I have a 97 850 T5 wagon that when I bought the car the blower motor didnt work. I found that fuse #5 - 30amp was not plugged in, so I plugged it in without the keys in the ignition and found the blower fan ran on high speed. So I left the fuse in with blower motor running and put in the keys to the ignition and figured out this made no difference. So I removed the fuse and I started researching the forums and came to the conclusion that the Blower Motor Resistor maybe bad. So I removed the resistor, ordered a new resistor and installed that resistor. Installed the #5 30 amp fuse and the motor didn't run so I thought great. Next proceeded to turn on the car and test the Climate controls and was able to control the speed of the fan. I thought awesome were back in business but now I am back to no blower fan at all....Is it possible the new blower motor resistor has failed already? or Is there another problem that I should be checking out such as the blower motor failed? Any help or suggestions would be helpful. Thanks

 

It is possible the new resistor went out but I think it's more likely the blower motor is at fault. I'd use a test light to see if it's getting power. If you find power on the red wire leading to the motor I'd make a jumper with a fuse in it so I could run power from the battery to the motor to see if it will spin. You can do it in place or pull it and do it out of the car. Just hang on to it as it will jerk if it does start to spin. Try to spin it by hand too so you know it's spinning freely on it's bearings. If it doesn't spin or spins hard the motors done. With age they do tend to bind up in the bearings. Some people have removed them and lubed up the bearings and run them some more but I replaced mine when the bearing started to screech a bit.
If the motor is binding up that added resistance does cause more current (amps) to flow through the blower motor resistor. If it's binding enough or long enough it can cause that resistor to overheat and fail. So if it's not working don't leave the system "ON" to see if the blower will start turning at some point as it might be building up heat in the resistor even though the motor isn't spinning and it could cause your new resistor to fail.