Truck Repair: blower motor fuse, resistor pack, fuse one

Question
Hi there Van-
 I have a '01 Ranger that the blower motor keeps blowing the fuse.(I had assumed)  I have replaced the blower motor already and it still does it. The local Ford dealer is no help unless I leave it with them.  They will not even tell me what else is in line on the circuit.  What else & where else should I look at?  

Thanking you in advance,
Sincerely
Ben

Answer
Hello Ben,
The other thing that is in the circuit is a resistor pack.
The way the blower motor works at different speeds is by using combination of resistors.
If one of the resistor wires burns open and gets against ground, it could blow the fuse.
One question I have there is if the fuse blows in Hi speed, or only in one of the lower speeds.
Hi speed bypasses the resistor pack for the most part, although feedback in the circuit could also send power to the short.

The other possibility is the wire itself, from the blower motor. See if it is rubbed thru and contacting ground.
You can unhook it from the blower motor, and use an ohm meter to see if the wire shows direct short. if it is shorted, it will show a short even with the fuse blown or out.

Van