Hello everybody.
I have a 1990 S-10. When I use the air conditioner while in the medium setting, the switch and the wire leaving the switch becomes very hot. (this wire is blue in color, and runs from the blower motor switch to a blower resistor. But, if I use the HIGH setting, I no longer feel or smell heat.
I have a wiring diagram, and on that diagram, I see that on the HIGH setting, all current is from the battery straight thru an enerized relay to the blower motor, bypassing the resistors altogether. At the medium, or low settings, the relay is not enerigized and current must flow thru the blower resistors to get to the blower motor.
I think that there is something wrong with those blower resistors. I have had basic electronics. I checked all resistors OUT of the circuit and all of them read ZERO resistance. It looks like just a coil of naked wire. It seems that under DC current ( which is what you have flowing to the motor) you will not have any DC resistance thru a coiled wire.
I thought there may be a problem with the relay, but I have replaced that but still have the problem. also, I have replaced the blue wire without success.
Can anybody tell me what the problem is ? I am very frustrated ! !!