Hi there, and welcome.

The resistor and motor are synergistic. The resistor does not die on its own, but because the motor is drawing too much current and producing too little air flow to cool the resistor. Your resistor (or switch) may not even be dead, but the motor requires more current than the resistor will allow on those lower speeds, because the motor is binding, or otherwise damaged.

You could tell which is which by measuring the current at fuse #3, but this is tricky with commonly available multimeters, so best left to someone experienced and properly equipped. On the other hand, if you remove the fuse, set the motor to run on speed 1 or 2, you could probably see a small spark when connecting the fuse (be careful, it may get hot in a jiffy), indicating the circuit is drawing current, and that will tell you the resistor is still intact, but the motor can't get started on what current passes. Of course, if left this way, the resistor will eventually burn up. Synergy.

Either way, the resistor replacement requires the same labor as replacing the fan motor. I have not replaced a resistor or switch, just the fan motor. heater fan replacement It is a bit simpler in the 93 than it was in my 84 because you don't need to modify the mounting.


--
Art Benstein near Baltimore

V Day: A good wife always forgives her husband when she's wrong. -Rodney Dangerfield