Blower motor only works on HIGH?

[dsfii93sport]

Hi,, My blower motor will only work on the high setting and that is it. And if I push the knob to turn on the AC - the blower shuts off. Any ideas what could be bad? Blower Resistors?

Where are the Blower Resistors located?

Its in a 93 Explorer

 

[Billy177]

you sounds like the resistors

 

[Crankcase]

The resistor s located in the engine bay.....there will be wires running into the blower motor. At the end of them, there is a device held on by two bolts on the passenger side...that is it.

 

[TSTONE]

blower motor resitor

 

[Opera House]

In this resistor assembly, there is a thermal fuse that protects it from overheating and melting things. It only is in the circuit at speeds belw high. Because this is a chemical fuse they can sometimes go bad just from age. It can also open up if the vents get blocked (one student used the vents as a cloths dryer on the trip back to college) or the motor starts to drag and draws higher current. Not enough current to blow the heater fuse but enough for the resistors to overheat. If the motor is drawing too much a new resistor assembly will go bad too. Just the thermal fuse (looks like a metal diode) can be crimped in with a $2 Radio Shack part or you can just jumper it out (hey, it's a 93) and have no protection.

 

[dsfii93sport]

Well,, I now have a new blower motor, and new resistors and it still doesnt work! Only on HIGH.. Well i jiggled w/ the switch controls and got it to come on the middle setting. So now all that works is Mid setting w/ AC on. Then HIGH setting w/ AC off! haha...

Do you think this switch could be shot?

 

[Opera House]

All the switch settings connect the ran motor and the resistors to ground. Since you still have the high speed setting, the ground connection to the switch seems good. That leaves the swich being bad.

 

[Pheonixx77]

if it works intermittently your culproit is the relay in the power box under the hood. i fought this for 2 years before i figured it out. the relay is 10$ at autozone.