01 pon grand am gt your ac heater only works when it is on 5 and will shut off when you turn it off when on 1-4 it will not run at all the resistor has been replaced twice what else could it be?

switch, blower, wiring between.Could be that the resistor is not locked into place all the way after you put it in....you really have to cram the aftermarket ones into place and make sure they are snapped in. (have fun getting back at it...they are in the worst place ever)if it only works on 5, it is definitly the resistor. So, put a third one in. Theres probly a water leak into the heater box that's getting onto the resistor, shorting it out