Curious situation. My 89 Cherokee blower motor stopped working when I start the vehicle.It does not work if if just turn the key to the on postition or if it is running. BUT, if I tap the motor itself it will work. If I tap the resistor it will work. Has anyone gone through this before? Thank you.

 

check the plug itself going into the blower! It may have melted a bit and is working when it wants to. It is caused by dust and dirt buiding up on the blower motor and drawing more power thus creating more heat and melting the plug!! been there done that fix!

 

Sounds like wiring or the motor its self, if the resistor is gone the fan will work but probley only on high speed! But where your knocking on stuff & its working probley a bad wire. Get a haynes manual & it will show u a wiring diagram & where they run too then start testing.

 

Hi, All the fan settings work when the blower works. I am assuming the resistor is ok and perhaps for some reason it is the motor is sticking?

 

Could be, when I had mine out I couldn't even trun the shaft!