower than if it received 12V. When the knob is on 2, there's 2 resistor in the circuit and the blower motor receives 8V (made up voltage). With the knob on 1 there are 3 resistors in the circuit and the motor receives even less voltage.
When the blower motor resistors burn out, they act as open circuits. Open circuits provide the blower motor with 0V. Since knob setting 4 is just a jumper across the resistor pack, there's no resistor to burn out. Sometimes you'll burn out 1 or 2 resistors and it'll only work on setting 3 and 4.