blower motor resistor keeps failing

[tkr1985]

Would a bad blower motor (it still works--I'm wondering if it has some kind of fault) cause the blower motor resister to keep failing? I have replaced the resistor module twice and after a couple of days it stops again. Should I replace the blower motor itself? Would the blower motor relay have any impact? Should I replace that, too? I have the classic fan problems of only working on high speed and I've replaced the resistor twice..

Thanks!

 

[Megazuel]

The blower motor itself could be pulling too much amperage, causing the resistor to burn out. Put an amp meter inline on the power side going into the blower motor or go around the wire with a low amp clamp. Not sure what the ideal amp reading would be, but if its anywhere close to the fuse limit on high speed, its probably on its way out. Other than bad wiring (check your grounds!), the motor is the only other piece of the puzzle, or you could have gotten a bunch of bad resistors.... The relay shouldn't have anything to do with it, they are like switches, they either work or don't, and if you still have high speed blower when the lower speeds fail, you still have 12 volts going to the motor.