The blower on my 2001 Cherokee stopped working. I Have traced the circuit s and found voltage at the relay and changed the relay .Then I checked the resistor pack and it had continuity (a bit of rust but it still resists). The connector at the back of the switch looked fine. Does any body know how to bypass the switch and feed power directly to the blower so it can be ruled in or out? And if the blower motor is fried does any one know how to change the blower without draining the a.c. system. I read that a poser named leebow claims to have done that,but he/she must have been abducted by L.G.M. to show how it is done. By the way yanks to cgrossi for the reply to coil rail issue.

 

You said relay. Did you also change out the ballast resistor? It should be located on the cabin side of the lower part of the HVAC ductwork in the passenger footwell. If it fries, the fan may only work on certain speeds or not at all. I just changed the one in my 97. It had melted the wires as well when it went.

 

Does the blower work on high? if it does then it's your rheostat which under your dash pass side, if it fails your blower works in the high setting only.

 

I did manage to pull the resistor and check it with a ohm meter. It had rust on the surface of the heat sink /safety cage,but otherwise passed the test described in the service manual. And no Davida the blower doesn,t work at all. And 2 evil 4U the wires were not melted. but thanks for replying . So what I would like to try is to apply battery power directly to the blower motor so as to rule it in or out as the problem . The challenge is figuring out how to do this from inside the cabin as there is no easy access to the wires from the engine compartment.